* [PATCH v3 01/35] qom: replace 'can_be_deleted' with 'prepare_delete'
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 02/35] monitor: replace 'common' with 'parent_obj' in MonitorHMP Daniel P. Berrangé
` (33 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
While most objects can perform all their cleanup in the finalizer
method, there can be interactions with other resources / subsystems
/ threads which require that some cleanup be performed on an user
creatable object before unparenting it and entering finalization.
The current 'can_be_deleted' method runs in the deletion path and
is intended to be used to block deletion. While it could be used
to perform cleanup tasks, its name suggests it should be free of
side-effects.
Generalize this by renaming it to 'prepare_delete', explicitly
allowing for cleanup to be provided. Existing users of 'can_be_deleted'
are re-written, which provides them with more detailed/tailored error
messages.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
backends/cryptodev.c | 10 +++++++---
backends/hostmem.c | 5 +++--
backends/iommufd.c | 10 +++++++---
block/throttle-groups.c | 10 +++++++---
event-loop-base.c | 8 ++++----
include/qom/object_interfaces.h | 26 +++++++++++++++++---------
include/system/event-loop-base.h | 2 +-
net/can/can_core.c | 5 +++--
qom/object_interfaces.c | 14 ++++++--------
tests/qemu-iotests/245 | 4 ++--
util/main-loop.c | 5 +++--
11 files changed, 60 insertions(+), 39 deletions(-)
diff --git a/backends/cryptodev.c b/backends/cryptodev.c
index 79f8882d3b..90110dc633 100644
--- a/backends/cryptodev.c
+++ b/backends/cryptodev.c
@@ -454,9 +454,13 @@ bool cryptodev_backend_is_ready(CryptoDevBackend *backend)
}
static bool
-cryptodev_backend_can_be_deleted(UserCreatable *uc)
+cryptodev_backend_prepare_delete(UserCreatable *uc, Error **errp)
{
- return !cryptodev_backend_is_used(CRYPTODEV_BACKEND(uc));
+ if (cryptodev_backend_is_used(CRYPTODEV_BACKEND(uc))) {
+ error_setg(errp, "Cryptodev backend is still in use");
+ return false;
+ }
+ return true;
}
static void cryptodev_backend_instance_init(Object *obj)
@@ -613,7 +617,7 @@ cryptodev_backend_class_init(ObjectClass *oc, const void *data)
UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
ucc->complete = cryptodev_backend_complete;
- ucc->can_be_deleted = cryptodev_backend_can_be_deleted;
+ ucc->prepare_delete = cryptodev_backend_prepare_delete;
QTAILQ_INIT(&crypto_clients);
object_class_property_add(oc, "queues", "uint32",
diff --git a/backends/hostmem.c b/backends/hostmem.c
index cd2085fb3c..eb915c64bc 100644
--- a/backends/hostmem.c
+++ b/backends/hostmem.c
@@ -434,9 +434,10 @@ host_memory_backend_memory_complete(UserCreatable *uc, Error **errp)
}
static bool
-host_memory_backend_can_be_deleted(UserCreatable *uc)
+host_memory_backend_prepare_delete(UserCreatable *uc, Error **errp)
{
if (host_memory_backend_is_mapped(MEMORY_BACKEND(uc))) {
+ error_setg(errp, "Host memory backend is still mapped");
return false;
} else {
return true;
@@ -508,7 +509,7 @@ host_memory_backend_class_init(ObjectClass *oc, const void *data)
UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
ucc->complete = host_memory_backend_memory_complete;
- ucc->can_be_deleted = host_memory_backend_can_be_deleted;
+ ucc->prepare_delete = host_memory_backend_prepare_delete;
object_class_property_add_bool(oc, "merge",
host_memory_backend_get_merge,
diff --git a/backends/iommufd.c b/backends/iommufd.c
index 09624cd652..7af49f6de3 100644
--- a/backends/iommufd.c
+++ b/backends/iommufd.c
@@ -63,11 +63,15 @@ static void iommufd_backend_set_fd(Object *obj, const char *str, Error **errp)
trace_iommu_backend_set_fd(be->fd);
}
-static bool iommufd_backend_can_be_deleted(UserCreatable *uc)
+static bool iommufd_backend_prepare_delete(UserCreatable *uc, Error **errp)
{
IOMMUFDBackend *be = IOMMUFD_BACKEND(uc);
- return !be->users;
+ if (be->users) {
+ error_setg(errp, "IOMMUFD backend still has %d users", be->users);
+ return false;
+ }
+ return true;
}
static void iommufd_backend_complete(UserCreatable *uc, Error **errp)
@@ -92,7 +96,7 @@ static void iommufd_backend_class_init(ObjectClass *oc, const void *data)
{
UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
- ucc->can_be_deleted = iommufd_backend_can_be_deleted;
+ ucc->prepare_delete = iommufd_backend_prepare_delete;
ucc->complete = iommufd_backend_complete;
object_class_property_add_str(oc, "fd", NULL, iommufd_backend_set_fd);
diff --git a/block/throttle-groups.c b/block/throttle-groups.c
index 4b1b1944c2..7836fc4c76 100644
--- a/block/throttle-groups.c
+++ b/block/throttle-groups.c
@@ -960,9 +960,13 @@ static void throttle_group_get_limits(Object *obj, Visitor *v,
visit_type_ThrottleLimits(v, name, &argp, errp);
}
-static bool throttle_group_can_be_deleted(UserCreatable *uc)
+static bool throttle_group_prepare_delete(UserCreatable *uc, Error **errp)
{
- return OBJECT(uc)->ref == 1;
+ if (OBJECT(uc)->ref > 1) {
+ error_setg(errp, "Throttle group still has multiple references");
+ return false;
+ }
+ return true;
}
static void throttle_group_obj_class_init(ObjectClass *klass,
@@ -972,7 +976,7 @@ static void throttle_group_obj_class_init(ObjectClass *klass,
UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
ucc->complete = throttle_group_obj_complete;
- ucc->can_be_deleted = throttle_group_can_be_deleted;
+ ucc->prepare_delete = throttle_group_prepare_delete;
/* individual properties */
for (i = 0; i < sizeof(properties) / sizeof(ThrottleParamInfo); i++) {
diff --git a/event-loop-base.c b/event-loop-base.c
index 8ca143bea4..ee5987ddbf 100644
--- a/event-loop-base.c
+++ b/event-loop-base.c
@@ -85,13 +85,13 @@ static void event_loop_base_complete(UserCreatable *uc, Error **errp)
}
}
-static bool event_loop_base_can_be_deleted(UserCreatable *uc)
+static bool event_loop_base_prepare_delete(UserCreatable *uc, Error **errp)
{
EventLoopBaseClass *bc = EVENT_LOOP_BASE_GET_CLASS(uc);
EventLoopBase *backend = EVENT_LOOP_BASE(uc);
- if (bc->can_be_deleted) {
- return bc->can_be_deleted(backend);
+ if (bc->prepare_delete) {
+ return bc->prepare_delete(backend, errp);
}
return true;
@@ -102,7 +102,7 @@ static void event_loop_base_class_init(ObjectClass *klass,
{
UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
ucc->complete = event_loop_base_complete;
- ucc->can_be_deleted = event_loop_base_can_be_deleted;
+ ucc->prepare_delete = event_loop_base_prepare_delete;
object_class_property_add(klass, "aio-max-batch", "int",
event_loop_base_get_param,
diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h
index e2b8615617..afd0fb93b2 100644
--- a/include/qom/object_interfaces.h
+++ b/include/qom/object_interfaces.h
@@ -20,8 +20,10 @@ typedef struct UserCreatable UserCreatable;
* UserCreatableClass:
* @parent_class: the base class
* @complete: callback to be called after @obj's properties are set.
- * @can_be_deleted: callback to be called before an object is removed
- * to check if @obj can be removed safely.
+ * @prepare_delete: to be called before an attempt to delete @obj
+ * to validate whether the object can be deleted and trigger any
+ * cleanup of any resources which have to be dealt with before the
+ * object is unparented and enters finalization.
*
* Interface is designed to work with -object/object-add/object_add
* commands.
@@ -36,7 +38,9 @@ typedef struct UserCreatable UserCreatable;
* For objects created without using -object/object-add/object_add,
* @user_creatable_complete() wrapper should be called manually if
* object's type implements USER_CREATABLE interface and needs
- * complete() callback to be called.
+ * complete() callback to be called. Similarly @user_creatable_prepare_delete()
+ * should be called manually prior to an attempt to the delete the
+ * object.
*/
struct UserCreatableClass {
/* <private> */
@@ -44,7 +48,7 @@ struct UserCreatableClass {
/* <public> */
void (*complete)(UserCreatable *uc, Error **errp);
- bool (*can_be_deleted)(UserCreatable *uc);
+ bool (*prepare_delete)(UserCreatable *uc, Error **errp);
};
/**
@@ -61,13 +65,17 @@ struct UserCreatableClass {
bool user_creatable_complete(UserCreatable *uc, Error **errp);
/**
- * user_creatable_can_be_deleted:
- * @uc: the object whose can_be_deleted() method is called if implemented
+ * user_creatable_prepare_delete:
+ * @uc: the user-creatable object whose prepare_delete() method is called
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Wrapper to call prepare_delete() class method if defined, otherwise
+ * does nothing.
*
- * Wrapper to call can_be_deleted() method if one of types it's inherited
- * from implements USER_CREATABLE interface.
+ * Returns: %true on success or if prepare_delete() is not defined,
+ * %false on failure.
*/
-bool user_creatable_can_be_deleted(UserCreatable *uc);
+bool user_creatable_prepare_delete(UserCreatable *uc, Error **errp);
/**
* user_creatable_add_qapi:
diff --git a/include/system/event-loop-base.h b/include/system/event-loop-base.h
index 130629e7f3..1e1e427ac7 100644
--- a/include/system/event-loop-base.h
+++ b/include/system/event-loop-base.h
@@ -24,7 +24,7 @@ struct EventLoopBaseClass {
void (*init)(EventLoopBase *base, Error **errp);
void (*update_params)(EventLoopBase *base, Error **errp);
- bool (*can_be_deleted)(EventLoopBase *base);
+ bool (*prepare_delete)(EventLoopBase *base, Error **errp);
};
struct EventLoopBase {
diff --git a/net/can/can_core.c b/net/can/can_core.c
index 77fe2b8ba4..8df9375167 100644
--- a/net/can/can_core.c
+++ b/net/can/can_core.c
@@ -143,8 +143,9 @@ int can_bus_client_set_filters(CanBusClientState *client,
}
-static bool can_bus_can_be_deleted(UserCreatable *uc)
+static bool can_bus_prepare_delete(UserCreatable *uc, Error **errp)
{
+ error_setg(errp, "Deleting can bus devices is not supported");
return false;
}
@@ -153,7 +154,7 @@ static void can_bus_class_init(ObjectClass *klass,
{
UserCreatableClass *uc_klass = USER_CREATABLE_CLASS(klass);
- uc_klass->can_be_deleted = can_bus_can_be_deleted;
+ uc_klass->prepare_delete = can_bus_prepare_delete;
}
static const TypeInfo can_bus_info = {
diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c
index 7080f85f95..6faa0b2fd9 100644
--- a/qom/object_interfaces.c
+++ b/qom/object_interfaces.c
@@ -32,16 +32,15 @@ bool user_creatable_complete(UserCreatable *uc, Error **errp)
return !*errp;
}
-bool user_creatable_can_be_deleted(UserCreatable *uc)
+bool user_creatable_prepare_delete(UserCreatable *uc, Error **errp)
{
-
UserCreatableClass *ucc = USER_CREATABLE_GET_CLASS(uc);
+ ERRP_GUARD();
- if (ucc->can_be_deleted) {
- return ucc->can_be_deleted(uc);
- } else {
- return true;
+ if (ucc->prepare_delete) {
+ ucc->prepare_delete(uc, errp);
}
+ return !*errp;
}
void user_creatable_add_qapi(ObjectOptions *options, Error **errp)
@@ -253,8 +252,7 @@ bool user_creatable_del(const char *id, Error **errp)
return false;
}
- if (!user_creatable_can_be_deleted(USER_CREATABLE(obj))) {
- error_setg(errp, "object '%s' is in use, can not be deleted", id);
+ if (!user_creatable_prepare_delete(USER_CREATABLE(obj), errp)) {
return false;
}
diff --git a/tests/qemu-iotests/245 b/tests/qemu-iotests/245
index f96610f510..e161bcfda9 100755
--- a/tests/qemu-iotests/245
+++ b/tests/qemu-iotests/245
@@ -801,7 +801,7 @@ class TestBlockdevReopen(iotests.QMPTestCase):
# Now group1 is in use, it cannot be deleted
result = self.vm.qmp('object-del', id = 'group1')
self.assert_qmp(result, 'error/class', 'GenericError')
- self.assert_qmp(result, 'error/desc', "object 'group1' is in use, can not be deleted")
+ self.assert_qmp(result, 'error/desc', "Throttle group still has multiple references")
# Default options, this switches the group back to group0
self.reopen(opts)
@@ -809,7 +809,7 @@ class TestBlockdevReopen(iotests.QMPTestCase):
# So now we cannot delete group0
result = self.vm.qmp('object-del', id = 'group0')
self.assert_qmp(result, 'error/class', 'GenericError')
- self.assert_qmp(result, 'error/desc', "object 'group0' is in use, can not be deleted")
+ self.assert_qmp(result, 'error/desc', "Throttle group still has multiple references")
# But group1 is free this time, and it can be deleted
self.vm.cmd('object-del', id = 'group1')
diff --git a/util/main-loop.c b/util/main-loop.c
index ad8645c30a..67ee06c311 100644
--- a/util/main-loop.c
+++ b/util/main-loop.c
@@ -218,8 +218,9 @@ static void main_loop_init(EventLoopBase *base, Error **errp)
mloop = m;
}
-static bool main_loop_can_be_deleted(EventLoopBase *base)
+static bool main_loop_prepare_delete(EventLoopBase *base, Error **errp)
{
+ error_setg(errp, "Deleting main loop is not supported");
return false;
}
@@ -229,7 +230,7 @@ static void main_loop_class_init(ObjectClass *oc, const void *class_data)
bc->init = main_loop_init;
bc->update_params = main_loop_update_params;
- bc->can_be_deleted = main_loop_can_be_deleted;
+ bc->prepare_delete = main_loop_prepare_delete;
}
static const TypeInfo main_loop_info = {
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 02/35] monitor: replace 'common' with 'parent_obj' in MonitorHMP
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 01/35] qom: replace 'can_be_deleted' with 'prepare_delete' Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 03/35] monitor: replace 'common' with 'parent_obj' in MonitorQMP Daniel P. Berrangé
` (32 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
The field name 'parent_obj' is standard practice for QOM structs
so align the HMP monitor.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dave@treblig.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/hmp-cmds.c | 2 +-
monitor/hmp.c | 43 ++++++++++++++++++++------------------
monitor/monitor-internal.h | 2 +-
monitor/monitor.c | 6 +++---
monitor/qmp-cmds.c | 10 ++++-----
ui/ui-hmp-cmds.c | 2 +-
6 files changed, 34 insertions(+), 31 deletions(-)
diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
index 443b8c785d..e139caeba9 100644
--- a/monitor/hmp-cmds.c
+++ b/monitor/hmp-cmds.c
@@ -287,7 +287,7 @@ void hmp_info_sync_profile(Monitor *mon, const QDict *qdict)
void hmp_info_history(Monitor *mon, const QDict *qdict)
{
- MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, common);
+ MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, parent_obj);
int i;
const char *str;
diff --git a/monitor/hmp.c b/monitor/hmp.c
index cc4390486e..3dde52ddbe 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -48,9 +48,9 @@ static void monitor_command_cb(void *opaque, const char *cmdline,
{
MonitorHMP *mon = opaque;
- monitor_suspend(&mon->common);
+ monitor_suspend(&mon->parent_obj);
handle_hmp_command(mon, cmdline);
- monitor_resume(&mon->common);
+ monitor_resume(&mon->parent_obj);
}
void monitor_read_command(MonitorHMP *mon, int show_prompt)
@@ -73,7 +73,7 @@ int monitor_read_password(MonitorHMP *mon, ReadLineFunc *readline_func,
/* prompt is printed on return from the command handler */
return 0;
} else {
- monitor_printf(&mon->common,
+ monitor_printf(&mon->parent_obj,
"terminal does not support password prompting\n");
return -ENOTTY;
}
@@ -695,7 +695,7 @@ static const HMPCommand *monitor_parse_command(MonitorHMP *hmp_mon,
const char **cmdp,
HMPCommand *table)
{
- Monitor *mon = &hmp_mon->common;
+ Monitor *mon = &hmp_mon->parent_obj;
const char *p;
const HMPCommand *cmd;
char cmdname[256];
@@ -1188,35 +1188,37 @@ void handle_hmp_command(MonitorHMP *mon, const char *cmdline)
if (!cmd->cmd && !cmd->cmd_info_hrt) {
/* FIXME: is it useful to try autoload modules here ??? */
- monitor_printf(&mon->common, "Command \"%.*s\" is not available.\n",
+ monitor_printf(&mon->parent_obj, "Command \"%.*s\" is not available.\n",
(int)(cmdline - cmd_start), cmd_start);
return;
}
- qdict = monitor_parse_arguments(&mon->common, &cmdline, cmd);
+ qdict = monitor_parse_arguments(&mon->parent_obj, &cmdline, cmd);
if (!qdict) {
while (cmdline > cmd_start && qemu_isspace(cmdline[-1])) {
cmdline--;
}
- monitor_printf(&mon->common, "Try \"help %.*s\" for more information\n",
+ monitor_printf(&mon->parent_obj,
+ "Try \"help %.*s\" for more information\n",
(int)(cmdline - cmd_start), cmd_start);
return;
}
if (!cmd->coroutine) {
/* old_mon is non-NULL when called from qmp_human_monitor_command() */
- Monitor *old_mon = monitor_set_cur(qemu_coroutine_self(), &mon->common);
- handle_hmp_command_exec(&mon->common, cmd, qdict);
+ Monitor *old_mon = monitor_set_cur(qemu_coroutine_self(),
+ &mon->parent_obj);
+ handle_hmp_command_exec(&mon->parent_obj, cmd, qdict);
monitor_set_cur(qemu_coroutine_self(), old_mon);
} else {
HandleHmpCommandCo data = {
- .mon = &mon->common,
+ .mon = &mon->parent_obj,
.cmd = cmd,
.qdict = qdict,
.done = false,
};
Coroutine *co = qemu_coroutine_create(handle_hmp_command_co, &data);
- monitor_set_cur(co, &mon->common);
+ monitor_set_cur(co, &mon->parent_obj);
aio_co_enter(qemu_get_aio_context(), co);
AIO_WAIT_WHILE_UNLOCKED(NULL, !data.done);
}
@@ -1434,7 +1436,7 @@ cleanup:
static void monitor_read(void *opaque, const uint8_t *buf, int size)
{
- MonitorHMP *mon = container_of(opaque, MonitorHMP, common);
+ MonitorHMP *mon = container_of(opaque, MonitorHMP, parent_obj);
int i;
if (mon->rs) {
@@ -1443,7 +1445,7 @@ static void monitor_read(void *opaque, const uint8_t *buf, int size)
}
} else {
if (size == 0 || buf[size - 1] != 0) {
- monitor_printf(&mon->common, "corrupted command\n");
+ monitor_printf(&mon->parent_obj, "corrupted command\n");
} else {
handle_hmp_command(mon, (char *)buf);
}
@@ -1512,26 +1514,26 @@ static void G_GNUC_PRINTF(2, 3) monitor_readline_printf(void *opaque,
MonitorHMP *mon = opaque;
va_list ap;
va_start(ap, fmt);
- monitor_vprintf(&mon->common, fmt, ap);
+ monitor_vprintf(&mon->parent_obj, fmt, ap);
va_end(ap);
}
static void monitor_readline_flush(void *opaque)
{
MonitorHMP *mon = opaque;
- monitor_flush(&mon->common);
+ monitor_flush(&mon->parent_obj);
}
void monitor_init_hmp(Chardev *chr, bool use_readline, Error **errp)
{
MonitorHMP *mon = g_new0(MonitorHMP, 1);
- if (!qemu_chr_fe_init(&mon->common.chr, chr, errp)) {
+ if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) {
g_free(mon);
return;
}
- monitor_data_init(&mon->common, false, false, false);
+ monitor_data_init(&mon->parent_obj, false, false, false);
mon->use_readline = use_readline;
if (mon->use_readline) {
@@ -1542,9 +1544,10 @@ void monitor_init_hmp(Chardev *chr, bool use_readline, Error **errp)
monitor_read_command(mon, 0);
}
- qemu_chr_fe_set_handlers(&mon->common.chr, monitor_can_read, monitor_read,
- monitor_event, NULL, &mon->common, NULL, true);
- monitor_list_append(&mon->common);
+ qemu_chr_fe_set_handlers(&mon->parent_obj.chr,
+ monitor_can_read, monitor_read, monitor_event,
+ NULL, &mon->parent_obj, NULL, true);
+ monitor_list_append(&mon->parent_obj);
}
/**
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index a5c4aba306..eb301ea796 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -128,7 +128,7 @@ struct Monitor {
};
struct MonitorHMP {
- Monitor common;
+ Monitor parent_obj;
bool use_readline;
/*
* State used only in the thread "owning" the monitor.
diff --git a/monitor/monitor.c b/monitor/monitor.c
index 00b93ed612..2a1b511ff4 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -132,7 +132,7 @@ static inline bool monitor_is_hmp_non_interactive(const Monitor *mon)
return false;
}
- return !monitor_uses_readline(container_of(mon, MonitorHMP, common));
+ return !monitor_uses_readline(container_of(mon, MonitorHMP, parent_obj));
}
static gboolean monitor_unblocked(void *do_not_use, GIOCondition cond,
@@ -542,7 +542,7 @@ static void monitor_accept_input(void *opaque)
qemu_mutex_lock(&mon->mon_lock);
if (!monitor_is_qmp(mon) && mon->reset_seen) {
- MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, common);
+ MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, parent_obj);
assert(hmp_mon->rs);
readline_restart(hmp_mon->rs);
qemu_mutex_unlock(&mon->mon_lock);
@@ -627,7 +627,7 @@ void monitor_data_destroy(Monitor *mon)
if (monitor_is_qmp(mon)) {
monitor_data_destroy_qmp(container_of(mon, MonitorQMP, common));
} else {
- readline_free(container_of(mon, MonitorHMP, common)->rs);
+ readline_free(container_of(mon, MonitorHMP, parent_obj)->rs);
}
g_string_free(mon->outbuf, true);
qemu_mutex_destroy(&mon->mon_lock);
diff --git a/monitor/qmp-cmds.c b/monitor/qmp-cmds.c
index 0c409c27dc..aa9ee8a391 100644
--- a/monitor/qmp-cmds.c
+++ b/monitor/qmp-cmds.c
@@ -168,10 +168,10 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
char *output = NULL;
MonitorHMP hmp = {};
- monitor_data_init(&hmp.common, false, true, false);
+ monitor_data_init(&hmp.parent_obj, false, true, false);
if (has_cpu_index) {
- int ret = monitor_set_cpu(&hmp.common, cpu_index);
+ int ret = monitor_set_cpu(&hmp.parent_obj, cpu_index);
if (ret < 0) {
error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cpu-index",
"a CPU number");
@@ -181,12 +181,12 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
handle_hmp_command(&hmp, command_line);
- WITH_QEMU_LOCK_GUARD(&hmp.common.mon_lock) {
- output = g_strdup(hmp.common.outbuf->str);
+ WITH_QEMU_LOCK_GUARD(&hmp.parent_obj.mon_lock) {
+ output = g_strdup(hmp.parent_obj.outbuf->str);
}
out:
- monitor_data_destroy(&hmp.common);
+ monitor_data_destroy(&hmp.parent_obj);
return output;
}
diff --git a/ui/ui-hmp-cmds.c b/ui/ui-hmp-cmds.c
index 1e9bc77bd8..bc48e757bb 100644
--- a/ui/ui-hmp-cmds.c
+++ b/ui/ui-hmp-cmds.c
@@ -342,7 +342,7 @@ void hmp_change_vnc(Monitor *mon, const char *device, const char *target,
return;
}
if (!arg) {
- MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, common);
+ MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, parent_obj);
monitor_read_password(hmp_mon, hmp_change_read_arg, NULL);
} else {
qmp_change_vnc_password(arg, errp);
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 03/35] monitor: replace 'common' with 'parent_obj' in MonitorQMP
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 01/35] qom: replace 'can_be_deleted' with 'prepare_delete' Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 02/35] monitor: replace 'common' with 'parent_obj' in MonitorHMP Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 04/35] monitor: rename monitor_init* to monitor_new* Daniel P. Berrangé
` (31 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
The field name 'parent_obj' is standard practice for QOM structs
so align the QMP monitor.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/monitor-internal.h | 2 +-
monitor/monitor.c | 4 ++--
monitor/qmp-cmds-control.c | 4 ++--
monitor/qmp.c | 40 +++++++++++++++++++-------------------
4 files changed, 25 insertions(+), 25 deletions(-)
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index eb301ea796..4da2b2a677 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -141,7 +141,7 @@ struct MonitorHMP {
};
typedef struct {
- Monitor common;
+ Monitor parent_obj;
JSONMessageParser parser;
bool pretty;
/*
diff --git a/monitor/monitor.c b/monitor/monitor.c
index 2a1b511ff4..0b7b464ebe 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -308,7 +308,7 @@ static void monitor_qapi_event_emit(QAPIEvent event, QDict *qdict)
continue;
}
- qmp_mon = container_of(mon, MonitorQMP, common);
+ qmp_mon = container_of(mon, MonitorQMP, parent_obj);
{
QEMU_LOCK_GUARD(&mon->mon_lock);
if (qmp_mon->commands == &qmp_cap_negotiation_commands) {
@@ -625,7 +625,7 @@ void monitor_data_destroy(Monitor *mon)
g_free(mon->mon_cpu_path);
qemu_chr_fe_deinit(&mon->chr, false);
if (monitor_is_qmp(mon)) {
- monitor_data_destroy_qmp(container_of(mon, MonitorQMP, common));
+ monitor_data_destroy_qmp(container_of(mon, MonitorQMP, parent_obj));
} else {
readline_free(container_of(mon, MonitorHMP, parent_obj)->rs);
}
diff --git a/monitor/qmp-cmds-control.c b/monitor/qmp-cmds-control.c
index 150ca9f5cb..af6a2a118b 100644
--- a/monitor/qmp-cmds-control.c
+++ b/monitor/qmp-cmds-control.c
@@ -76,7 +76,7 @@ void qmp_qmp_capabilities(bool has_enable, QMPCapabilityList *enable,
MonitorQMP *mon;
assert(monitor_is_qmp(cur_mon));
- mon = container_of(cur_mon, MonitorQMP, common);
+ mon = container_of(cur_mon, MonitorQMP, parent_obj);
if (mon->commands == &qmp_commands) {
error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND,
@@ -126,7 +126,7 @@ CommandInfoList *qmp_query_commands(Error **errp)
MonitorQMP *mon;
assert(monitor_is_qmp(cur_mon));
- mon = container_of(cur_mon, MonitorQMP, common);
+ mon = container_of(cur_mon, MonitorQMP, parent_obj);
qmp_for_each_command(mon->commands, query_commands_cb, &list);
diff --git a/monitor/qmp.c b/monitor/qmp.c
index 687019811f..27934206db 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -80,7 +80,7 @@ static void monitor_qmp_caps_reset(MonitorQMP *mon)
{
memset(mon->capab_offered, 0, sizeof(mon->capab_offered));
memset(mon->capab, 0, sizeof(mon->capab));
- mon->capab_offered[QMP_CAPABILITY_OOB] = mon->common.use_io_thread;
+ mon->capab_offered[QMP_CAPABILITY_OOB] = mon->parent_obj.use_io_thread;
}
static void qmp_request_free(QMPRequest *req)
@@ -124,7 +124,7 @@ static void monitor_qmp_cleanup_queue_and_resume(MonitorQMP *mon)
* when we get here while the monitor is suspended. An
* unfortunately timed CHR_EVENT_CLOSED can do the trick.
*/
- monitor_resume(&mon->common);
+ monitor_resume(&mon->parent_obj);
}
}
@@ -139,7 +139,7 @@ void qmp_send_response(MonitorQMP *mon, const QDict *rsp)
trace_monitor_qmp_respond(mon, json->str);
g_string_append_c(json, '\n');
- monitor_puts(&mon->common, json->str);
+ monitor_puts(&mon->parent_obj, json->str);
g_string_free(json, true);
}
@@ -166,7 +166,7 @@ static void monitor_qmp_dispatch(MonitorQMP *mon, QObject *req)
QDict *error;
rsp = qmp_dispatch(mon->commands, req, qmp_oob_enabled(mon),
- &mon->common);
+ &mon->parent_obj);
if (mon->commands == &qmp_cap_negotiation_commands) {
error = qdict_get_qdict(rsp, "error");
@@ -207,7 +207,7 @@ static QMPRequest *monitor_qmp_requests_pop_any_with_lock(void)
continue;
}
- qmp_mon = container_of(mon, MonitorQMP, common);
+ qmp_mon = container_of(mon, MonitorQMP, parent_obj);
qemu_mutex_lock(&qmp_mon->qmp_queue_lock);
req_obj = g_queue_pop_head(qmp_mon->qmp_requests);
if (req_obj) {
@@ -302,7 +302,7 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data)
oob_enabled = qmp_oob_enabled(mon);
if (oob_enabled
&& mon->qmp_requests->length == QMP_REQ_QUEUE_LEN_MAX - 1) {
- monitor_resume(&mon->common);
+ monitor_resume(&mon->parent_obj);
}
/*
@@ -343,7 +343,7 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data)
}
if (!oob_enabled) {
- monitor_resume(&mon->common);
+ monitor_resume(&mon->parent_obj);
}
qmp_request_free(req_obj);
@@ -408,7 +408,7 @@ static void handle_qmp_command(void *opaque, QObject *req, Error *err)
*/
if (!qmp_oob_enabled(mon) ||
mon->qmp_requests->length == QMP_REQ_QUEUE_LEN_MAX - 1) {
- monitor_suspend(&mon->common);
+ monitor_suspend(&mon->parent_obj);
}
/*
@@ -462,7 +462,7 @@ static void monitor_qmp_event(void *opaque, QEMUChrEvent event)
switch (event) {
case CHR_EVENT_OPENED:
- WITH_QEMU_LOCK_GUARD(&mon->common.mon_lock) {
+ WITH_QEMU_LOCK_GUARD(&mon->parent_obj.mon_lock) {
mon->commands = &qmp_cap_negotiation_commands;
monitor_qmp_caps_reset(mon);
}
@@ -504,27 +504,27 @@ static void monitor_qmp_setup_handlers_bh(void *opaque)
MonitorQMP *mon = opaque;
GMainContext *context;
- assert(mon->common.use_io_thread);
+ assert(mon->parent_obj.use_io_thread);
context = iothread_get_g_main_context(mon_iothread);
assert(context);
- qemu_chr_fe_set_handlers(&mon->common.chr, monitor_can_read,
+ qemu_chr_fe_set_handlers(&mon->parent_obj.chr, monitor_can_read,
monitor_qmp_read, monitor_qmp_event,
- NULL, &mon->common, context, true);
- monitor_list_append(&mon->common);
+ NULL, &mon->parent_obj, context, true);
+ monitor_list_append(&mon->parent_obj);
}
void monitor_init_qmp(Chardev *chr, bool pretty, Error **errp)
{
MonitorQMP *mon = g_new0(MonitorQMP, 1);
- if (!qemu_chr_fe_init(&mon->common.chr, chr, errp)) {
+ if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) {
g_free(mon);
return;
}
- qemu_chr_fe_set_echo(&mon->common.chr, true);
+ qemu_chr_fe_set_echo(&mon->parent_obj.chr, true);
/* Note: we run QMP monitor in I/O thread when @chr supports that */
- monitor_data_init(&mon->common, true, false,
+ monitor_data_init(&mon->parent_obj, true, false,
qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_GCONTEXT));
mon->pretty = pretty;
@@ -533,7 +533,7 @@ void monitor_init_qmp(Chardev *chr, bool pretty, Error **errp)
mon->qmp_requests = g_queue_new();
json_message_parser_init(&mon->parser, handle_qmp_command, mon, NULL);
- if (mon->common.use_io_thread) {
+ if (mon->parent_obj.use_io_thread) {
/*
* Make sure the old iowatch is gone. It's possible when
* e.g. the chardev is in client mode, with wait=on.
@@ -553,9 +553,9 @@ void monitor_init_qmp(Chardev *chr, bool pretty, Error **errp)
monitor_qmp_setup_handlers_bh, mon);
/* The bottom half will add @mon to @mon_list */
} else {
- qemu_chr_fe_set_handlers(&mon->common.chr, monitor_can_read,
+ qemu_chr_fe_set_handlers(&mon->parent_obj.chr, monitor_can_read,
monitor_qmp_read, monitor_qmp_event,
- NULL, &mon->common, NULL, true);
- monitor_list_append(&mon->common);
+ NULL, &mon->parent_obj, NULL, true);
+ monitor_list_append(&mon->parent_obj);
}
}
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 04/35] monitor: rename monitor_init* to monitor_new*
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (2 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 03/35] monitor: replace 'common' with 'parent_obj' in MonitorQMP Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 05/35] monitor: minimal conversion of monitors to QOM Daniel P. Berrangé
` (30 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
The current "monitor_init" functions will clash with the methods of the
same name that are required by QOM. To ease the transition to QOM,
rename them out of the way.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dave@treblig.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
chardev/char.c | 2 +-
gdbstub/system.c | 2 +-
include/monitor/monitor.h | 8 ++++----
monitor/hmp.c | 2 +-
monitor/monitor.c | 10 +++++-----
monitor/qmp.c | 2 +-
storage-daemon/qemu-storage-daemon.c | 2 +-
stubs/monitor-internal.c | 2 +-
system/vl.c | 2 +-
9 files changed, 16 insertions(+), 16 deletions(-)
diff --git a/chardev/char.c b/chardev/char.c
index ca8b37ed8d..813c04d953 100644
--- a/chardev/char.c
+++ b/chardev/char.c
@@ -805,7 +805,7 @@ static Chardev *qemu_chr_new_from_name(const char *label, const char *filename,
if (qemu_opt_get_bool(opts, "mux", 0)) {
assert(permit_mux_mon);
- monitor_init_hmp(chr, true, &err);
+ monitor_new_hmp(chr, true, &err);
if (err) {
error_report_err(err);
object_unparent(OBJECT(chr));
diff --git a/gdbstub/system.c b/gdbstub/system.c
index e86c5870ab..20dcf7878d 100644
--- a/gdbstub/system.c
+++ b/gdbstub/system.c
@@ -388,7 +388,7 @@ bool gdbserver_start(const char *device, Error **errp)
/* Initialize a monitor terminal for gdb */
mon_chr = qemu_chardev_new(NULL, TYPE_CHARDEV_GDB,
NULL, NULL, &error_abort);
- monitor_init_hmp(mon_chr, false, &error_abort);
+ monitor_new_hmp(mon_chr, false, &error_abort);
} else {
qemu_chr_fe_deinit(&gdbserver_system_state.chr, true);
mon_chr = gdbserver_system_state.mon_chr;
diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h
index 55649a8664..b9642b58ba 100644
--- a/include/monitor/monitor.h
+++ b/include/monitor/monitor.h
@@ -19,10 +19,10 @@ bool monitor_cur_is_qmp(void);
void monitor_init_globals(void);
void monitor_init_globals_core(void);
-void monitor_init_qmp(Chardev *chr, bool pretty, Error **errp);
-void monitor_init_hmp(Chardev *chr, bool use_readline, Error **errp);
-int monitor_init(MonitorOptions *opts, bool allow_hmp, Error **errp);
-int monitor_init_opts(QemuOpts *opts, Error **errp);
+void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp);
+void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp);
+int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp);
+int monitor_new_opts(QemuOpts *opts, Error **errp);
void monitor_cleanup(void);
int monitor_suspend(Monitor *mon);
diff --git a/monitor/hmp.c b/monitor/hmp.c
index 3dde52ddbe..4e4468424a 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -1524,7 +1524,7 @@ static void monitor_readline_flush(void *opaque)
monitor_flush(&mon->parent_obj);
}
-void monitor_init_hmp(Chardev *chr, bool use_readline, Error **errp)
+void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp)
{
MonitorHMP *mon = g_new0(MonitorHMP, 1);
diff --git a/monitor/monitor.c b/monitor/monitor.c
index 0b7b464ebe..a87597e606 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -715,7 +715,7 @@ void monitor_init_globals(void)
aio_co_schedule(iohandler_get_aio_context(), qmp_dispatcher_co);
}
-int monitor_init(MonitorOptions *opts, bool allow_hmp, Error **errp)
+int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
{
ERRP_GUARD();
Chardev *chr;
@@ -732,7 +732,7 @@ int monitor_init(MonitorOptions *opts, bool allow_hmp, Error **errp)
switch (opts->mode) {
case MONITOR_MODE_CONTROL:
- monitor_init_qmp(chr, opts->pretty, errp);
+ monitor_new_qmp(chr, opts->pretty, errp);
break;
case MONITOR_MODE_READLINE:
if (!allow_hmp) {
@@ -743,7 +743,7 @@ int monitor_init(MonitorOptions *opts, bool allow_hmp, Error **errp)
error_setg(errp, "'pretty' is not compatible with HMP monitors");
return -1;
}
- monitor_init_hmp(chr, true, errp);
+ monitor_new_hmp(chr, true, errp);
break;
default:
g_assert_not_reached();
@@ -752,7 +752,7 @@ int monitor_init(MonitorOptions *opts, bool allow_hmp, Error **errp)
return *errp ? -1 : 0;
}
-int monitor_init_opts(QemuOpts *opts, Error **errp)
+int monitor_new_opts(QemuOpts *opts, Error **errp)
{
Visitor *v;
MonitorOptions *options;
@@ -765,7 +765,7 @@ int monitor_init_opts(QemuOpts *opts, Error **errp)
return -1;
}
- ret = monitor_init(options, true, errp);
+ ret = monitor_new(options, true, errp);
qapi_free_MonitorOptions(options);
return ret;
}
diff --git a/monitor/qmp.c b/monitor/qmp.c
index 27934206db..cb28a95efd 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -513,7 +513,7 @@ static void monitor_qmp_setup_handlers_bh(void *opaque)
monitor_list_append(&mon->parent_obj);
}
-void monitor_init_qmp(Chardev *chr, bool pretty, Error **errp)
+void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp)
{
MonitorQMP *mon = g_new0(MonitorQMP, 1);
diff --git a/storage-daemon/qemu-storage-daemon.c b/storage-daemon/qemu-storage-daemon.c
index eb72561358..50dbfbd97a 100644
--- a/storage-daemon/qemu-storage-daemon.c
+++ b/storage-daemon/qemu-storage-daemon.c
@@ -330,7 +330,7 @@ static void process_options(int argc, char *argv[], bool pre_init_pass)
visit_free(v);
/* TODO Catch duplicate monitor IDs */
- monitor_init(monitor, false, &error_fatal);
+ monitor_new(monitor, false, &error_fatal);
qapi_free_MonitorOptions(monitor);
break;
}
diff --git a/stubs/monitor-internal.c b/stubs/monitor-internal.c
index 4fece49d53..23d58da184 100644
--- a/stubs/monitor-internal.c
+++ b/stubs/monitor-internal.c
@@ -8,6 +8,6 @@ int monitor_get_fd(Monitor *mon, const char *name, Error **errp)
return -1;
}
-void monitor_init_hmp(Chardev *chr, bool use_readline, Error **errp)
+void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp)
{
}
diff --git a/system/vl.c b/system/vl.c
index dbdd4f2257..21ef2dac51 100644
--- a/system/vl.c
+++ b/system/vl.c
@@ -1246,7 +1246,7 @@ static int fsdev_init_func(void *opaque, QemuOpts *opts, Error **errp)
static int mon_init_func(void *opaque, QemuOpts *opts, Error **errp)
{
- return monitor_init_opts(opts, errp);
+ return monitor_new_opts(opts, errp);
}
static void monitor_parse(const char *str, const char *mode, bool pretty)
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 05/35] monitor: minimal conversion of monitors to QOM
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (3 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 04/35] monitor: rename monitor_init* to monitor_new* Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 06/35] monitor: add 'chardev' property to Monitor base class Daniel P. Berrangé
` (29 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
This introduces a Monitor QOM object, with MonitorHMP and
MonitorQMP subclasses. This is the bare minimum conversion
of just the type declarations and replacing g_new/g_free
with object_new/object_unref.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
include/monitor/monitor.h | 11 ++++++++++-
monitor/hmp.c | 29 +++++++++++++++++++++++++++--
monitor/monitor-internal.h | 18 ++++++++++++++++--
monitor/monitor.c | 18 ++++++++++++++++--
monitor/qmp-cmds.c | 15 ++++++++-------
monitor/qmp.c | 29 +++++++++++++++++++++++++++--
6 files changed, 104 insertions(+), 16 deletions(-)
diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h
index b9642b58ba..2e9f9e12e9 100644
--- a/include/monitor/monitor.h
+++ b/include/monitor/monitor.h
@@ -5,8 +5,17 @@
#include "qapi/qapi-types-misc.h"
#include "qemu/readline.h"
#include "exec/hwaddr.h"
+#include "qom/object.h"
+
+#define TYPE_MONITOR "monitor"
+OBJECT_DECLARE_TYPE(Monitor, MonitorClass, MONITOR);
+
+#define TYPE_MONITOR_HMP "monitor-hmp"
+OBJECT_DECLARE_TYPE(MonitorHMP, MonitorHMPClass, MONITOR_HMP);
+
+#define TYPE_MONITOR_QMP "monitor-qmp"
+OBJECT_DECLARE_TYPE(MonitorQMP, MonitorQMPClass, MONITOR_QMP);
-typedef struct MonitorHMP MonitorHMP;
typedef struct MonitorOptions MonitorOptions;
#define QMP_REQ_QUEUE_LEN_MAX 8
diff --git a/monitor/hmp.c b/monitor/hmp.c
index 4e4468424a..81047d2513 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -43,6 +43,20 @@
#include "system/block-backend.h"
#include "trace.h"
+OBJECT_DEFINE_TYPE(MonitorHMP, monitor_hmp, MONITOR_HMP, MONITOR);
+
+static void monitor_hmp_finalize(Object *obj)
+{
+}
+
+static void monitor_hmp_class_init(ObjectClass *cls, const void *data)
+{
+}
+
+static void monitor_hmp_init(Object *obj)
+{
+}
+
static void monitor_command_cb(void *opaque, const char *cmdline,
void *readline_opaque)
{
@@ -1526,10 +1540,21 @@ static void monitor_readline_flush(void *opaque)
void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp)
{
- MonitorHMP *mon = g_new0(MonitorHMP, 1);
+ MonitorHMP *mon;
+ static int counter;
+ g_autofree char *id = g_strdup_printf("hmpcompat%d", counter++);
+ Object *obj = object_new_with_props(TYPE_MONITOR_HMP,
+ object_get_objects_root(),
+ id,
+ errp,
+ NULL);
+ if (!obj) {
+ return;
+ }
+ mon = MONITOR_HMP(obj);
if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) {
- g_free(mon);
+ object_unparent(OBJECT(mon));
return;
}
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index 4da2b2a677..05c1f2f5e0 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -101,7 +101,13 @@ typedef struct HMPCommand {
bool coroutine;
} HMPCommand;
+
+struct MonitorClass {
+ ObjectClass parent_class;
+};
+
struct Monitor {
+ Object parent;
CharFrontend chr;
int suspend_cnt; /* Needs to be accessed atomically */
bool is_qmp;
@@ -127,6 +133,10 @@ struct Monitor {
int reset_seen;
};
+struct MonitorHMPClass {
+ MonitorClass parent_class;
+};
+
struct MonitorHMP {
Monitor parent_obj;
bool use_readline;
@@ -140,7 +150,11 @@ struct MonitorHMP {
ReadLineState *rs;
};
-typedef struct {
+struct MonitorQMPClass {
+ MonitorClass parent_class;
+};
+
+struct MonitorQMP {
Monitor parent_obj;
JSONMessageParser parser;
bool pretty;
@@ -160,7 +174,7 @@ typedef struct {
QemuMutex qmp_queue_lock;
/* Input queue that holds all the parsed QMP requests */
GQueue *qmp_requests;
-} MonitorQMP;
+};
/**
* Is @mon a QMP monitor?
diff --git a/monitor/monitor.c b/monitor/monitor.c
index a87597e606..a497c25c54 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -73,6 +73,20 @@ static GHashTable *coroutine_mon; /* Maps Coroutine* to Monitor* */
MonitorList mon_list;
static bool monitor_destroyed;
+OBJECT_DEFINE_TYPE(Monitor, monitor, MONITOR, OBJECT);
+
+static void monitor_finalize(Object *obj)
+{
+}
+
+static void monitor_class_init(ObjectClass *cls, const void *data)
+{
+}
+
+static void monitor_init(Object *obj)
+{
+}
+
Monitor *monitor_cur(void)
{
Monitor *mon;
@@ -598,7 +612,7 @@ void monitor_list_append(Monitor *mon)
if (mon) {
monitor_data_destroy(mon);
- g_free(mon);
+ object_unparent(OBJECT(mon));
}
}
@@ -680,7 +694,7 @@ void monitor_cleanup(void)
monitor_flush(mon);
monitor_data_destroy(mon);
qemu_mutex_lock(&monitor_lock);
- g_free(mon);
+ object_unparent(OBJECT(mon));
}
qemu_mutex_unlock(&monitor_lock);
diff --git a/monitor/qmp-cmds.c b/monitor/qmp-cmds.c
index aa9ee8a391..bfde769ef0 100644
--- a/monitor/qmp-cmds.c
+++ b/monitor/qmp-cmds.c
@@ -166,12 +166,12 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
int64_t cpu_index, Error **errp)
{
char *output = NULL;
- MonitorHMP hmp = {};
+ MonitorHMP *hmp = MONITOR_HMP(object_new(TYPE_MONITOR_HMP));
- monitor_data_init(&hmp.parent_obj, false, true, false);
+ monitor_data_init(&hmp->parent_obj, false, true, false);
if (has_cpu_index) {
- int ret = monitor_set_cpu(&hmp.parent_obj, cpu_index);
+ int ret = monitor_set_cpu(&hmp->parent_obj, cpu_index);
if (ret < 0) {
error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cpu-index",
"a CPU number");
@@ -179,14 +179,15 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
}
}
- handle_hmp_command(&hmp, command_line);
+ handle_hmp_command(hmp, command_line);
- WITH_QEMU_LOCK_GUARD(&hmp.parent_obj.mon_lock) {
- output = g_strdup(hmp.parent_obj.outbuf->str);
+ WITH_QEMU_LOCK_GUARD(&hmp->parent_obj.mon_lock) {
+ output = g_strdup(hmp->parent_obj.outbuf->str);
}
out:
- monitor_data_destroy(&hmp.parent_obj);
+ monitor_data_destroy(&hmp->parent_obj);
+ object_unref(hmp);
return output;
}
diff --git a/monitor/qmp.c b/monitor/qmp.c
index cb28a95efd..5231ed506a 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -71,6 +71,20 @@ typedef struct QMPRequest QMPRequest;
QmpCommandList qmp_commands, qmp_cap_negotiation_commands;
+OBJECT_DEFINE_TYPE(MonitorQMP, monitor_qmp, MONITOR_QMP, MONITOR);
+
+static void monitor_qmp_finalize(Object *obj)
+{
+}
+
+static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
+{
+}
+
+static void monitor_qmp_init(Object *obj)
+{
+}
+
static bool qmp_oob_enabled(MonitorQMP *mon)
{
return mon->capab[QMP_CAPABILITY_OOB];
@@ -515,10 +529,21 @@ static void monitor_qmp_setup_handlers_bh(void *opaque)
void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp)
{
- MonitorQMP *mon = g_new0(MonitorQMP, 1);
+ MonitorQMP *mon;
+ static int counter;
+ g_autofree char *id = g_strdup_printf("qmpcompat%d", counter++);
+ Object *obj = object_new_with_props(TYPE_MONITOR_QMP,
+ object_get_objects_root(),
+ id,
+ errp,
+ NULL);
+ if (!obj) {
+ return;
+ }
+ mon = MONITOR_QMP(obj);
if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) {
- g_free(mon);
+ object_unparent(OBJECT(mon));
return;
}
qemu_chr_fe_set_echo(&mon->parent_obj.chr, true);
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 06/35] monitor: add 'chardev' property to Monitor base class
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (4 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 05/35] monitor: minimal conversion of monitors to QOM Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 11:54 ` marcandre.lureau
2026-06-18 10:58 ` [PATCH v3 07/35] monitor: add 'readline' property to HMP Monitor class Daniel P. Berrangé
` (28 subsequent siblings)
34 siblings, 1 reply; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
This is associates both QMP and HMP monitors with a character
device backend.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
chardev/char.c | 3 ++-
gdbstub/system.c | 4 ++--
include/monitor/monitor.h | 4 ++--
monitor/hmp.c | 10 ++++++--
monitor/monitor-internal.h | 2 ++
monitor/monitor.c | 47 ++++++++++++++++++++++++++++++--------
monitor/qmp.c | 18 ++++++++++-----
stubs/monitor-internal.c | 2 +-
8 files changed, 67 insertions(+), 23 deletions(-)
diff --git a/chardev/char.c b/chardev/char.c
index 813c04d953..981fbb1aaa 100644
--- a/chardev/char.c
+++ b/chardev/char.c
@@ -804,8 +804,9 @@ static Chardev *qemu_chr_new_from_name(const char *label, const char *filename,
}
if (qemu_opt_get_bool(opts, "mux", 0)) {
+ const char *chardev_id = qemu_opts_id(opts);
assert(permit_mux_mon);
- monitor_new_hmp(chr, true, &err);
+ monitor_new_hmp(chardev_id, true, &err);
if (err) {
error_report_err(err);
object_unparent(OBJECT(chr));
diff --git a/gdbstub/system.c b/gdbstub/system.c
index 20dcf7878d..920abda184 100644
--- a/gdbstub/system.c
+++ b/gdbstub/system.c
@@ -386,9 +386,9 @@ bool gdbserver_start(const char *device, Error **errp)
qemu_add_vm_change_state_handler(gdb_vm_state_change, NULL);
/* Initialize a monitor terminal for gdb */
- mon_chr = qemu_chardev_new(NULL, TYPE_CHARDEV_GDB,
+ mon_chr = qemu_chardev_new("gdbchrdev0", TYPE_CHARDEV_GDB,
NULL, NULL, &error_abort);
- monitor_new_hmp(mon_chr, false, &error_abort);
+ monitor_new_hmp("gdbchrdev0", false, &error_abort);
} else {
qemu_chr_fe_deinit(&gdbserver_system_state.chr, true);
mon_chr = gdbserver_system_state.mon_chr;
diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h
index 2e9f9e12e9..a135b3a590 100644
--- a/include/monitor/monitor.h
+++ b/include/monitor/monitor.h
@@ -28,8 +28,8 @@ bool monitor_cur_is_qmp(void);
void monitor_init_globals(void);
void monitor_init_globals_core(void);
-void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp);
-void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp);
+void monitor_new_qmp(const char *chardev_id, bool pretty, Error **errp);
+void monitor_new_hmp(const char *chardev_id, bool use_readline, Error **errp);
int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp);
int monitor_new_opts(QemuOpts *opts, Error **errp);
void monitor_cleanup(void);
diff --git a/monitor/hmp.c b/monitor/hmp.c
index 81047d2513..4ab81b5904 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -23,6 +23,7 @@
*/
#include "qemu/osdep.h"
+#include "qapi/error.h"
#include <dirent.h>
#include "hw/core/qdev.h"
#include "hw/core/sysemu-cpu-ops.h"
@@ -1538,8 +1539,9 @@ static void monitor_readline_flush(void *opaque)
monitor_flush(&mon->parent_obj);
}
-void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp)
+void monitor_new_hmp(const char *chardev_id, bool use_readline, Error **errp)
{
+ ERRP_GUARD();
MonitorHMP *mon;
static int counter;
g_autofree char *id = g_strdup_printf("hmpcompat%d", counter++);
@@ -1547,13 +1549,17 @@ void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp)
object_get_objects_root(),
id,
errp,
+ "chardev", chardev_id,
NULL);
+
if (!obj) {
return;
}
+
mon = MONITOR_HMP(obj);
- if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) {
+ monitor_complete(MONITOR(mon), errp);
+ if (*errp) {
object_unparent(OBJECT(mon));
return;
}
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index 05c1f2f5e0..145d52fd71 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -108,6 +108,7 @@ struct MonitorClass {
struct Monitor {
Object parent;
+ char *chardev_id;
CharFrontend chr;
int suspend_cnt; /* Needs to be accessed atomically */
bool is_qmp;
@@ -192,6 +193,7 @@ extern QmpCommandList qmp_commands, qmp_cap_negotiation_commands;
extern QemuMutex monitor_lock;
extern MonitorList mon_list;
+void monitor_complete(Monitor *mon, Error **errp);
void monitor_data_init(Monitor *mon, bool is_qmp, bool skip_flush,
bool use_io_thread);
void monitor_data_destroy(Monitor *mon);
diff --git a/monitor/monitor.c b/monitor/monitor.c
index a497c25c54..747ca27fd5 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -77,10 +77,31 @@ OBJECT_DEFINE_TYPE(Monitor, monitor, MONITOR, OBJECT);
static void monitor_finalize(Object *obj)
{
+ Monitor *mon = MONITOR(obj);
+
+ g_free(mon->chardev_id);
+}
+
+static char *monitor_get_chardev_id(Object *obj, Error **errp)
+{
+ Monitor *mon = MONITOR(obj);
+
+ return g_strdup(mon->chardev_id);
+}
+
+static void monitor_set_chardev_id(Object *obj, const char *str, Error **errp)
+{
+ Monitor *mon = MONITOR(obj);
+
+ g_free(mon->chardev_id);
+ mon->chardev_id = g_strdup(str);
}
static void monitor_class_init(ObjectClass *cls, const void *data)
{
+ object_class_property_add_str(cls, "chardev",
+ monitor_get_chardev_id,
+ monitor_set_chardev_id);
}
static void monitor_init(Object *obj)
@@ -729,16 +750,24 @@ void monitor_init_globals(void)
aio_co_schedule(iohandler_get_aio_context(), qmp_dispatcher_co);
}
-int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
+void monitor_complete(Monitor *mon, Error **errp)
{
- ERRP_GUARD();
- Chardev *chr;
+ if (mon->chardev_id) {
+ Chardev *chr = qemu_chr_find(mon->chardev_id);
+ if (chr == NULL) {
+ error_setg(errp, "chardev \"%s\" not found", mon->chardev_id);
+ return;
+ }
- chr = qemu_chr_find(opts->chardev);
- if (chr == NULL) {
- error_setg(errp, "chardev \"%s\" not found", opts->chardev);
- return -1;
+ if (!qemu_chr_fe_init(&mon->chr, chr, errp)) {
+ return;
+ }
}
+}
+
+int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
+{
+ ERRP_GUARD();
if (!opts->has_mode) {
opts->mode = allow_hmp ? MONITOR_MODE_READLINE : MONITOR_MODE_CONTROL;
@@ -746,7 +775,7 @@ int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
switch (opts->mode) {
case MONITOR_MODE_CONTROL:
- monitor_new_qmp(chr, opts->pretty, errp);
+ monitor_new_qmp(opts->chardev, opts->pretty, errp);
break;
case MONITOR_MODE_READLINE:
if (!allow_hmp) {
@@ -757,7 +786,7 @@ int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
error_setg(errp, "'pretty' is not compatible with HMP monitors");
return -1;
}
- monitor_new_hmp(chr, true, errp);
+ monitor_new_hmp(opts->chardev, true, errp);
break;
default:
g_assert_not_reached();
diff --git a/monitor/qmp.c b/monitor/qmp.c
index 5231ed506a..0abf2677f9 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -527,8 +527,9 @@ static void monitor_qmp_setup_handlers_bh(void *opaque)
monitor_list_append(&mon->parent_obj);
}
-void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp)
+void monitor_new_qmp(const char *chardev_id, bool pretty, Error **errp)
{
+ ERRP_GUARD();
MonitorQMP *mon;
static int counter;
g_autofree char *id = g_strdup_printf("qmpcompat%d", counter++);
@@ -536,21 +537,26 @@ void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp)
object_get_objects_root(),
id,
errp,
+ "chardev", chardev_id,
NULL);
+
if (!obj) {
return;
}
- mon = MONITOR_QMP(obj);
- if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) {
+ mon = MONITOR_QMP(obj);
+ monitor_complete(MONITOR(mon), errp);
+ if (*errp) {
object_unparent(OBJECT(mon));
return;
}
+
qemu_chr_fe_set_echo(&mon->parent_obj.chr, true);
/* Note: we run QMP monitor in I/O thread when @chr supports that */
monitor_data_init(&mon->parent_obj, true, false,
- qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_GCONTEXT));
+ qemu_chr_has_feature(mon->parent_obj.chr.chr,
+ QEMU_CHAR_FEATURE_GCONTEXT));
mon->pretty = pretty;
@@ -563,12 +569,12 @@ void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp)
* Make sure the old iowatch is gone. It's possible when
* e.g. the chardev is in client mode, with wait=on.
*/
- remove_fd_in_watch(chr);
+ remove_fd_in_watch(mon->parent_obj.chr.chr);
/*
* Clean up listener IO sources early to prevent racy fd
* handling between the main thread and the I/O thread.
*/
- remove_listener_fd_in_watch(chr);
+ remove_listener_fd_in_watch(mon->parent_obj.chr.chr);
/*
* We can't call qemu_chr_fe_set_handlers() directly here
* since chardev might be running in the monitor I/O
diff --git a/stubs/monitor-internal.c b/stubs/monitor-internal.c
index 23d58da184..51db7588b9 100644
--- a/stubs/monitor-internal.c
+++ b/stubs/monitor-internal.c
@@ -8,6 +8,6 @@ int monitor_get_fd(Monitor *mon, const char *name, Error **errp)
return -1;
}
-void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp)
+void monitor_new_hmp(const char *chardev_id, bool use_readline, Error **errp)
{
}
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* Re: [PATCH v3 06/35] monitor: add 'chardev' property to Monitor base class
2026-06-18 10:58 ` [PATCH v3 06/35] monitor: add 'chardev' property to Monitor base class Daniel P. Berrangé
@ 2026-06-18 11:54 ` marcandre.lureau
0 siblings, 0 replies; 43+ messages in thread
From: marcandre.lureau @ 2026-06-18 11:54 UTC (permalink / raw)
To: Daniel P. Berrangé
Cc: qemu-devel, devel, Alex Bennée, Christian Brauner,
Markus Armbruster, Marc-André Lureau, Dr. David Alan Gilbert,
Paolo Bonzini, Philippe Mathieu-Daudé
On Thu, 18 Jun 2026 11:58:07 +0100, Daniel P. Berrangé <berrange@redhat.com> wrote:
> This is associates both QMP and HMP monitors with a character
> device backend.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
--
Marc-André Lureau <marcandre.lureau@redhat.com>
^ permalink raw reply [flat|nested] 43+ messages in thread
* [PATCH v3 07/35] monitor: add 'readline' property to HMP Monitor class
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (5 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 06/35] monitor: add 'chardev' property to Monitor base class Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 08/35] monitor: add 'pretty' property to QMP " Daniel P. Berrangé
` (27 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
This determines whether a human monitor runs with readline for
interactive use, or without readline for non-interactive use by
the GDB stub.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/hmp.c | 27 ++++++++++++++++++++++++++-
1 file changed, 26 insertions(+), 1 deletion(-)
diff --git a/monitor/hmp.c b/monitor/hmp.c
index 4ab81b5904..d5905e2279 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -50,12 +50,37 @@ static void monitor_hmp_finalize(Object *obj)
{
}
+static bool monitor_hmp_get_readline(Object *obj, Error **errp)
+{
+ MonitorHMP *mon = MONITOR_HMP(obj);
+
+ return mon->use_readline;
+}
+
+static void monitor_hmp_set_readline(Object *obj, bool val, Error **errp)
+{
+ MonitorHMP *mon = MONITOR_HMP(obj);
+
+ mon->use_readline = val;
+}
+
static void monitor_hmp_class_init(ObjectClass *cls, const void *data)
{
+ object_class_property_add_bool(cls, "readline",
+ monitor_hmp_get_readline,
+ monitor_hmp_set_readline);
}
static void monitor_hmp_init(Object *obj)
{
+ MonitorHMP *hmp = MONITOR_HMP(obj);
+
+ /*
+ * Default to common case for external HMP use,
+ * as opposed to non-interactive internal use
+ * from gdbstub
+ */
+ hmp->use_readline = true;
}
static void monitor_command_cb(void *opaque, const char *cmdline,
@@ -1550,6 +1575,7 @@ void monitor_new_hmp(const char *chardev_id, bool use_readline, Error **errp)
id,
errp,
"chardev", chardev_id,
+ "readline", use_readline ? "yes" : "no",
NULL);
if (!obj) {
@@ -1566,7 +1592,6 @@ void monitor_new_hmp(const char *chardev_id, bool use_readline, Error **errp)
monitor_data_init(&mon->parent_obj, false, false, false);
- mon->use_readline = use_readline;
if (mon->use_readline) {
mon->rs = readline_init(monitor_readline_printf,
monitor_readline_flush,
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 08/35] monitor: add 'pretty' property to QMP Monitor class
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (6 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 07/35] monitor: add 'readline' property to HMP Monitor class Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 09/35] monitor: remove 'skip_flush' field Daniel P. Berrangé
` (26 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
This determines whether the QMP JSON responses are pretty printed
with newlines and indentation, or compact with no extra whitespace.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/qmp.c | 20 ++++++++++++++++++--
1 file changed, 18 insertions(+), 2 deletions(-)
diff --git a/monitor/qmp.c b/monitor/qmp.c
index 0abf2677f9..2a8532ef96 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -77,8 +77,25 @@ static void monitor_qmp_finalize(Object *obj)
{
}
+static bool monitor_qmp_get_pretty(Object *obj, Error **errp)
+{
+ MonitorQMP *mon = MONITOR_QMP(obj);
+
+ return mon->pretty;
+}
+
+static void monitor_qmp_set_pretty(Object *obj, bool val, Error **errp)
+{
+ MonitorQMP *mon = MONITOR_QMP(obj);
+
+ mon->pretty = val;
+}
+
static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
{
+ object_class_property_add_bool(cls, "pretty",
+ monitor_qmp_get_pretty,
+ monitor_qmp_set_pretty);
}
static void monitor_qmp_init(Object *obj)
@@ -538,6 +555,7 @@ void monitor_new_qmp(const char *chardev_id, bool pretty, Error **errp)
id,
errp,
"chardev", chardev_id,
+ "pretty", pretty ? "yes" : "no",
NULL);
if (!obj) {
@@ -558,8 +576,6 @@ void monitor_new_qmp(const char *chardev_id, bool pretty, Error **errp)
qemu_chr_has_feature(mon->parent_obj.chr.chr,
QEMU_CHAR_FEATURE_GCONTEXT));
- mon->pretty = pretty;
-
qemu_mutex_init(&mon->qmp_queue_lock);
mon->qmp_requests = g_queue_new();
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 09/35] monitor: remove 'skip_flush' field
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (7 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 08/35] monitor: add 'pretty' property to QMP " Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 10/35] monitor: move monitor_data_(init|destroy) into QOM init/finalize Daniel P. Berrangé
` (25 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
The 'skip_flush' field is set on the dummy throwaway HMP monitor
object created by QMP's 'human-monitor-command', as an indication
not to try to write data to the chardev. Instead the QMP command
impl will grab the data straight out of the in-memory buffer.
The flag is redundant, however, as the monitor code could instead
simply check the 'fe_is_open' field on the CharFrontend, which
will be false in the same scenarios that 'skip_flush' is true.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/hmp.c | 2 +-
monitor/monitor-internal.h | 4 +---
monitor/monitor.c | 11 +++++++----
monitor/qmp-cmds.c | 2 +-
monitor/qmp.c | 2 +-
5 files changed, 11 insertions(+), 10 deletions(-)
diff --git a/monitor/hmp.c b/monitor/hmp.c
index d5905e2279..516aa25d4c 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -1590,7 +1590,7 @@ void monitor_new_hmp(const char *chardev_id, bool use_readline, Error **errp)
return;
}
- monitor_data_init(&mon->parent_obj, false, false, false);
+ monitor_data_init(&mon->parent_obj, false, false);
if (mon->use_readline) {
mon->rs = readline_init(monitor_readline_printf,
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index 145d52fd71..d34f9be139 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -112,7 +112,6 @@ struct Monitor {
CharFrontend chr;
int suspend_cnt; /* Needs to be accessed atomically */
bool is_qmp;
- bool skip_flush;
bool use_io_thread;
char *mon_cpu_path;
@@ -194,8 +193,7 @@ extern QemuMutex monitor_lock;
extern MonitorList mon_list;
void monitor_complete(Monitor *mon, Error **errp);
-void monitor_data_init(Monitor *mon, bool is_qmp, bool skip_flush,
- bool use_io_thread);
+void monitor_data_init(Monitor *mon, bool is_qmp, bool use_io_thread);
void monitor_data_destroy(Monitor *mon);
int monitor_can_read(void *opaque);
void monitor_list_append(Monitor *mon);
diff --git a/monitor/monitor.c b/monitor/monitor.c
index 747ca27fd5..e3e5623a4b 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -188,7 +188,12 @@ void monitor_flush_locked(Monitor *mon)
size_t len;
const char *buf;
- if (mon->skip_flush) {
+ /*
+ * When used by QMP human-monitor-command, no chardev
+ * will be connected, as we want to just collect the
+ * output in the buffer
+ */
+ if (!mon->chr.fe_is_open) {
return;
}
@@ -642,8 +647,7 @@ static void monitor_iothread_init(void)
mon_iothread = iothread_create("mon_iothread", &error_abort);
}
-void monitor_data_init(Monitor *mon, bool is_qmp, bool skip_flush,
- bool use_io_thread)
+void monitor_data_init(Monitor *mon, bool is_qmp, bool use_io_thread)
{
if (use_io_thread && !mon_iothread) {
monitor_iothread_init();
@@ -651,7 +655,6 @@ void monitor_data_init(Monitor *mon, bool is_qmp, bool skip_flush,
qemu_mutex_init(&mon->mon_lock);
mon->is_qmp = is_qmp;
mon->outbuf = g_string_new(NULL);
- mon->skip_flush = skip_flush;
mon->use_io_thread = use_io_thread;
}
diff --git a/monitor/qmp-cmds.c b/monitor/qmp-cmds.c
index bfde769ef0..0d9adad288 100644
--- a/monitor/qmp-cmds.c
+++ b/monitor/qmp-cmds.c
@@ -168,7 +168,7 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
char *output = NULL;
MonitorHMP *hmp = MONITOR_HMP(object_new(TYPE_MONITOR_HMP));
- monitor_data_init(&hmp->parent_obj, false, true, false);
+ monitor_data_init(&hmp->parent_obj, false, false);
if (has_cpu_index) {
int ret = monitor_set_cpu(&hmp->parent_obj, cpu_index);
diff --git a/monitor/qmp.c b/monitor/qmp.c
index 2a8532ef96..e3318b57db 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -572,7 +572,7 @@ void monitor_new_qmp(const char *chardev_id, bool pretty, Error **errp)
qemu_chr_fe_set_echo(&mon->parent_obj.chr, true);
/* Note: we run QMP monitor in I/O thread when @chr supports that */
- monitor_data_init(&mon->parent_obj, true, false,
+ monitor_data_init(&mon->parent_obj, true,
qemu_chr_has_feature(mon->parent_obj.chr.chr,
QEMU_CHAR_FEATURE_GCONTEXT));
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 10/35] monitor: move monitor_data_(init|destroy) into QOM init/finalize
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (8 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 09/35] monitor: remove 'skip_flush' field Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 11/35] monitor: use class methods for monitor_vprintf Daniel P. Berrangé
` (24 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
Start to take advantage of QOM, by using object init and finalize
methods to replace monitor_data_init and monitor_data_destroy.
A standalone helper is provided to enable the I/O thread for QMP
where appropriate for the chardev backend.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/hmp.c | 6 +++--
monitor/monitor-internal.h | 3 +--
monitor/monitor.c | 46 +++++++++++++-------------------------
monitor/qmp-cmds.c | 3 ---
monitor/qmp.c | 34 +++++++++++++++-------------
5 files changed, 40 insertions(+), 52 deletions(-)
diff --git a/monitor/hmp.c b/monitor/hmp.c
index 516aa25d4c..2bb2333da5 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -48,6 +48,10 @@ OBJECT_DEFINE_TYPE(MonitorHMP, monitor_hmp, MONITOR_HMP, MONITOR);
static void monitor_hmp_finalize(Object *obj)
{
+ MonitorHMP *mon = MONITOR_HMP(obj);
+ if (mon->rs) {
+ readline_free(mon->rs);
+ }
}
static bool monitor_hmp_get_readline(Object *obj, Error **errp)
@@ -1590,8 +1594,6 @@ void monitor_new_hmp(const char *chardev_id, bool use_readline, Error **errp)
return;
}
- monitor_data_init(&mon->parent_obj, false, false);
-
if (mon->use_readline) {
mon->rs = readline_init(monitor_readline_printf,
monitor_readline_flush,
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index d34f9be139..6a4c3b0f37 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -193,8 +193,7 @@ extern QemuMutex monitor_lock;
extern MonitorList mon_list;
void monitor_complete(Monitor *mon, Error **errp);
-void monitor_data_init(Monitor *mon, bool is_qmp, bool use_io_thread);
-void monitor_data_destroy(Monitor *mon);
+void monitor_iothread_init(Monitor *mon);
int monitor_can_read(void *opaque);
void monitor_list_append(Monitor *mon);
void monitor_fdsets_cleanup(void);
diff --git a/monitor/monitor.c b/monitor/monitor.c
index e3e5623a4b..76df379a2c 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -80,6 +80,10 @@ static void monitor_finalize(Object *obj)
Monitor *mon = MONITOR(obj);
g_free(mon->chardev_id);
+ g_free(mon->mon_cpu_path);
+ qemu_chr_fe_deinit(&mon->chr, false);
+ g_string_free(mon->outbuf, true);
+ qemu_mutex_destroy(&mon->mon_lock);
}
static char *monitor_get_chardev_id(Object *obj, Error **errp)
@@ -106,6 +110,11 @@ static void monitor_class_init(ObjectClass *cls, const void *data)
static void monitor_init(Object *obj)
{
+ Monitor *mon = MONITOR(obj);
+
+ qemu_mutex_init(&mon->mon_lock);
+ mon->is_qmp = !!object_dynamic_cast(obj, TYPE_MONITOR_QMP);
+ mon->outbuf = g_string_new(NULL);
}
Monitor *monitor_cur(void)
@@ -637,38 +646,16 @@ void monitor_list_append(Monitor *mon)
qemu_mutex_unlock(&monitor_lock);
if (mon) {
- monitor_data_destroy(mon);
object_unparent(OBJECT(mon));
}
}
-static void monitor_iothread_init(void)
-{
- mon_iothread = iothread_create("mon_iothread", &error_abort);
-}
-
-void monitor_data_init(Monitor *mon, bool is_qmp, bool use_io_thread)
+void monitor_iothread_init(Monitor *mon)
{
- if (use_io_thread && !mon_iothread) {
- monitor_iothread_init();
+ if (!mon_iothread) {
+ mon_iothread = iothread_create("mon_iothread", &error_abort);
}
- qemu_mutex_init(&mon->mon_lock);
- mon->is_qmp = is_qmp;
- mon->outbuf = g_string_new(NULL);
- mon->use_io_thread = use_io_thread;
-}
-
-void monitor_data_destroy(Monitor *mon)
-{
- g_free(mon->mon_cpu_path);
- qemu_chr_fe_deinit(&mon->chr, false);
- if (monitor_is_qmp(mon)) {
- monitor_data_destroy_qmp(container_of(mon, MonitorQMP, parent_obj));
- } else {
- readline_free(container_of(mon, MonitorHMP, parent_obj)->rs);
- }
- g_string_free(mon->outbuf, true);
- qemu_mutex_destroy(&mon->mon_lock);
+ mon->use_io_thread = true;
}
void monitor_cleanup(void)
@@ -686,7 +673,7 @@ void monitor_cleanup(void)
* Letting the iothread continue while shutting down the dispatcher
* means that new requests may still be coming in. This is okay,
* we'll just leave them in the queue without sending a response
- * and monitor_data_destroy() will free them.
+ * and object finalization will free them.
*/
WITH_QEMU_LOCK_GUARD(&monitor_lock) {
qmp_dispatcher_co_shutdown = true;
@@ -700,8 +687,8 @@ void monitor_cleanup(void)
/*
* We need to explicitly stop the I/O thread (but not destroy it),
* clean up the monitor resources, then destroy the I/O thread since
- * we need to unregister from chardev below in
- * monitor_data_destroy(), and chardev is not thread-safe yet
+ * we need to unregister from chardev below in object
+ * finalization, and chardev is not thread-safe yet
*/
if (mon_iothread) {
iothread_stop(mon_iothread);
@@ -716,7 +703,6 @@ void monitor_cleanup(void)
/* Permit QAPI event emission from character frontend release */
qemu_mutex_unlock(&monitor_lock);
monitor_flush(mon);
- monitor_data_destroy(mon);
qemu_mutex_lock(&monitor_lock);
object_unparent(OBJECT(mon));
}
diff --git a/monitor/qmp-cmds.c b/monitor/qmp-cmds.c
index 0d9adad288..6cb0b587fb 100644
--- a/monitor/qmp-cmds.c
+++ b/monitor/qmp-cmds.c
@@ -168,8 +168,6 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
char *output = NULL;
MonitorHMP *hmp = MONITOR_HMP(object_new(TYPE_MONITOR_HMP));
- monitor_data_init(&hmp->parent_obj, false, false);
-
if (has_cpu_index) {
int ret = monitor_set_cpu(&hmp->parent_obj, cpu_index);
if (ret < 0) {
@@ -186,7 +184,6 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
}
out:
- monitor_data_destroy(&hmp->parent_obj);
object_unref(hmp);
return output;
}
diff --git a/monitor/qmp.c b/monitor/qmp.c
index e3318b57db..694d303215 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -73,8 +73,16 @@ QmpCommandList qmp_commands, qmp_cap_negotiation_commands;
OBJECT_DEFINE_TYPE(MonitorQMP, monitor_qmp, MONITOR_QMP, MONITOR);
+static void monitor_qmp_cleanup_req_queue_locked(MonitorQMP *mon);
+
static void monitor_qmp_finalize(Object *obj)
{
+ MonitorQMP *mon = MONITOR_QMP(obj);
+
+ json_message_parser_destroy(&mon->parser);
+ qemu_mutex_destroy(&mon->qmp_queue_lock);
+ monitor_qmp_cleanup_req_queue_locked(mon);
+ g_queue_free(mon->qmp_requests);
}
static bool monitor_qmp_get_pretty(Object *obj, Error **errp)
@@ -98,8 +106,15 @@ static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
monitor_qmp_set_pretty);
}
+static void handle_qmp_command(void *opaque, QObject *req, Error *err);
static void monitor_qmp_init(Object *obj)
{
+ MonitorQMP *mon = MONITOR_QMP(obj);
+
+ qemu_mutex_init(&mon->qmp_queue_lock);
+ mon->qmp_requests = g_queue_new();
+
+ json_message_parser_init(&mon->parser, handle_qmp_command, mon, NULL);
}
static bool qmp_oob_enabled(MonitorQMP *mon)
@@ -522,14 +537,6 @@ static void monitor_qmp_event(void *opaque, QEMUChrEvent event)
}
}
-void monitor_data_destroy_qmp(MonitorQMP *mon)
-{
- json_message_parser_destroy(&mon->parser);
- qemu_mutex_destroy(&mon->qmp_queue_lock);
- monitor_qmp_cleanup_req_queue_locked(mon);
- g_queue_free(mon->qmp_requests);
-}
-
static void monitor_qmp_setup_handlers_bh(void *opaque)
{
MonitorQMP *mon = opaque;
@@ -572,14 +579,11 @@ void monitor_new_qmp(const char *chardev_id, bool pretty, Error **errp)
qemu_chr_fe_set_echo(&mon->parent_obj.chr, true);
/* Note: we run QMP monitor in I/O thread when @chr supports that */
- monitor_data_init(&mon->parent_obj, true,
- qemu_chr_has_feature(mon->parent_obj.chr.chr,
- QEMU_CHAR_FEATURE_GCONTEXT));
-
- qemu_mutex_init(&mon->qmp_queue_lock);
- mon->qmp_requests = g_queue_new();
+ if (qemu_chr_has_feature(mon->parent_obj.chr.chr,
+ QEMU_CHAR_FEATURE_GCONTEXT)) {
+ monitor_iothread_init(&mon->parent_obj);
+ }
- json_message_parser_init(&mon->parser, handle_qmp_command, mon, NULL);
if (mon->parent_obj.use_io_thread) {
/*
* Make sure the old iowatch is gone. It's possible when
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 11/35] monitor: use class methods for monitor_vprintf
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (9 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 10/35] monitor: move monitor_data_(init|destroy) into QOM init/finalize Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 12/35] monitor: use class methods for monitor_qapi_event_emit Daniel P. Berrangé
` (23 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
This removes the need for using monitor_is_qmp() to check the
subclass type, which is an anti-pattern.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dave@treblig.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/hmp.c | 13 +++++++++++++
monitor/monitor-internal.h | 7 +++++++
monitor/monitor.c | 11 ++++-------
3 files changed, 24 insertions(+), 7 deletions(-)
diff --git a/monitor/hmp.c b/monitor/hmp.c
index 2bb2333da5..08055839a4 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -68,11 +68,18 @@ static void monitor_hmp_set_readline(Object *obj, bool val, Error **errp)
mon->use_readline = val;
}
+int monitor_hmp_vprintf(Monitor *mon, const char *fmt, va_list ap)
+ G_GNUC_PRINTF(2, 0);
+
static void monitor_hmp_class_init(ObjectClass *cls, const void *data)
{
+ MonitorClass *moncls = MONITOR_CLASS(cls);
+
object_class_property_add_bool(cls, "readline",
monitor_hmp_get_readline,
monitor_hmp_set_readline);
+
+ moncls->vprintf = monitor_hmp_vprintf;
}
static void monitor_hmp_init(Object *obj)
@@ -87,6 +94,12 @@ static void monitor_hmp_init(Object *obj)
hmp->use_readline = true;
}
+int monitor_hmp_vprintf(Monitor *mon, const char *fmt, va_list ap)
+{
+ g_autofree char *buf = g_strdup_vprintf(fmt, ap);
+ return monitor_puts(mon, buf);
+}
+
static void monitor_command_cb(void *opaque, const char *cmdline,
void *readline_opaque)
{
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index 6a4c3b0f37..23cef68153 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -104,6 +104,13 @@ typedef struct HMPCommand {
struct MonitorClass {
ObjectClass parent_class;
+
+ /*
+ * If non-NULL, the monitor is able to print messages
+ * for attention of the client user
+ */
+ int (*vprintf)(Monitor *mon, const char *fmt, va_list ap)
+ G_GNUC_PRINTF(2, 0);
};
struct Monitor {
diff --git a/monitor/monitor.c b/monitor/monitor.c
index 76df379a2c..8b70380d64 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -262,21 +262,18 @@ int monitor_puts(Monitor *mon, const char *str)
int monitor_vprintf(Monitor *mon, const char *fmt, va_list ap)
{
- char *buf;
- int n;
+ MonitorClass *moncls;
if (!mon) {
return -1;
}
- if (monitor_is_qmp(mon)) {
+ moncls = MONITOR_GET_CLASS(mon);
+ if (!moncls->vprintf) {
return -1;
}
- buf = g_strdup_vprintf(fmt, ap);
- n = monitor_puts(mon, buf);
- g_free(buf);
- return n;
+ return moncls->vprintf(mon, fmt, ap);
}
int monitor_printf(Monitor *mon, const char *fmt, ...)
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 12/35] monitor: use class methods for monitor_qapi_event_emit
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (10 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 11/35] monitor: use class methods for monitor_vprintf Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 13/35] monitor: use class methods for monitor_accept_input Daniel P. Berrangé
` (22 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
This removes the need for using monitor_is_qmp() to check the
subclass type, which is an anti-pattern.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
include/monitor/monitor.h | 1 +
monitor/monitor-internal.h | 5 +++++
monitor/monitor.c | 15 +++------------
monitor/qmp.c | 20 ++++++++++++++++++++
4 files changed, 29 insertions(+), 12 deletions(-)
diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h
index a135b3a590..8cb3db677b 100644
--- a/include/monitor/monitor.h
+++ b/include/monitor/monitor.h
@@ -3,6 +3,7 @@
#include "block/block.h"
#include "qapi/qapi-types-misc.h"
+#include "qapi/qapi-emit-events.h"
#include "qemu/readline.h"
#include "exec/hwaddr.h"
#include "qom/object.h"
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index 23cef68153..763b5c9625 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -111,6 +111,11 @@ struct MonitorClass {
*/
int (*vprintf)(Monitor *mon, const char *fmt, va_list ap)
G_GNUC_PRINTF(2, 0);
+ /*
+ * If non-NULL, the monitor is able to send event
+ * notifications back to the client
+ */
+ void (*emit_event)(Monitor *mon, QAPIEvent event, QDict *qdict);
};
struct Monitor {
diff --git a/monitor/monitor.c b/monitor/monitor.c
index 8b70380d64..6f0353d9f1 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -346,22 +346,13 @@ static inline QEMUClockType monitor_get_event_clock(void)
static void monitor_qapi_event_emit(QAPIEvent event, QDict *qdict)
{
Monitor *mon;
- MonitorQMP *qmp_mon;
trace_monitor_protocol_event_emit(event, qdict);
QTAILQ_FOREACH(mon, &mon_list, entry) {
- if (!monitor_is_qmp(mon)) {
- continue;
+ MonitorClass *cls = MONITOR_GET_CLASS(mon);
+ if (cls->emit_event) {
+ cls->emit_event(mon, event, qdict);
}
-
- qmp_mon = container_of(mon, MonitorQMP, parent_obj);
- {
- QEMU_LOCK_GUARD(&mon->mon_lock);
- if (qmp_mon->commands == &qmp_cap_negotiation_commands) {
- continue;
- }
- }
- qmp_send_response(qmp_mon, qdict);
}
}
diff --git a/monitor/qmp.c b/monitor/qmp.c
index 694d303215..ec17050a70 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -99,11 +99,17 @@ static void monitor_qmp_set_pretty(Object *obj, bool val, Error **errp)
mon->pretty = val;
}
+static void monitor_qmp_emit_event(Monitor *mon, QAPIEvent event, QDict *qdict);
+
static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
{
+ MonitorClass *moncls = MONITOR_CLASS(cls);
+
object_class_property_add_bool(cls, "pretty",
monitor_qmp_get_pretty,
monitor_qmp_set_pretty);
+
+ moncls->emit_event = monitor_qmp_emit_event;
}
static void handle_qmp_command(void *opaque, QObject *req, Error *err);
@@ -117,6 +123,20 @@ static void monitor_qmp_init(Object *obj)
json_message_parser_init(&mon->parser, handle_qmp_command, mon, NULL);
}
+static void monitor_qmp_emit_event(Monitor *mon, QAPIEvent event, QDict *qdict)
+{
+ MonitorQMP *qmp = MONITOR_QMP(mon);
+
+ WITH_QEMU_LOCK_GUARD(&mon->mon_lock) {
+ if (qmp->commands == &qmp_cap_negotiation_commands) {
+ return;
+ }
+ }
+
+ qmp_send_response(qmp, qdict);
+}
+
+
static bool qmp_oob_enabled(MonitorQMP *mon)
{
return mon->capab[QMP_CAPABILITY_OOB];
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 13/35] monitor: use class methods for monitor_accept_input
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (11 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 12/35] monitor: use class methods for monitor_qapi_event_emit Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 14/35] monitor: use class method for I/O thread request Daniel P. Berrangé
` (21 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
This removes the need for using monitor_is_qmp() to check the
subclass type, which is an anti-pattern.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/hmp.c | 16 ++++++++++++++++
monitor/monitor-internal.h | 5 +++++
monitor/monitor.c | 12 +++---------
3 files changed, 24 insertions(+), 9 deletions(-)
diff --git a/monitor/hmp.c b/monitor/hmp.c
index 08055839a4..1da9370ead 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -70,6 +70,7 @@ static void monitor_hmp_set_readline(Object *obj, bool val, Error **errp)
int monitor_hmp_vprintf(Monitor *mon, const char *fmt, va_list ap)
G_GNUC_PRINTF(2, 0);
+static void monitor_hmp_accept_input(Monitor *mon);
static void monitor_hmp_class_init(ObjectClass *cls, const void *data)
{
@@ -80,6 +81,7 @@ static void monitor_hmp_class_init(ObjectClass *cls, const void *data)
monitor_hmp_set_readline);
moncls->vprintf = monitor_hmp_vprintf;
+ moncls->accept_input = monitor_hmp_accept_input;
}
static void monitor_hmp_init(Object *obj)
@@ -100,6 +102,20 @@ int monitor_hmp_vprintf(Monitor *mon, const char *fmt, va_list ap)
return monitor_puts(mon, buf);
}
+static void monitor_hmp_accept_input(Monitor *mon)
+{
+ qemu_mutex_lock(&mon->mon_lock);
+ if (mon->reset_seen) {
+ MonitorHMP *hmp = MONITOR_HMP(mon);
+ assert(hmp->rs);
+ readline_restart(hmp->rs);
+ qemu_mutex_unlock(&mon->mon_lock);
+ readline_show_prompt(hmp->rs);
+ } else {
+ qemu_mutex_unlock(&mon->mon_lock);
+ }
+}
+
static void monitor_command_cb(void *opaque, const char *cmdline,
void *readline_opaque)
{
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index 763b5c9625..592f146331 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -116,6 +116,11 @@ struct MonitorClass {
* notifications back to the client
*/
void (*emit_event)(Monitor *mon, QAPIEvent event, QDict *qdict);
+ /*
+ * If non-NULL, perform any actions needed to prepare
+ * the monitor to accept further client input
+ */
+ void (*accept_input)(Monitor *mon);
};
struct Monitor {
diff --git a/monitor/monitor.c b/monitor/monitor.c
index 6f0353d9f1..2f16cd3053 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -576,16 +576,10 @@ int monitor_suspend(Monitor *mon)
static void monitor_accept_input(void *opaque)
{
Monitor *mon = opaque;
+ MonitorClass *cls = MONITOR_GET_CLASS(mon);
- qemu_mutex_lock(&mon->mon_lock);
- if (!monitor_is_qmp(mon) && mon->reset_seen) {
- MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, parent_obj);
- assert(hmp_mon->rs);
- readline_restart(hmp_mon->rs);
- qemu_mutex_unlock(&mon->mon_lock);
- readline_show_prompt(hmp_mon->rs);
- } else {
- qemu_mutex_unlock(&mon->mon_lock);
+ if (cls->accept_input) {
+ cls->accept_input(mon);
}
qemu_chr_fe_accept_input(&mon->chr);
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 14/35] monitor: use class method for I/O thread request
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (12 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 13/35] monitor: use class methods for monitor_accept_input Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 15/35] monitor: use dynamic cast in monitor_qmp_requests_pop_any_with_lock Daniel P. Berrangé
` (20 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
Introducing a virtual "requires_iothread" method allows the code to
automatically initialize the I/O thread during object completion.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/monitor-internal.h | 14 +++++++++-----
monitor/monitor.c | 22 ++++++++++++----------
monitor/qmp.c | 20 +++++++++++---------
3 files changed, 32 insertions(+), 24 deletions(-)
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index 592f146331..efd21b8912 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -121,6 +121,12 @@ struct MonitorClass {
* the monitor to accept further client input
*/
void (*accept_input)(Monitor *mon);
+
+ /*
+ * If non-NULL and returns true, then an I/O thread
+ * is required for processing the monitor
+ */
+ bool (*requires_iothread)(const Monitor *mon);
};
struct Monitor {
@@ -129,7 +135,6 @@ struct Monitor {
CharFrontend chr;
int suspend_cnt; /* Needs to be accessed atomically */
bool is_qmp;
- bool use_io_thread;
char *mon_cpu_path;
QTAILQ_ENTRY(Monitor) entry;
@@ -159,9 +164,8 @@ struct MonitorHMP {
bool use_readline;
/*
* State used only in the thread "owning" the monitor.
- * If @use_io_thread, this is @mon_iothread. (This does not actually happen
- * in the current state of the code.)
- * Else, it's the main thread.
+ * This is currently always the main thread, since
+ * HMP does not allow use of the I/O thread at this time.
* These members can be safely accessed without locks.
*/
ReadLineState *rs;
@@ -210,7 +214,7 @@ extern QemuMutex monitor_lock;
extern MonitorList mon_list;
void monitor_complete(Monitor *mon, Error **errp);
-void monitor_iothread_init(Monitor *mon);
+bool monitor_requires_iothread(const Monitor *mon);
int monitor_can_read(void *opaque);
void monitor_list_append(Monitor *mon);
void monitor_fdsets_cleanup(void);
diff --git a/monitor/monitor.c b/monitor/monitor.c
index 2f16cd3053..b788669f1f 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -160,6 +160,12 @@ bool monitor_cur_is_qmp(void)
return cur_mon && monitor_is_qmp(cur_mon);
}
+bool monitor_requires_iothread(const Monitor *mon)
+{
+ MonitorClass *cls = MONITOR_GET_CLASS(mon);
+ return cls->requires_iothread && cls->requires_iothread(mon);
+}
+
/**
* Is @mon is using readline?
* Note: not all HMP monitors use readline, e.g., gdbserver has a
@@ -561,7 +567,7 @@ int monitor_suspend(Monitor *mon)
qatomic_inc(&mon->suspend_cnt);
- if (mon->use_io_thread) {
+ if (monitor_requires_iothread(mon)) {
/*
* Kick I/O thread to make sure this takes effect. It'll be
* evaluated again in prepare() of the watch object.
@@ -594,7 +600,7 @@ void monitor_resume(Monitor *mon)
if (qatomic_dec_fetch(&mon->suspend_cnt) == 0) {
AioContext *ctx;
- if (mon->use_io_thread) {
+ if (monitor_requires_iothread(mon)) {
ctx = iothread_get_aio_context(mon_iothread);
} else {
ctx = qemu_get_aio_context();
@@ -632,14 +638,6 @@ void monitor_list_append(Monitor *mon)
}
}
-void monitor_iothread_init(Monitor *mon)
-{
- if (!mon_iothread) {
- mon_iothread = iothread_create("mon_iothread", &error_abort);
- }
- mon->use_io_thread = true;
-}
-
void monitor_cleanup(void)
{
/*
@@ -734,6 +732,10 @@ void monitor_complete(Monitor *mon, Error **errp)
return;
}
}
+
+ if (monitor_requires_iothread(mon) && !mon_iothread) {
+ mon_iothread = iothread_create("mon_iothread", &error_abort);
+ }
}
int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
diff --git a/monitor/qmp.c b/monitor/qmp.c
index ec17050a70..93f576c19d 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -100,6 +100,7 @@ static void monitor_qmp_set_pretty(Object *obj, bool val, Error **errp)
}
static void monitor_qmp_emit_event(Monitor *mon, QAPIEvent event, QDict *qdict);
+static bool monitor_qmp_requires_iothread(const Monitor *mon);
static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
{
@@ -110,6 +111,7 @@ static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
monitor_qmp_set_pretty);
moncls->emit_event = monitor_qmp_emit_event;
+ moncls->requires_iothread = monitor_qmp_requires_iothread;
}
static void handle_qmp_command(void *opaque, QObject *req, Error *err);
@@ -136,6 +138,11 @@ static void monitor_qmp_emit_event(Monitor *mon, QAPIEvent event, QDict *qdict)
qmp_send_response(qmp, qdict);
}
+static bool monitor_qmp_requires_iothread(const Monitor *mon)
+{
+ return qemu_chr_has_feature(mon->chr.chr,
+ QEMU_CHAR_FEATURE_GCONTEXT);
+}
static bool qmp_oob_enabled(MonitorQMP *mon)
{
@@ -146,7 +153,8 @@ static void monitor_qmp_caps_reset(MonitorQMP *mon)
{
memset(mon->capab_offered, 0, sizeof(mon->capab_offered));
memset(mon->capab, 0, sizeof(mon->capab));
- mon->capab_offered[QMP_CAPABILITY_OOB] = mon->parent_obj.use_io_thread;
+ mon->capab_offered[QMP_CAPABILITY_OOB] =
+ monitor_requires_iothread(MONITOR(mon));
}
static void qmp_request_free(QMPRequest *req)
@@ -562,7 +570,7 @@ static void monitor_qmp_setup_handlers_bh(void *opaque)
MonitorQMP *mon = opaque;
GMainContext *context;
- assert(mon->parent_obj.use_io_thread);
+ assert(monitor_requires_iothread(MONITOR(mon)));
context = iothread_get_g_main_context(mon_iothread);
assert(context);
qemu_chr_fe_set_handlers(&mon->parent_obj.chr, monitor_can_read,
@@ -598,13 +606,7 @@ void monitor_new_qmp(const char *chardev_id, bool pretty, Error **errp)
qemu_chr_fe_set_echo(&mon->parent_obj.chr, true);
- /* Note: we run QMP monitor in I/O thread when @chr supports that */
- if (qemu_chr_has_feature(mon->parent_obj.chr.chr,
- QEMU_CHAR_FEATURE_GCONTEXT)) {
- monitor_iothread_init(&mon->parent_obj);
- }
-
- if (mon->parent_obj.use_io_thread) {
+ if (monitor_requires_iothread(MONITOR(mon))) {
/*
* Make sure the old iowatch is gone. It's possible when
* e.g. the chardev is in client mode, with wait=on.
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 15/35] monitor: use dynamic cast in monitor_qmp_requests_pop_any_with_lock
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (13 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 14/35] monitor: use class method for I/O thread request Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 16/35] util: use dynamic cast in error vreport Daniel P. Berrangé
` (19 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
This eliminates a use of monitor_is_qmp() from the QMP coroutine
dispatch path.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/qmp.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/monitor/qmp.c b/monitor/qmp.c
index 93f576c19d..d2a03bb7e3 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -277,11 +277,12 @@ static QMPRequest *monitor_qmp_requests_pop_any_with_lock(void)
MonitorQMP *qmp_mon;
QTAILQ_FOREACH(mon, &mon_list, entry) {
- if (!monitor_is_qmp(mon)) {
+ qmp_mon = MONITOR_QMP(
+ object_dynamic_cast(OBJECT(mon), TYPE_MONITOR_QMP));
+ if (!qmp_mon) {
continue;
}
- qmp_mon = container_of(mon, MonitorQMP, parent_obj);
qemu_mutex_lock(&qmp_mon->qmp_queue_lock);
req_obj = g_queue_pop_head(qmp_mon->qmp_requests);
if (req_obj) {
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 16/35] util: use dynamic cast in error vreport
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (14 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 15/35] monitor: use dynamic cast in monitor_qmp_requests_pop_any_with_lock Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 17/35] monitor: drop unused monitor_cur_is_qmp Daniel P. Berrangé
` (18 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
This eliminates a use of monitor_is_qmp() from the error reporting
path.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
util/error-report.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/util/error-report.c b/util/error-report.c
index f832ad9b6b..f333af9249 100644
--- a/util/error-report.c
+++ b/util/error-report.c
@@ -231,16 +231,15 @@ char *real_time_iso8601(void)
G_GNUC_PRINTF(2, 0)
static void vreport(report_type type, const char *fmt, va_list ap)
{
- Monitor *cur = monitor_cur();
- gchar *timestr;
-
/*
* When current monitor is QMP, messages must go to stderr
- * and have prefixes added
+ * and have prefixes added, so we cast to HMP, leaving 'cur'
+ * as NULL in QMP case
*/
- if (monitor_cur_is_qmp()) {
- cur = NULL;
- }
+ Monitor *cur = MONITOR(
+ object_dynamic_cast(OBJECT(monitor_cur()), TYPE_MONITOR_HMP));
+ gchar *timestr;
+
if (!cur) {
qemu_flockfile(stderr);
}
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 17/35] monitor: drop unused monitor_cur_is_qmp
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (15 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 16/35] util: use dynamic cast in error vreport Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 18/35] monitor: use dynamic cast in QMP commands Daniel P. Berrangé
` (17 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
The previous patch dropped the only remaining use of
monitor_cur_is_qmp.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
include/monitor/monitor.h | 1 -
monitor/monitor.c | 10 ----------
stubs/monitor-core.c | 5 -----
tests/unit/test-util-sockets.c | 1 -
tools/qemu-vnc/stubs.c | 5 -----
5 files changed, 22 deletions(-)
diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h
index 8cb3db677b..3f730cffee 100644
--- a/include/monitor/monitor.h
+++ b/include/monitor/monitor.h
@@ -25,7 +25,6 @@ extern QemuOptsList qemu_mon_opts;
Monitor *monitor_cur(void);
Monitor *monitor_set_cur(Coroutine *co, Monitor *mon);
-bool monitor_cur_is_qmp(void);
void monitor_init_globals(void);
void monitor_init_globals_core(void);
diff --git a/monitor/monitor.c b/monitor/monitor.c
index b788669f1f..0db7903795 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -150,16 +150,6 @@ Monitor *monitor_set_cur(Coroutine *co, Monitor *mon)
return old_monitor;
}
-/**
- * Is the current monitor, if any, a QMP monitor?
- */
-bool monitor_cur_is_qmp(void)
-{
- Monitor *cur_mon = monitor_cur();
-
- return cur_mon && monitor_is_qmp(cur_mon);
-}
-
bool monitor_requires_iothread(const Monitor *mon)
{
MonitorClass *cls = MONITOR_GET_CLASS(mon);
diff --git a/stubs/monitor-core.c b/stubs/monitor-core.c
index 078a5012e9..a7c32297c9 100644
--- a/stubs/monitor-core.c
+++ b/stubs/monitor-core.c
@@ -7,11 +7,6 @@ Monitor *monitor_cur(void)
return NULL;
}
-bool monitor_cur_is_qmp(void)
-{
- return false;
-}
-
Monitor *monitor_set_cur(Coroutine *co, Monitor *mon)
{
return NULL;
diff --git a/tests/unit/test-util-sockets.c b/tests/unit/test-util-sockets.c
index b9f2453e29..ee66d727c3 100644
--- a/tests/unit/test-util-sockets.c
+++ b/tests/unit/test-util-sockets.c
@@ -74,7 +74,6 @@ int monitor_get_fd(Monitor *mon, const char *fdname, Error **errp)
Monitor *monitor_cur(void) { return cur_mon; }
Monitor *monitor_set_cur(Coroutine *co, Monitor *mon) { abort(); }
int monitor_vprintf(Monitor *mon, const char *fmt, va_list ap) { abort(); }
-bool monitor_cur_is_qmp(void) { abort(); };
#ifndef _WIN32
static void test_socket_fd_pass_name_good(void)
diff --git a/tools/qemu-vnc/stubs.c b/tools/qemu-vnc/stubs.c
index a865ce85f0..1c82d8cff4 100644
--- a/tools/qemu-vnc/stubs.c
+++ b/tools/qemu-vnc/stubs.c
@@ -36,11 +36,6 @@ Monitor *monitor_cur(void)
return NULL;
}
-bool monitor_cur_is_qmp(void)
-{
- return false;
-}
-
Monitor *monitor_set_cur(Coroutine *co, Monitor *mon)
{
return NULL;
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 18/35] monitor: use dynamic cast in QMP commands
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (16 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 17/35] monitor: drop unused monitor_cur_is_qmp Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 19/35] monitor: use dynamic cast in monitor_is_hmp_non_interactive Daniel P. Berrangé
` (16 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
Rather than asserting monitor_is_qmp(), use a QOM cast via
MONITOR_QMP which performs an assert already.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/qmp-cmds-control.c | 12 ++----------
1 file changed, 2 insertions(+), 10 deletions(-)
diff --git a/monitor/qmp-cmds-control.c b/monitor/qmp-cmds-control.c
index af6a2a118b..8fe0876a3d 100644
--- a/monitor/qmp-cmds-control.c
+++ b/monitor/qmp-cmds-control.c
@@ -72,11 +72,7 @@ static bool qmp_caps_accept(MonitorQMP *mon, QMPCapabilityList *list,
void qmp_qmp_capabilities(bool has_enable, QMPCapabilityList *enable,
Error **errp)
{
- Monitor *cur_mon = monitor_cur();
- MonitorQMP *mon;
-
- assert(monitor_is_qmp(cur_mon));
- mon = container_of(cur_mon, MonitorQMP, parent_obj);
+ MonitorQMP *mon = MONITOR_QMP(monitor_cur());
if (mon->commands == &qmp_commands) {
error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND,
@@ -122,11 +118,7 @@ static void query_commands_cb(const QmpCommand *cmd, void *opaque)
CommandInfoList *qmp_query_commands(Error **errp)
{
CommandInfoList *list = NULL;
- Monitor *cur_mon = monitor_cur();
- MonitorQMP *mon;
-
- assert(monitor_is_qmp(cur_mon));
- mon = container_of(cur_mon, MonitorQMP, parent_obj);
+ MonitorQMP *mon = MONITOR_QMP(monitor_cur());
qmp_for_each_command(mon->commands, query_commands_cb, &list);
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 19/35] monitor: use dynamic cast in monitor_is_hmp_non_interactive
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (17 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 18/35] monitor: use dynamic cast in QMP commands Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 20/35] monitor: drop unused monitor_is_qmp method Daniel P. Berrangé
` (15 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
Rather than checking !monitor_is_qmp(), use a dynamic cast to
check for HMP.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/monitor.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/monitor/monitor.c b/monitor/monitor.c
index 0db7903795..15e49d78d7 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -168,7 +168,7 @@ static inline bool monitor_uses_readline(const MonitorHMP *mon)
static inline bool monitor_is_hmp_non_interactive(const Monitor *mon)
{
- if (monitor_is_qmp(mon)) {
+ if (!object_dynamic_cast(OBJECT(mon), TYPE_MONITOR_HMP)) {
return false;
}
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 20/35] monitor: drop unused monitor_is_qmp method
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (18 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 19/35] monitor: use dynamic cast in monitor_is_hmp_non_interactive Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 21/35] monitor: eliminate monitor_is_hmp_non_interactive method Daniel P. Berrangé
` (14 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
The previous patch dropped the only remaining use of
monitor_is_qmp.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/monitor-internal.h | 9 ---------
monitor/monitor.c | 1 -
2 files changed, 10 deletions(-)
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index efd21b8912..fe5703af6d 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -134,7 +134,6 @@ struct Monitor {
char *chardev_id;
CharFrontend chr;
int suspend_cnt; /* Needs to be accessed atomically */
- bool is_qmp;
char *mon_cpu_path;
QTAILQ_ENTRY(Monitor) entry;
@@ -197,14 +196,6 @@ struct MonitorQMP {
GQueue *qmp_requests;
};
-/**
- * Is @mon a QMP monitor?
- */
-static inline bool monitor_is_qmp(const Monitor *mon)
-{
- return mon->is_qmp;
-}
-
typedef QTAILQ_HEAD(MonitorList, Monitor) MonitorList;
extern IOThread *mon_iothread;
extern Coroutine *qmp_dispatcher_co;
diff --git a/monitor/monitor.c b/monitor/monitor.c
index 15e49d78d7..6ed586fc4f 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -113,7 +113,6 @@ static void monitor_init(Object *obj)
Monitor *mon = MONITOR(obj);
qemu_mutex_init(&mon->mon_lock);
- mon->is_qmp = !!object_dynamic_cast(obj, TYPE_MONITOR_QMP);
mon->outbuf = g_string_new(NULL);
}
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 21/35] monitor: eliminate monitor_is_hmp_non_interactive method
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (19 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 20/35] monitor: drop unused monitor_is_qmp method Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 22/35] monitor: implement "user creatable" interface for adding monitors Daniel P. Berrangé
` (13 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
The monitor_is_hmp_non_interactive method is used by
monitor_suspend and monitor_resume, to make them a no-op
if the HMP does not use readline.
There are only a handful of callers of suspend/resume and
they can be made to skip the call when readline is not
present.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
include/monitor/monitor.h | 2 +-
migration/migration-hmp-cmds.c | 5 ++++-
monitor/hmp-cmds.c | 5 ++++-
monitor/hmp.c | 11 ++++++++---
monitor/monitor.c | 30 +-----------------------------
5 files changed, 18 insertions(+), 35 deletions(-)
diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h
index 3f730cffee..ffda343585 100644
--- a/include/monitor/monitor.h
+++ b/include/monitor/monitor.h
@@ -34,7 +34,7 @@ int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp);
int monitor_new_opts(QemuOpts *opts, Error **errp);
void monitor_cleanup(void);
-int monitor_suspend(Monitor *mon);
+void monitor_suspend(Monitor *mon);
void monitor_resume(Monitor *mon);
int monitor_get_fd(Monitor *mon, const char *fdname, Error **errp);
diff --git a/migration/migration-hmp-cmds.c b/migration/migration-hmp-cmds.c
index 8b385f560e..502ca704da 100644
--- a/migration/migration-hmp-cmds.c
+++ b/migration/migration-hmp-cmds.c
@@ -19,6 +19,7 @@
#include "monitor/hmp.h"
#include "monitor/hmp-completion.h"
#include "monitor/monitor.h"
+#include "monitor/monitor-internal.h"
#include "qapi/error.h"
#include "qapi/qapi-commands-migration.h"
#include "qapi/qapi-visit-migration.h"
@@ -853,12 +854,14 @@ void hmp_migrate(Monitor *mon, const QDict *qdict)
if (!detach) {
HMPMigrationStatus *status;
+ MonitorHMP *hmp = MONITOR_HMP(mon);
- if (monitor_suspend(mon) < 0) {
+ if (!hmp->use_readline) {
monitor_printf(mon, "terminal does not allow synchronous "
"migration, continuing detached\n");
return;
}
+ monitor_suspend(mon);
status = g_malloc0(sizeof(*status));
status->mon = mon;
diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
index e139caeba9..e9fb8d827a 100644
--- a/monitor/hmp-cmds.c
+++ b/monitor/hmp-cmds.c
@@ -129,7 +129,10 @@ void hmp_info_version(Monitor *mon, const QDict *qdict)
void hmp_quit(Monitor *mon, const QDict *qdict)
{
- monitor_suspend(mon);
+ MonitorHMP *hmp = MONITOR_HMP(mon);
+ if (hmp->use_readline) {
+ monitor_suspend(mon);
+ }
qmp_quit(NULL);
}
diff --git a/monitor/hmp.c b/monitor/hmp.c
index 1da9370ead..b8cccdcde3 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -1528,13 +1528,16 @@ static void monitor_read(void *opaque, const uint8_t *buf, int size)
static void monitor_event(void *opaque, QEMUChrEvent event)
{
Monitor *mon = opaque;
+ MonitorHMP *hmp = MONITOR_HMP(mon);
switch (event) {
case CHR_EVENT_MUX_IN:
qemu_mutex_lock(&mon->mon_lock);
if (mon->mux_out) {
mon->mux_out = 0;
- monitor_resume(mon);
+ if (hmp->use_readline) {
+ monitor_resume(mon);
+ }
}
qemu_mutex_unlock(&mon->mon_lock);
break;
@@ -1547,7 +1550,9 @@ static void monitor_event(void *opaque, QEMUChrEvent event)
} else {
monitor_flush_locked(mon);
}
- monitor_suspend(mon);
+ if (hmp->use_readline) {
+ monitor_suspend(mon);
+ }
mon->mux_out = 1;
}
qemu_mutex_unlock(&mon->mon_lock);
@@ -1558,7 +1563,7 @@ static void monitor_event(void *opaque, QEMUChrEvent event)
"information\n", QEMU_VERSION);
qemu_mutex_lock(&mon->mon_lock);
mon->reset_seen = 1;
- if (!mon->mux_out) {
+ if (!mon->mux_out && hmp->use_readline) {
/* Suspend-resume forces the prompt to be printed. */
monitor_suspend(mon);
monitor_resume(mon);
diff --git a/monitor/monitor.c b/monitor/monitor.c
index 6ed586fc4f..f88364a574 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -155,25 +155,6 @@ bool monitor_requires_iothread(const Monitor *mon)
return cls->requires_iothread && cls->requires_iothread(mon);
}
-/**
- * Is @mon is using readline?
- * Note: not all HMP monitors use readline, e.g., gdbserver has a
- * non-interactive HMP monitor, so readline is not used there.
- */
-static inline bool monitor_uses_readline(const MonitorHMP *mon)
-{
- return mon->use_readline;
-}
-
-static inline bool monitor_is_hmp_non_interactive(const Monitor *mon)
-{
- if (!object_dynamic_cast(OBJECT(mon), TYPE_MONITOR_HMP)) {
- return false;
- }
-
- return !monitor_uses_readline(container_of(mon, MonitorHMP, parent_obj));
-}
-
static gboolean monitor_unblocked(void *do_not_use, GIOCondition cond,
void *opaque)
{
@@ -548,12 +529,8 @@ static gboolean qapi_event_throttle_equal(const void *a, const void *b)
return TRUE;
}
-int monitor_suspend(Monitor *mon)
+void monitor_suspend(Monitor *mon)
{
- if (monitor_is_hmp_non_interactive(mon)) {
- return -ENOTTY;
- }
-
qatomic_inc(&mon->suspend_cnt);
if (monitor_requires_iothread(mon)) {
@@ -565,7 +542,6 @@ int monitor_suspend(Monitor *mon)
}
trace_monitor_suspend(mon, 1);
- return 0;
}
static void monitor_accept_input(void *opaque)
@@ -582,10 +558,6 @@ static void monitor_accept_input(void *opaque)
void monitor_resume(Monitor *mon)
{
- if (monitor_is_hmp_non_interactive(mon)) {
- return;
- }
-
if (qatomic_dec_fetch(&mon->suspend_cnt) == 0) {
AioContext *ctx;
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 22/35] monitor: implement "user creatable" interface for adding monitors
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (20 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 21/35] monitor: eliminate monitor_is_hmp_non_interactive method Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 23/35] monitor: convert from oneshot BH to persistent BH Daniel P. Berrangé
` (12 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
Implement the user creatable QOM interface and define the monitor-qmp
and monitor-hmp types in QAPI. This unlocks the ability to create them
on the command line with -object or in HMP/QMP with object_add.
For example:
$QEMU -chardev stdio,id=monchr0 -object monitor-hmp,id=mon0,chrdev=monchr0
Initially the "prepare_delete" callback is hardcoded to return an error
which means -object and object_add can be used, but object_del will fail.
Support for deleting monitors will be introduced in subsequent commits.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/hmp.c | 70 ++++++++++++++++++++++++--------------
monitor/monitor-internal.h | 1 -
monitor/monitor.c | 14 ++++++--
monitor/qmp.c | 46 +++++++++++++++++--------
qapi/qom.json | 43 +++++++++++++++++++++++
stubs/monitor-internal.c | 1 +
system/vl.c | 8 ++++-
7 files changed, 138 insertions(+), 45 deletions(-)
diff --git a/monitor/hmp.c b/monitor/hmp.c
index b8cccdcde3..2cd508f1ee 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -40,6 +40,7 @@
#include "qemu/base-arch-defs.h"
#include "qemu/target-info.h"
#include "qemu/units.h"
+#include "qom/object_interfaces.h"
#include "exec/gdbstub.h"
#include "system/block-backend.h"
#include "trace.h"
@@ -71,10 +72,13 @@ static void monitor_hmp_set_readline(Object *obj, bool val, Error **errp)
int monitor_hmp_vprintf(Monitor *mon, const char *fmt, va_list ap)
G_GNUC_PRINTF(2, 0);
static void monitor_hmp_accept_input(Monitor *mon);
+static void monitor_hmp_complete(UserCreatable *uc, Error **errp);
+static bool monitor_hmp_prepare_delete(UserCreatable *uc, Error **errp);
static void monitor_hmp_class_init(ObjectClass *cls, const void *data)
{
MonitorClass *moncls = MONITOR_CLASS(cls);
+ UserCreatableClass *ucc = USER_CREATABLE_CLASS(cls);
object_class_property_add_bool(cls, "readline",
monitor_hmp_get_readline,
@@ -82,6 +86,9 @@ static void monitor_hmp_class_init(ObjectClass *cls, const void *data)
moncls->vprintf = monitor_hmp_vprintf;
moncls->accept_input = monitor_hmp_accept_input;
+
+ ucc->complete = monitor_hmp_complete;
+ ucc->prepare_delete = monitor_hmp_prepare_delete;
}
static void monitor_hmp_init(Object *obj)
@@ -1604,42 +1611,53 @@ static void monitor_readline_flush(void *opaque)
void monitor_new_hmp(const char *chardev_id, bool use_readline, Error **errp)
{
- ERRP_GUARD();
- MonitorHMP *mon;
static int counter;
g_autofree char *id = g_strdup_printf("hmpcompat%d", counter++);
- Object *obj = object_new_with_props(TYPE_MONITOR_HMP,
- object_get_objects_root(),
- id,
- errp,
- "chardev", chardev_id,
- "readline", use_readline ? "yes" : "no",
- NULL);
-
- if (!obj) {
- return;
- }
+ object_new_with_props(TYPE_MONITOR_HMP,
+ object_get_objects_root(),
+ id,
+ errp,
+ "chardev", chardev_id,
+ "readline", use_readline ? "yes" : "no",
+ NULL);
+}
- mon = MONITOR_HMP(obj);
+static void monitor_hmp_complete(UserCreatable *uc, Error **errp)
+{
+ MonitorHMP *mon = MONITOR_HMP(uc);
+ UserCreatableClass *ucc_parent =
+ USER_CREATABLE_CLASS(
+ object_class_get_parent(
+ OBJECT_CLASS(MONITOR_HMP_GET_CLASS(mon))));
+ ERRP_GUARD();
- monitor_complete(MONITOR(mon), errp);
+ ucc_parent->complete(uc, errp);
if (*errp) {
- object_unparent(OBJECT(mon));
return;
}
- if (mon->use_readline) {
- mon->rs = readline_init(monitor_readline_printf,
- monitor_readline_flush,
- mon,
- monitor_find_completion);
- monitor_read_command(mon, 0);
+ if (mon->parent_obj.chardev_id) {
+ if (mon->use_readline) {
+ mon->rs = readline_init(monitor_readline_printf,
+ monitor_readline_flush,
+ mon,
+ monitor_find_completion);
+ monitor_read_command(mon, 0);
+ }
+
+ qemu_chr_fe_set_handlers(&mon->parent_obj.chr,
+ monitor_can_read,
+ monitor_read,
+ monitor_event, NULL,
+ &mon->parent_obj, NULL, true);
+ monitor_list_append(&mon->parent_obj);
}
+}
- qemu_chr_fe_set_handlers(&mon->parent_obj.chr,
- monitor_can_read, monitor_read, monitor_event,
- NULL, &mon->parent_obj, NULL, true);
- monitor_list_append(&mon->parent_obj);
+static bool monitor_hmp_prepare_delete(UserCreatable *uc, Error **errp)
+{
+ error_setg(errp, "Deleting HMP monitors is not supported");
+ return false;
}
/**
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index fe5703af6d..012d442a20 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -204,7 +204,6 @@ extern QmpCommandList qmp_commands, qmp_cap_negotiation_commands;
extern QemuMutex monitor_lock;
extern MonitorList mon_list;
-void monitor_complete(Monitor *mon, Error **errp);
bool monitor_requires_iothread(const Monitor *mon);
int monitor_can_read(void *opaque);
void monitor_list_append(Monitor *mon);
diff --git a/monitor/monitor.c b/monitor/monitor.c
index f88364a574..bf5e8a184a 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -29,6 +29,7 @@
#include "qapi/qapi-emit-events.h"
#include "qapi/qapi-visit-control.h"
#include "qobject/qdict.h"
+#include "qom/object_interfaces.h"
#include "qemu/error-report.h"
#include "qemu/option.h"
#include "system/qtest.h"
@@ -73,7 +74,8 @@ static GHashTable *coroutine_mon; /* Maps Coroutine* to Monitor* */
MonitorList mon_list;
static bool monitor_destroyed;
-OBJECT_DEFINE_TYPE(Monitor, monitor, MONITOR, OBJECT);
+OBJECT_DEFINE_TYPE_EXTENDED(Monitor, monitor, MONITOR, OBJECT, true,
+ { TYPE_USER_CREATABLE }, {});
static void monitor_finalize(Object *obj)
{
@@ -101,11 +103,17 @@ static void monitor_set_chardev_id(Object *obj, const char *str, Error **errp)
mon->chardev_id = g_strdup(str);
}
+static void monitor_complete(UserCreatable *uc, Error **errp);
+
static void monitor_class_init(ObjectClass *cls, const void *data)
{
+ UserCreatableClass *ucc = USER_CREATABLE_CLASS(cls);
+
object_class_property_add_str(cls, "chardev",
monitor_get_chardev_id,
monitor_set_chardev_id);
+
+ ucc->complete = monitor_complete;
}
static void monitor_init(Object *obj)
@@ -680,8 +688,10 @@ void monitor_init_globals(void)
aio_co_schedule(iohandler_get_aio_context(), qmp_dispatcher_co);
}
-void monitor_complete(Monitor *mon, Error **errp)
+static void monitor_complete(UserCreatable *uc, Error **errp)
{
+ Monitor *mon = MONITOR(uc);
+
if (mon->chardev_id) {
Chardev *chr = qemu_chr_find(mon->chardev_id);
if (chr == NULL) {
diff --git a/monitor/qmp.c b/monitor/qmp.c
index d2a03bb7e3..0e1c3eb52b 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -31,6 +31,7 @@
#include "qobject/qdict.h"
#include "qobject/qjson.h"
#include "qobject/qlist.h"
+#include "qom/object_interfaces.h"
#include "trace.h"
/*
@@ -101,10 +102,13 @@ static void monitor_qmp_set_pretty(Object *obj, bool val, Error **errp)
static void monitor_qmp_emit_event(Monitor *mon, QAPIEvent event, QDict *qdict);
static bool monitor_qmp_requires_iothread(const Monitor *mon);
+static void monitor_qmp_complete(UserCreatable *uc, Error **errp);
+static bool monitor_qmp_prepare_delete(UserCreatable *uc, Error **errp);
static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
{
MonitorClass *moncls = MONITOR_CLASS(cls);
+ UserCreatableClass *ucc = USER_CREATABLE_CLASS(cls);
object_class_property_add_bool(cls, "pretty",
monitor_qmp_get_pretty,
@@ -112,6 +116,9 @@ static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
moncls->emit_event = monitor_qmp_emit_event;
moncls->requires_iothread = monitor_qmp_requires_iothread;
+
+ ucc->complete = monitor_qmp_complete;
+ ucc->prepare_delete = monitor_qmp_prepare_delete;
}
static void handle_qmp_command(void *opaque, QObject *req, Error *err);
@@ -583,25 +590,28 @@ static void monitor_qmp_setup_handlers_bh(void *opaque)
void monitor_new_qmp(const char *chardev_id, bool pretty, Error **errp)
{
ERRP_GUARD();
- MonitorQMP *mon;
static int counter;
g_autofree char *id = g_strdup_printf("qmpcompat%d", counter++);
- Object *obj = object_new_with_props(TYPE_MONITOR_QMP,
- object_get_objects_root(),
- id,
- errp,
- "chardev", chardev_id,
- "pretty", pretty ? "yes" : "no",
- NULL);
-
- if (!obj) {
- return;
- }
+ object_new_with_props(TYPE_MONITOR_QMP,
+ object_get_objects_root(),
+ id,
+ errp,
+ "chardev", chardev_id,
+ "pretty", pretty ? "yes" : "no",
+ NULL);
+}
- mon = MONITOR_QMP(obj);
- monitor_complete(MONITOR(mon), errp);
+static void monitor_qmp_complete(UserCreatable *uc, Error **errp)
+{
+ MonitorQMP *mon = MONITOR_QMP(uc);
+ UserCreatableClass *ucc_parent =
+ USER_CREATABLE_CLASS(
+ object_class_get_parent(
+ OBJECT_CLASS(MONITOR_QMP_GET_CLASS(mon))));
+ ERRP_GUARD();
+
+ ucc_parent->complete(uc, errp);
if (*errp) {
- object_unparent(OBJECT(mon));
return;
}
@@ -633,3 +643,9 @@ void monitor_new_qmp(const char *chardev_id, bool pretty, Error **errp)
monitor_list_append(&mon->parent_obj);
}
}
+
+static bool monitor_qmp_prepare_delete(UserCreatable *uc, Error **errp)
+{
+ error_setg(errp, "Deleting QMP monitors is not supported");
+ return false;
+}
diff --git a/qapi/qom.json b/qapi/qom.json
index dd45ac1087..6ed510858e 100644
--- a/qapi/qom.json
+++ b/qapi/qom.json
@@ -1187,6 +1187,45 @@
'data': { '*cpu-affinity': ['uint16'],
'*node-affinity': ['uint16'] } }
+##
+# @MonitorProperties:
+#
+# Properties for all monitors
+#
+# @chardev: ID of the character device providing the monitor transport
+#
+# Since: 11.1
+##
+{ 'struct': 'MonitorProperties',
+ 'data': { 'chardev': 'str' }}
+
+##
+# @MonitorHMPProperties:
+#
+# Properties for the HMP monitor
+#
+# @readline: whether to enable readline for interactive command
+# usage (default: enabled)
+#
+# Since: 11.1
+##
+{ 'struct': 'MonitorHMPProperties',
+ 'base': 'MonitorProperties',
+ 'data': { '*readline': 'bool' } }
+
+##
+# @MonitorQMPProperties:
+#
+# Properties for the QMP monitor
+#
+# @pretty: whether to pretty print JSON responses (default: disabled)
+#
+# Since: 11.1
+##
+{ 'struct': 'MonitorQMPProperties',
+ 'base': 'MonitorProperties',
+ 'data': { '*pretty': 'bool' } }
+
##
# @ObjectType:
#
@@ -1237,6 +1276,8 @@
'memory-backend-ram',
{ 'name': 'memory-backend-shm',
'if': 'CONFIG_POSIX' },
+ 'monitor-hmp',
+ 'monitor-qmp',
'pef-guest',
{ 'name': 'pr-manager-helper',
'if': 'CONFIG_LINUX' },
@@ -1315,6 +1356,8 @@
'memory-backend-ram': 'MemoryBackendProperties',
'memory-backend-shm': { 'type': 'MemoryBackendShmProperties',
'if': 'CONFIG_POSIX' },
+ 'monitor-hmp': {'type': 'MonitorHMPProperties' },
+ 'monitor-qmp': {'type': 'MonitorQMPProperties' },
'pr-manager-helper': { 'type': 'PrManagerHelperProperties',
'if': 'CONFIG_LINUX' },
'qtest': 'QtestProperties',
diff --git a/stubs/monitor-internal.c b/stubs/monitor-internal.c
index 51db7588b9..59ccc4b35c 100644
--- a/stubs/monitor-internal.c
+++ b/stubs/monitor-internal.c
@@ -10,4 +10,5 @@ int monitor_get_fd(Monitor *mon, const char *name, Error **errp)
void monitor_new_hmp(const char *chardev_id, bool use_readline, Error **errp)
{
+ g_assert_not_reached();
}
diff --git a/system/vl.c b/system/vl.c
index 21ef2dac51..86f09a8b5c 100644
--- a/system/vl.c
+++ b/system/vl.c
@@ -1829,6 +1829,10 @@ static void object_option_add_visitor(Visitor *v)
{
ObjectOption *opt = g_new0(ObjectOption, 1);
visit_type_ObjectOptions(v, NULL, &opt->opts, &error_fatal);
+ if (opt->opts->qom_type == OBJECT_TYPE_MONITOR_HMP ||
+ opt->opts->qom_type == OBJECT_TYPE_MONITOR_QMP) {
+ default_monitor = 0;
+ }
QTAILQ_INSERT_TAIL(&object_opts, opt, next);
}
@@ -1970,7 +1974,9 @@ static bool object_create_early(const char *type)
/* Reason: property "chardev" */
if (g_str_equal(type, "rng-egd") ||
- g_str_equal(type, "qtest")) {
+ g_str_equal(type, "qtest") ||
+ g_str_equal(type, "monitor-hmp") ||
+ g_str_equal(type, "monitor-qmp")) {
return false;
}
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 23/35] monitor: convert from oneshot BH to persistent BH
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (21 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 22/35] monitor: implement "user creatable" interface for adding monitors Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 24/35] monitor: reject attempts to delete the current monitor Daniel P. Berrangé
` (11 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
From: Christian Brauner <brauner@kernel.org>
Convert monitor_accept_input from a oneshot BH (aio_bh_schedule_oneshot)
to a persistent BH (aio_bh_new + qemu_bh_schedule). Oneshot BHs cannot
be cancelled, so monitor_resume() racing with destruction would schedule
a callback against memory that monitor_qmp_destroy() is about to free.
A persistent BH can be deleted during destruction, cancelling any
pending schedule.
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
[DB: extracted oneshot BH conversion from larger commit]
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/monitor-internal.h | 2 +-
monitor/monitor.c | 25 ++++++++++++++-----------
2 files changed, 15 insertions(+), 12 deletions(-)
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index 012d442a20..a82e1aacb6 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -134,7 +134,7 @@ struct Monitor {
char *chardev_id;
CharFrontend chr;
int suspend_cnt; /* Needs to be accessed atomically */
-
+ QEMUBH *accept_input_bh; /* persistent BH for monitor_accept_input */
char *mon_cpu_path;
QTAILQ_ENTRY(Monitor) entry;
diff --git a/monitor/monitor.c b/monitor/monitor.c
index bf5e8a184a..312e069bc5 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -81,6 +81,9 @@ static void monitor_finalize(Object *obj)
{
Monitor *mon = MONITOR(obj);
+ if (mon->accept_input_bh) {
+ qemu_bh_delete(mon->accept_input_bh);
+ }
g_free(mon->chardev_id);
g_free(mon->mon_cpu_path);
qemu_chr_fe_deinit(&mon->chr, false);
@@ -567,15 +570,7 @@ static void monitor_accept_input(void *opaque)
void monitor_resume(Monitor *mon)
{
if (qatomic_dec_fetch(&mon->suspend_cnt) == 0) {
- AioContext *ctx;
-
- if (monitor_requires_iothread(mon)) {
- ctx = iothread_get_aio_context(mon_iothread);
- } else {
- ctx = qemu_get_aio_context();
- }
-
- aio_bh_schedule_oneshot(ctx, monitor_accept_input, mon);
+ qemu_bh_schedule(mon->accept_input_bh);
}
trace_monitor_suspend(mon, -1);
@@ -691,6 +686,7 @@ void monitor_init_globals(void)
static void monitor_complete(UserCreatable *uc, Error **errp)
{
Monitor *mon = MONITOR(uc);
+ AioContext *ctx;
if (mon->chardev_id) {
Chardev *chr = qemu_chr_find(mon->chardev_id);
@@ -704,9 +700,16 @@ static void monitor_complete(UserCreatable *uc, Error **errp)
}
}
- if (monitor_requires_iothread(mon) && !mon_iothread) {
- mon_iothread = iothread_create("mon_iothread", &error_abort);
+ if (monitor_requires_iothread(mon)) {
+ if (!mon_iothread) {
+ mon_iothread = iothread_create("mon_iothread", &error_abort);
+ }
+
+ ctx = iothread_get_aio_context(mon_iothread);
+ } else {
+ ctx = qemu_get_aio_context();
}
+ mon->accept_input_bh = aio_bh_new(ctx, monitor_accept_input, mon);
}
int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 24/35] monitor: reject attempts to delete the current monitor
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (22 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 23/35] monitor: convert from oneshot BH to persistent BH Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 25/35] monitor: protect qemu_chr_fe_accept_input with monitor lock Daniel P. Berrangé
` (10 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
From: Christian Brauner <brauner@kernel.org>
If an 'object_del' command for a QMP monitor arrives targetting the
current monitor, reject this request. If the current monitor is
deleted, it will be impossible to send any reply and the client won't
be able to remove the corresponding chardev backend.
Note, it is not possible to rely on checking monitor_cur() because
if 'object_del' is called via human-monitor-command, monitor_cur()
will reflect the temporary HMP, not the QMP target that needs to
be checked.
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
[DB: extracted monitor tracking from larger commit; added logic
to monitor_qmp_prepare_delete to reject request]
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/qmp.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/monitor/qmp.c b/monitor/qmp.c
index 0e1c3eb52b..b0535dec68 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -72,6 +72,9 @@ typedef struct QMPRequest QMPRequest;
QmpCommandList qmp_commands, qmp_cap_negotiation_commands;
+/* Monitor being serviced by the dispatcher. Protected by BQL. */
+static MonitorQMP *qmp_dispatcher_current_mon;
+
OBJECT_DEFINE_TYPE(MonitorQMP, monitor_qmp, MONITOR_QMP, MONITOR);
static void monitor_qmp_cleanup_req_queue_locked(MonitorQMP *mon);
@@ -369,6 +372,7 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data)
*/
mon = req_obj->mon;
+ qmp_dispatcher_current_mon = mon;
/*
* We need to resume the monitor if handle_qmp_command()
@@ -429,6 +433,7 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data)
}
qmp_request_free(req_obj);
+ qmp_dispatcher_current_mon = NULL;
}
qatomic_set(&qmp_dispatcher_co, NULL);
}
@@ -573,6 +578,11 @@ static void monitor_qmp_event(void *opaque, QEMUChrEvent event)
}
}
+static bool monitor_qmp_dispatcher_is_servicing(MonitorQMP *mon)
+{
+ return qmp_dispatcher_current_mon == mon;
+}
+
static void monitor_qmp_setup_handlers_bh(void *opaque)
{
MonitorQMP *mon = opaque;
@@ -646,6 +656,13 @@ static void monitor_qmp_complete(UserCreatable *uc, Error **errp)
static bool monitor_qmp_prepare_delete(UserCreatable *uc, Error **errp)
{
+ MonitorQMP *qmp = MONITOR_QMP(uc);
+
+ if (monitor_qmp_dispatcher_is_servicing(qmp)) {
+ error_setg(errp, "Cannot delete the current QMP monitor");
+ return false;
+ }
+
error_setg(errp, "Deleting QMP monitors is not supported");
return false;
}
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 25/35] monitor: protect qemu_chr_fe_accept_input with monitor lock
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (23 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 24/35] monitor: reject attempts to delete the current monitor Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 26/35] monitor: implement support for deleting QMP objects Daniel P. Berrangé
` (9 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
From: Christian Brauner <brauner@kernel.org>
The monitor_accept_input API is called from a bottom half, and will
invoke qemu_chr_fe_accept_input().
When a following patch introduces the ability to delete monitors, it
will be neccesary to delete the bottom half. Protecting the call to
qemu_chr_fe_accept_input with the monitor lock will allow for
synchronization with the deletion process.
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
[DB: extracted from a larger commit and refactored to apply
to the new monitor class structure]
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/hmp.c | 2 ++
monitor/monitor.c | 6 +-----
monitor/qmp.c | 9 +++++++++
3 files changed, 12 insertions(+), 5 deletions(-)
diff --git a/monitor/hmp.c b/monitor/hmp.c
index 2cd508f1ee..7b084c6ff8 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -116,9 +116,11 @@ static void monitor_hmp_accept_input(Monitor *mon)
MonitorHMP *hmp = MONITOR_HMP(mon);
assert(hmp->rs);
readline_restart(hmp->rs);
+ qemu_chr_fe_accept_input(&mon->chr);
qemu_mutex_unlock(&mon->mon_lock);
readline_show_prompt(hmp->rs);
} else {
+ qemu_chr_fe_accept_input(&mon->chr);
qemu_mutex_unlock(&mon->mon_lock);
}
}
diff --git a/monitor/monitor.c b/monitor/monitor.c
index 312e069bc5..0e1c623555 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -560,11 +560,7 @@ static void monitor_accept_input(void *opaque)
Monitor *mon = opaque;
MonitorClass *cls = MONITOR_GET_CLASS(mon);
- if (cls->accept_input) {
- cls->accept_input(mon);
- }
-
- qemu_chr_fe_accept_input(&mon->chr);
+ cls->accept_input(mon);
}
void monitor_resume(Monitor *mon)
diff --git a/monitor/qmp.c b/monitor/qmp.c
index b0535dec68..2131be82c7 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -107,6 +107,7 @@ static void monitor_qmp_emit_event(Monitor *mon, QAPIEvent event, QDict *qdict);
static bool monitor_qmp_requires_iothread(const Monitor *mon);
static void monitor_qmp_complete(UserCreatable *uc, Error **errp);
static bool monitor_qmp_prepare_delete(UserCreatable *uc, Error **errp);
+static void monitor_qmp_accept_input(Monitor *mon);
static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
{
@@ -119,6 +120,7 @@ static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
moncls->emit_event = monitor_qmp_emit_event;
moncls->requires_iothread = monitor_qmp_requires_iothread;
+ moncls->accept_input = monitor_qmp_accept_input;
ucc->complete = monitor_qmp_complete;
ucc->prepare_delete = monitor_qmp_prepare_delete;
@@ -666,3 +668,10 @@ static bool monitor_qmp_prepare_delete(UserCreatable *uc, Error **errp)
error_setg(errp, "Deleting QMP monitors is not supported");
return false;
}
+
+static void monitor_qmp_accept_input(Monitor *mon)
+{
+ WITH_QEMU_LOCK_GUARD(&mon->mon_lock) {
+ qemu_chr_fe_accept_input(&mon->chr);
+ }
+}
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 26/35] monitor: implement support for deleting QMP objects
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (24 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 25/35] monitor: protect qemu_chr_fe_accept_input with monitor lock Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 11:54 ` marcandre.lureau
2026-06-18 10:58 ` [PATCH v3 27/35] tests/qtest: add tests for dynamic monitor add/remove Daniel P. Berrangé
` (8 subsequent siblings)
34 siblings, 1 reply; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
From: Christian Brauner <brauner@kernel.org>
The removal sequence is:
1. Remove from mon_list under monitor_lock. This must happen
before disconnecting chardev handlers to prevent event
broadcast from calling monitor_flush_locked() after the
gcontext reset, which would create an out_watch on the wrong
GMainContext (see monitor_cancel_out_watch()).
2. Cancel any pending out_watch while gcontext still points to the
correct context.
3. Disconnect chardev handlers, passing context=NULL and close
the connection.
4. Drain pending requests from any in-flight monitor_qmp_read().
5. Destroy the monitor object
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
[DB: extracted from a larger commit and refactored to apply
to the new monitor class structure. Remove 'self delete'
feature which requires complex special-case code]
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/monitor-internal.h | 2 ++
monitor/monitor.c | 22 ++++++++++++++++
monitor/qmp.c | 54 ++++++++++++++++++++++++++++++++++++--
3 files changed, 76 insertions(+), 2 deletions(-)
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index a82e1aacb6..5522e05464 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -178,6 +178,7 @@ struct MonitorQMP {
Monitor parent_obj;
JSONMessageParser parser;
bool pretty;
+ bool setup_pending; /* iothread BH has not yet set up chardev handlers */
/*
* When a client connects, we're in capabilities negotiation mode.
* @commands is &qmp_cap_negotiation_commands then. When command
@@ -206,6 +207,7 @@ extern MonitorList mon_list;
bool monitor_requires_iothread(const Monitor *mon);
int monitor_can_read(void *opaque);
+void monitor_cancel_out_watch(Monitor *mon);
void monitor_list_append(Monitor *mon);
void monitor_fdsets_cleanup(void);
int monitor_set_cpu(Monitor *mon, int cpu_index);
diff --git a/monitor/monitor.c b/monitor/monitor.c
index 0e1c623555..b155f58546 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -177,6 +177,28 @@ static gboolean monitor_unblocked(void *do_not_use, GIOCondition cond,
return G_SOURCE_REMOVE;
}
+/* Cancel a pending out_watch GSource. Caller must hold mon_lock. */
+void monitor_cancel_out_watch(Monitor *mon)
+{
+ if (mon->out_watch) {
+ GMainContext *ctx = NULL;
+ GSource *src;
+
+ if (monitor_requires_iothread(mon)) {
+ ctx = iothread_get_g_main_context(mon_iothread);
+ }
+ src = g_main_context_find_source_by_id(ctx, mon->out_watch);
+ if (!src && ctx) {
+ /* Handler disconnect may have reset gcontext to NULL. */
+ src = g_main_context_find_source_by_id(NULL, mon->out_watch);
+ }
+ if (src) {
+ g_source_destroy(src);
+ }
+ mon->out_watch = 0;
+ }
+}
+
/* Caller must hold mon->mon_lock */
void monitor_flush_locked(Monitor *mon)
{
diff --git a/monitor/qmp.c b/monitor/qmp.c
index 2131be82c7..5301927f09 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -184,6 +184,12 @@ static void monitor_qmp_cleanup_req_queue_locked(MonitorQMP *mon)
}
}
+static void monitor_qmp_drain_queue(MonitorQMP *mon)
+{
+ QEMU_LOCK_GUARD(&mon->qmp_queue_lock);
+ monitor_qmp_cleanup_req_queue_locked(mon);
+}
+
static void monitor_qmp_cleanup_queue_and_resume(MonitorQMP *mon)
{
QEMU_LOCK_GUARD(&mon->qmp_queue_lock);
@@ -597,6 +603,7 @@ static void monitor_qmp_setup_handlers_bh(void *opaque)
monitor_qmp_read, monitor_qmp_event,
NULL, &mon->parent_obj, context, true);
monitor_list_append(&mon->parent_obj);
+ qatomic_set(&mon->setup_pending, false);
}
void monitor_new_qmp(const char *chardev_id, bool pretty, Error **errp)
@@ -645,6 +652,7 @@ static void monitor_qmp_complete(UserCreatable *uc, Error **errp)
* since chardev might be running in the monitor I/O
* thread. Schedule a bottom half.
*/
+ mon->setup_pending = true;
aio_bh_schedule_oneshot(iothread_get_aio_context(mon_iothread),
monitor_qmp_setup_handlers_bh, mon);
/* The bottom half will add @mon to @mon_list */
@@ -656,8 +664,14 @@ static void monitor_qmp_complete(UserCreatable *uc, Error **errp)
}
}
+static void monitor_qmp_iothread_quiesce(void *opaque)
+{
+ /* No-op: synchronization point only */
+}
+
static bool monitor_qmp_prepare_delete(UserCreatable *uc, Error **errp)
{
+ Monitor *mon = MONITOR(uc);
MonitorQMP *qmp = MONITOR_QMP(uc);
if (monitor_qmp_dispatcher_is_servicing(qmp)) {
@@ -665,8 +679,44 @@ static bool monitor_qmp_prepare_delete(UserCreatable *uc, Error **errp)
return false;
}
- error_setg(errp, "Deleting QMP monitors is not supported");
- return false;
+ if (qatomic_read(&qmp->setup_pending)) {
+ error_setg(errp, "monitor is still initializing");
+ return false;
+ }
+
+ /* Remove from mon_list before chardev disconnect. */
+ WITH_QEMU_LOCK_GUARD(&monitor_lock) {
+ QTAILQ_REMOVE(&mon_list, mon, entry);
+ }
+
+ /* Cancel out_watch while gcontext still points to the right ctx. */
+ WITH_QEMU_LOCK_GUARD(&mon->mon_lock) {
+ monitor_cancel_out_watch(mon);
+ }
+
+ qemu_chr_fe_set_handlers(&mon->chr, NULL, NULL, NULL, NULL,
+ NULL, NULL, true);
+
+ /* Drain requests from any in-flight monitor_qmp_read(). */
+ monitor_qmp_drain_queue(qmp);
+
+ WITH_QEMU_LOCK_GUARD(&mon->mon_lock) {
+ /* Disable flushes before cancel -- gcontext is already wrong. */
+ qemu_chr_fe_set_open(&mon->chr, false);
+ monitor_cancel_out_watch(mon);
+ }
+
+ /* Synchronize with in-flight iothread callbacks. */
+ if (monitor_requires_iothread(mon)) {
+ aio_wait_bh_oneshot(iothread_get_aio_context(mon_iothread),
+ monitor_qmp_iothread_quiesce, NULL);
+ }
+
+ /* Catch requests from a racing monitor_qmp_read(). */
+ monitor_qmp_drain_queue(qmp);
+ monitor_fdsets_cleanup();
+
+ return true;
}
static void monitor_qmp_accept_input(Monitor *mon)
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* Re: [PATCH v3 26/35] monitor: implement support for deleting QMP objects
2026-06-18 10:58 ` [PATCH v3 26/35] monitor: implement support for deleting QMP objects Daniel P. Berrangé
@ 2026-06-18 11:54 ` marcandre.lureau
0 siblings, 0 replies; 43+ messages in thread
From: marcandre.lureau @ 2026-06-18 11:54 UTC (permalink / raw)
To: Daniel P. Berrangé
Cc: qemu-devel, devel, Alex Bennée, Christian Brauner,
Markus Armbruster, Marc-André Lureau, Dr. David Alan Gilbert,
Paolo Bonzini, Philippe Mathieu-Daudé
On Thu, 18 Jun 2026 11:58:27 +0100, Daniel P. Berrangé <berrange@redhat.com> wrote:
> The removal sequence is:
>
> 1. Remove from mon_list under monitor_lock. This must happen
> before disconnecting chardev handlers to prevent event
> broadcast from calling monitor_flush_locked() after the
> gcontext reset, which would create an out_watch on the wrong
> GMainContext (see monitor_cancel_out_watch()).
> 2. Cancel any pending out_watch while gcontext still points to the
> correct context.
> 3. Disconnect chardev handlers, passing context=NULL and close
> the connection.
> 4. Drain pending requests from any in-flight monitor_qmp_read().
> 5. Destroy the monitor object
>
> [...]
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
--
Marc-André Lureau <marcandre.lureau@redhat.com>
^ permalink raw reply [flat|nested] 43+ messages in thread
* [PATCH v3 27/35] tests/qtest: add tests for dynamic monitor add/remove
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (25 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 26/35] monitor: implement support for deleting QMP objects Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 28/35] tests/functional: add e2e test for dynamic QMP monitor hotplug Daniel P. Berrangé
` (7 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
From: Christian Brauner <brauner@kernel.org>
Test the object-add/object-del QMP commands with the monitor-qmp
object type.
- Basic lifecycle: chardev-add -> object-add -> object-del -> chardev-remove
- Error: object-add with nonexistent chardev
- Error: second monitor on same chardev (chardev already in use)
- Removal of CLI-created QMP monitor succeeds
- Error: object-remove on HMP monitor
- Re-add after remove: same id and chardev reusable after removal
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
[DB: modified to use object-add/object-del, removing redundant
scenarios already handled by object-add/del code]
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
tests/qtest/qmp-test.c | 174 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 174 insertions(+)
diff --git a/tests/qtest/qmp-test.c b/tests/qtest/qmp-test.c
index edf0886787..3a325a04e0 100644
--- a/tests/qtest/qmp-test.c
+++ b/tests/qtest/qmp-test.c
@@ -337,6 +337,174 @@ static void test_qmp_missing_any_arg(void)
qtest_quit(qts);
}
+static void test_qmp_monitor_add_remove(void)
+{
+ QTestState *qts;
+ QDict *resp;
+
+ qts = qtest_init(common_args);
+
+ /* Create a null chardev for the dynamic monitor */
+ resp = qtest_qmp(qts,
+ "{'execute': 'chardev-add',"
+ " 'arguments': {'id': 'monitor-chardev',"
+ " 'backend': {'type': 'null',"
+ " 'data': {}}}}");
+ g_assert(qdict_haskey(resp, "return"));
+ qobject_unref(resp);
+
+ /* Add a dynamic monitor */
+ resp = qtest_qmp(qts,
+ "{'execute': 'object-add',"
+ " 'arguments': {'qom-type': 'monitor-qmp',"
+ " 'id': 'dyn-mon',"
+ " 'chardev': 'monitor-chardev'}}");
+ g_assert(qdict_haskey(resp, "return"));
+ qobject_unref(resp);
+
+ /* Remove the dynamic monitor */
+ resp = qtest_qmp(qts,
+ "{'execute': 'object-del',"
+ " 'arguments': {'id': 'dyn-mon'}}");
+ g_assert(qdict_haskey(resp, "return"));
+ qobject_unref(resp);
+
+ /* Add again after remove -- same id and chardev should work */
+ resp = qtest_qmp(qts,
+ "{'execute': 'object-add',"
+ " 'arguments': {'qom-type': 'monitor-qmp',"
+ " 'id': 'dyn-mon',"
+ " 'chardev': 'monitor-chardev'}}");
+ g_assert(qdict_haskey(resp, "return"));
+ qobject_unref(resp);
+
+ /* Clean up */
+ resp = qtest_qmp(qts,
+ "{'execute': 'object-del',"
+ " 'arguments': {'id': 'dyn-mon'}}");
+ g_assert(qdict_haskey(resp, "return"));
+ qobject_unref(resp);
+
+ resp = qtest_qmp(qts,
+ "{'execute': 'chardev-remove',"
+ " 'arguments': {'id': 'monitor-chardev'}}");
+ g_assert(qdict_haskey(resp, "return"));
+ qobject_unref(resp);
+
+ qtest_quit(qts);
+}
+
+static void test_qmp_monitor_error_paths(void)
+{
+ QTestState *qts;
+ QDict *resp;
+
+ qts = qtest_init(common_args);
+
+ /* Error: chardev does not exist */
+ resp = qtest_qmp(qts,
+ "{'execute': 'object-add',"
+ " 'arguments': {'qom-type': 'monitor-qmp',"
+ " 'id': 'bad-mon',"
+ " 'chardev': 'nonexistent'}}");
+ qmp_expect_error_and_unref(resp, "GenericError");
+
+ qtest_quit(qts);
+}
+
+static void test_qmp_monitor_chardev_in_use(void)
+{
+ QTestState *qts;
+ QDict *resp;
+
+ qts = qtest_init(common_args);
+
+ /* Create a null chardev */
+ resp = qtest_qmp(qts,
+ "{'execute': 'chardev-add',"
+ " 'arguments': {'id': 'shared-chr',"
+ " 'backend': {'type': 'null',"
+ " 'data': {}}}}");
+ g_assert(qdict_haskey(resp, "return"));
+ qobject_unref(resp);
+
+ /* Attach first monitor */
+ resp = qtest_qmp(qts,
+ "{'execute': 'object-add',"
+ " 'arguments': {'qom-type': 'monitor-qmp',"
+ " 'id': 'mon-1',"
+ " 'chardev': 'shared-chr'}}");
+ g_assert(qdict_haskey(resp, "return"));
+ qobject_unref(resp);
+
+ /* Error: second monitor on the same chardev */
+ resp = qtest_qmp(qts,
+ "{'execute': 'object-add',"
+ " 'arguments': {'qom-type': 'monitor-qmp',"
+ " 'id': 'mon-2',"
+ " 'chardev': 'shared-chr'}}");
+ qmp_expect_error_and_unref(resp, "GenericError");
+
+ /* Clean up */
+ resp = qtest_qmp(qts,
+ "{'execute': 'object-del',"
+ " 'arguments': {'id': 'mon-1'}}");
+ g_assert(qdict_haskey(resp, "return"));
+ qobject_unref(resp);
+
+ resp = qtest_qmp(qts,
+ "{'execute': 'chardev-remove',"
+ " 'arguments': {'id': 'shared-chr'}}");
+ g_assert(qdict_haskey(resp, "return"));
+ qobject_unref(resp);
+
+ qtest_quit(qts);
+}
+
+static void test_qmp_monitor_remove_cli(void)
+{
+ QTestState *qts;
+ QDict *resp;
+
+ /* Launch with a named CLI monitor on a null chardev */
+ qts = qtest_initf("%s -chardev null,id=cli-chr"
+ " -object monitor-qmp,id=cli-mon,chardev=cli-chr",
+ common_args);
+
+ /* CLI-created QMP monitors can be removed */
+ resp = qtest_qmp(qts,
+ "{'execute': 'object-del',"
+ " 'arguments': {'id': 'cli-mon'}}");
+ g_assert(qdict_haskey(resp, "return"));
+ qobject_unref(resp);
+
+ resp = qtest_qmp(qts,
+ "{'execute': 'chardev-remove',"
+ " 'arguments': {'id': 'cli-chr'}}");
+ g_assert(qdict_haskey(resp, "return"));
+ qobject_unref(resp);
+
+ qtest_quit(qts);
+}
+
+static void test_qmp_monitor_remove_hmp(void)
+{
+ QTestState *qts;
+ QDict *resp;
+
+ qts = qtest_initf("%s -chardev null,id=hmp-chr"
+ " -object monitor-hmp,id=hmp-mon,chardev=hmp-chr",
+ common_args);
+
+ /* Error: object_del must reject HMP monitors */
+ resp = qtest_qmp(qts,
+ "{'execute': 'object-del',"
+ " 'arguments': {'id': 'hmp-mon'}}");
+ qmp_expect_error_and_unref(resp, "GenericError");
+
+ qtest_quit(qts);
+}
+
int main(int argc, char *argv[])
{
g_test_init(&argc, &argv, NULL);
@@ -348,6 +516,12 @@ int main(int argc, char *argv[])
#endif
qtest_add_func("qmp/preconfig", test_qmp_preconfig);
qtest_add_func("qmp/missing-any-arg", test_qmp_missing_any_arg);
+ qtest_add_func("qmp/monitor-add-remove", test_qmp_monitor_add_remove);
+ qtest_add_func("qmp/monitor-error-paths", test_qmp_monitor_error_paths);
+ qtest_add_func("qmp/monitor-chardev-in-use",
+ test_qmp_monitor_chardev_in_use);
+ qtest_add_func("qmp/monitor-remove-cli", test_qmp_monitor_remove_cli);
+ qtest_add_func("qmp/monitor-remove-hmp", test_qmp_monitor_remove_hmp);
return g_test_run();
}
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 28/35] tests/functional: add e2e test for dynamic QMP monitor hotplug
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (26 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 27/35] tests/qtest: add tests for dynamic monitor add/remove Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 29/35] tests/functional: add a stress test for monitor hot unplug Daniel P. Berrangé
` (6 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
From: Christian Brauner <brauner@kernel.org>
Add functional tests that exercise dynamic monitor hotplug with real
socket connections:
- Hotplug cycle: chardev-add a unix socket, object-add, connect to the
socket, receive the QMP greeting, negotiate capabilities, send
query-version, disconnect, remove the monitor and chardev, then repeat
the entire cycle a second time to verify cleanup and reuse.
- Self-removal: a dynamically-added monitor sends object-del
targeting itself, verifying that the request is rejected
- Large response: send query-qmp-schema on a dynamic monitor to
exercise the output buffer flush path with a large response payload.
- Events after negotiation: trigger STOP/RESUME events via the main
monitor and verify they are delivered on the dynamic monitor.
This complements the qtest unit tests by verifying that a real QMP
client can connect to a dynamically-added monitor and exchange messages.
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
[DB: modified to use object-add/object-del; adjust self-removal test
to validate rejection of request]
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
MAINTAINERS | 1 +
tests/functional/generic/meson.build | 1 +
.../generic/test_monitor_hotplug.py | 168 ++++++++++++++++++
3 files changed, 170 insertions(+)
create mode 100755 tests/functional/generic/test_monitor_hotplug.py
diff --git a/MAINTAINERS b/MAINTAINERS
index 93df53d87f..c74ffe56ae 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3616,6 +3616,7 @@ F: docs/interop/*qmp-*
F: scripts/qmp/
F: tests/qtest/qmp-test.c
F: tests/qtest/qmp-cmd-test.c
+F: tests/functional/generic/test_monitor_hotplug.py
T: git https://repo.or.cz/qemu/armbru.git qapi-next
qtest
diff --git a/tests/functional/generic/meson.build b/tests/functional/generic/meson.build
index 09763c5d22..c94105c62e 100644
--- a/tests/functional/generic/meson.build
+++ b/tests/functional/generic/meson.build
@@ -4,6 +4,7 @@ tests_generic_system = [
'empty_cpu_model',
'info_usernet',
'linters',
+ 'monitor_hotplug',
'version',
'vnc',
]
diff --git a/tests/functional/generic/test_monitor_hotplug.py b/tests/functional/generic/test_monitor_hotplug.py
new file mode 100755
index 0000000000..5d8a159eb0
--- /dev/null
+++ b/tests/functional/generic/test_monitor_hotplug.py
@@ -0,0 +1,168 @@
+#!/usr/bin/env python3
+#
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Functional test for dynamic QMP monitor hotplug
+#
+# Copyright (c) 2026 Christian Brauner
+
+import os
+
+from qemu_test import QemuSystemTest
+
+from qemu.qmp.legacy import QEMUMonitorProtocol
+
+
+class MonitorHotplug(QemuSystemTest):
+
+ def setUp(self):
+ super().setUp()
+ sock_dir = self.socket_dir()
+ self._sock_path = os.path.join(sock_dir.name, 'hotplug.sock')
+
+ def _add_monitor(self):
+ """Create a chardev + monitor and return the socket path."""
+ sock = self._sock_path
+ self.vm.cmd('chardev-add', id='hotplug-chr', backend={
+ 'type': 'socket',
+ 'data': {
+ 'addr': {
+ 'type': 'unix',
+ 'data': {'path': sock}
+ },
+ 'server': True,
+ 'wait': False,
+ }
+ })
+ self.vm.cmd('object-add', id='hotplug-mon',
+ qom_type='monitor-qmp',
+ chardev='hotplug-chr')
+ return sock
+
+ def _remove_monitor(self):
+ """Remove the monitor + chardev."""
+ self.vm.cmd('object-del', id='hotplug-mon')
+ self.vm.cmd('chardev-remove', id='hotplug-chr')
+
+ def _connect_and_handshake(self, sock_path):
+ """
+ Connect to the dynamic monitor socket, perform the QMP
+ greeting and capability negotiation, send a command, then
+ disconnect.
+ """
+ qmp = QEMUMonitorProtocol(sock_path)
+
+ # connect(negotiate=True) receives the greeting, validates it,
+ # and sends qmp_capabilities automatically.
+ greeting = qmp.connect(negotiate=True)
+ self.assertIn('QMP', greeting)
+ self.assertIn('version', greeting['QMP'])
+ self.assertIn('capabilities', greeting['QMP'])
+
+ # Send a real command to prove the session is fully functional
+ resp = qmp.cmd_obj({'execute': 'query-version'})
+ self.assertIn('return', resp)
+ self.assertIn('qemu', resp['return'])
+
+ qmp.close()
+
+ def test_hotplug_cycle(self):
+ """
+ Hotplug a monitor, do the full QMP handshake, unplug it,
+ then repeat the whole cycle a second time.
+ """
+ self.set_machine('none')
+ self.vm.add_args('-nodefaults')
+ self.vm.launch()
+
+ # First cycle
+ sock = self._add_monitor()
+ self._connect_and_handshake(sock)
+ self._remove_monitor()
+
+ # Second cycle -- same ids, same path, must work
+ sock = self._add_monitor()
+ self._connect_and_handshake(sock)
+ self._remove_monitor()
+
+ def test_self_removal(self):
+ """
+ A dynamically-added monitor sends object-del targeting
+ itself. Verify the request is rejected, but the monitor
+ can still be deleted from outside its own context.
+ """
+ self.set_machine('none')
+ self.vm.add_args('-nodefaults')
+ self.vm.launch()
+
+ sock = self._add_monitor()
+
+ qmp = QEMUMonitorProtocol(sock)
+ greeting = qmp.connect(negotiate=True)
+ self.assertIn('QMP', greeting)
+
+ # Self-removal: the dynamic monitor raises error
+ resp = qmp.cmd_obj({'execute': 'object-del',
+ 'arguments': {'id': 'hotplug-mon'}})
+ self.assertIn('error', resp)
+
+ qmp.close()
+
+ resp = self.vm.cmd('object-del', id='hotplug-mon')
+
+ # Clean up the chardev
+ self.vm.cmd('chardev-remove', id='hotplug-chr')
+
+ def test_large_response(self):
+ """
+ Send a command with a large response (query-qmp-schema) on a
+ dynamically-added monitor to exercise the output buffer flush
+ path.
+ """
+ self.set_machine('none')
+ self.vm.add_args('-nodefaults')
+ self.vm.launch()
+
+ sock = self._add_monitor()
+
+ qmp = QEMUMonitorProtocol(sock)
+ qmp.connect(negotiate=True)
+
+ resp = qmp.cmd_obj({'execute': 'query-qmp-schema'})
+ self.assertIn('return', resp)
+ self.assertIsInstance(resp['return'], list)
+ self.assertGreater(len(resp['return']), 0)
+
+ qmp.close()
+ self._remove_monitor()
+
+ def test_events_after_negotiation(self):
+ """
+ Verify that QMP events are delivered on a dynamically-added
+ monitor after capability negotiation completes.
+ """
+ self.set_machine('none')
+ self.vm.add_args('-nodefaults')
+ self.vm.launch()
+
+ sock = self._add_monitor()
+
+ qmp = QEMUMonitorProtocol(sock)
+ qmp.connect(negotiate=True)
+
+ # Trigger a STOP event via the main monitor, then read it
+ # from the dynamic monitor.
+ self.vm.cmd('stop')
+ resp = qmp.pull_event(wait=True)
+ self.assertEqual(resp['event'], 'STOP')
+
+ self.vm.cmd('cont')
+ resp = qmp.pull_event(wait=True)
+ self.assertEqual(resp['event'], 'RESUME')
+
+ qmp.close()
+ self._remove_monitor()
+
+
+if __name__ == '__main__':
+ QemuSystemTest.main()
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 29/35] tests/functional: add a stress test for monitor hot unplug
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (27 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 28/35] tests/functional: add e2e test for dynamic QMP monitor hotplug Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 11:54 ` marcandre.lureau
2026-06-18 10:58 ` [PATCH v3 30/35] qom: add method for getting the "id" of a QOM object Daniel P. Berrangé
` (5 subsequent siblings)
34 siblings, 1 reply; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
When unplugging a monitor there is a careful synchronization dance
between the monitor handling the "object-del" command and the
command processing for the monitor being deleted.
The stress test runs a busy loop of 'query-qmp-schema' on a second
monitor, while the primary monitor requests its deletion.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
.../generic/test_monitor_hotplug.py | 62 +++++++++++++++++++
1 file changed, 62 insertions(+)
diff --git a/tests/functional/generic/test_monitor_hotplug.py b/tests/functional/generic/test_monitor_hotplug.py
index 5d8a159eb0..55af8a238f 100755
--- a/tests/functional/generic/test_monitor_hotplug.py
+++ b/tests/functional/generic/test_monitor_hotplug.py
@@ -6,11 +6,16 @@
#
# Copyright (c) 2026 Christian Brauner
+import asyncio
import os
+import random
+import threading
+import time
from qemu_test import QemuSystemTest
from qemu.qmp.legacy import QEMUMonitorProtocol
+from qemu.qmp import QMPClient
class MonitorHotplug(QemuSystemTest):
@@ -163,6 +168,63 @@ def test_events_after_negotiation(self):
qmp.close()
self._remove_monitor()
+ def stress_mon(self, sock):
+ async def main():
+ qmp = QMPClient('testvm')
+ await qmp.connect(sock)
+ # Run query-version in a tight loop so that the
+ # monitor thread/dispatcher is very busy at the
+ # time we try to delete the monitor
+ while True:
+ try:
+ # A command which returns a lot of data to make
+ # it more likely we're in the I/O reply path
+ # when deleting the monitor
+ res = await qmp.execute('query-qmp-schema')
+ # Some commands which generate async events
+ # as those can trigger different code paths
+ res = await qmp.execute('stop')
+ res = await qmp.execute('cont')
+ except:
+ # we'll get here if the monitor is terminated
+ # by QEMU in which case we must disconnect
+ # out side, but....
+ try:
+ await qmp.disconnect()
+ except (ConnectionResetError, EOFError, BrokenPipeError):
+ # ... disconnect() will probably see
+ # errors too, but we must try to call it
+ # regardless to cleanup asyncio state
+ # and prevent python warnings at GC time
+ pass
+ return
+ asyncio.run(main())
+
+ def test_hotplug_stress(self):
+ """
+ Repeatedly hotplug and unplug a monitor, while another thread
+ concurrently issues commands on that monitor. This stresses
+ the synchronization with the monitor thread during cleanup
+ """
+ self.set_machine('none')
+ self.vm.add_args('-nodefaults')
+ self.vm.launch()
+
+ # Each loop sleeps at most 0.5 seconds, so this should
+ # give an upper bound of approx 5 seconds execution
+ # time which is reasonable to run by default
+ repeat = 10
+ for i in range(repeat):
+ # First cycle
+ sock = self._add_monitor()
+ print ("# stress cycle %02d/%02d" % (i, repeat))
+ stress = threading.Thread(target=self.stress_mon, args=[sock])
+ stress.start()
+ # Sleep upto 1/2 second to vary the races
+ time.sleep(random.random() / 2)
+ self._remove_monitor()
+ stress.join()
+
if __name__ == '__main__':
QemuSystemTest.main()
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* Re: [PATCH v3 29/35] tests/functional: add a stress test for monitor hot unplug
2026-06-18 10:58 ` [PATCH v3 29/35] tests/functional: add a stress test for monitor hot unplug Daniel P. Berrangé
@ 2026-06-18 11:54 ` marcandre.lureau
0 siblings, 0 replies; 43+ messages in thread
From: marcandre.lureau @ 2026-06-18 11:54 UTC (permalink / raw)
To: Daniel P. Berrangé
Cc: qemu-devel, devel, Alex Bennée, Christian Brauner,
Markus Armbruster, Marc-André Lureau, Dr. David Alan Gilbert,
Paolo Bonzini, Philippe Mathieu-Daudé
On Thu, 18 Jun 2026 11:58:30 +0100, Daniel P. Berrangé <berrange@redhat.com> wrote:
> When unplugging a monitor there is a careful synchronization dance
> between the monitor handling the "object-del" command and the
> command processing for the monitor being deleted.
>
> The stress test runs a busy loop of 'query-qmp-schema' on a second
> monitor, while the primary monitor requests its deletion.
>
> [...]
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
--
Marc-André Lureau <marcandre.lureau@redhat.com>
^ permalink raw reply [flat|nested] 43+ messages in thread
* [PATCH v3 30/35] qom: add method for getting the "id" of a QOM object
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (28 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 29/35] tests/functional: add a stress test for monitor hot unplug Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 11:54 ` marcandre.lureau
2026-06-18 10:58 ` [PATCH v3 31/35] qom: add trace events for user creatable create/delete APIs Daniel P. Berrangé
` (4 subsequent siblings)
34 siblings, 1 reply; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
The 'user_creatable_del' method doesn't want the 'Object *', but
instead the "id" of the object to be deleted. While most of its
work could be done with the "Object *" alone, purging the QemuOpts
values needs the "id".
The "id" is not recorded against an Object though, it is indirectly
stored as a property linking the parent and child objects together.
Add an accessor that can fetch this property name.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
include/qom/object.h | 10 ++++++++++
qom/object.c | 17 +++++++++++++++++
2 files changed, 27 insertions(+)
diff --git a/include/qom/object.h b/include/qom/object.h
index 11f55613fc..216d2a30f6 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -1759,6 +1759,16 @@ ObjectProperty *object_property_try_add_child(Object *obj, const char *name,
ObjectProperty *object_property_add_child(Object *obj, const char *name,
Object *child);
+/**
+ * object_property_get_child_name:
+ * @obj: the object that owns the property
+ * @child: the object referenced by the child property
+ *
+ * Return the property name against which @child is registered
+ * with @obj, or NULL if @obj is not a parent of @child.
+ */
+char *object_property_get_child_name(Object *obj, Object *child);
+
typedef enum {
/* Unref the link pointer when the property is deleted */
OBJ_PROP_LINK_STRONG = 0x1,
diff --git a/qom/object.c b/qom/object.c
index 0ac201de4c..956adfb050 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -1964,6 +1964,23 @@ object_property_add_child(Object *obj, const char *name,
return object_property_try_add_child(obj, name, child, &error_abort);
}
+char *object_property_get_child_name(Object *obj, Object *child)
+{
+ ObjectProperty *prop;
+ GHashTableIter iter;
+ gpointer key, value;
+
+ g_hash_table_iter_init(&iter, obj->properties);
+ while (g_hash_table_iter_next(&iter, &key, &value)) {
+ prop = value;
+ if (object_property_is_child(prop) && prop->opaque == child) {
+ return g_strdup(prop->name);
+ }
+ }
+ return NULL;
+}
+
+
void object_property_allow_set_link(const Object *obj, const char *name,
Object *val, Error **errp)
{
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* Re: [PATCH v3 30/35] qom: add method for getting the "id" of a QOM object
2026-06-18 10:58 ` [PATCH v3 30/35] qom: add method for getting the "id" of a QOM object Daniel P. Berrangé
@ 2026-06-18 11:54 ` marcandre.lureau
0 siblings, 0 replies; 43+ messages in thread
From: marcandre.lureau @ 2026-06-18 11:54 UTC (permalink / raw)
To: Daniel P. Berrangé
Cc: qemu-devel, devel, Alex Bennée, Christian Brauner,
Markus Armbruster, Marc-André Lureau, Dr. David Alan Gilbert,
Paolo Bonzini, Philippe Mathieu-Daudé
On Thu, 18 Jun 2026 11:58:31 +0100, Daniel P. Berrangé <berrange@redhat.com> wrote:
> The 'user_creatable_del' method doesn't want the 'Object *', but
> instead the "id" of the object to be deleted. While most of its
> work could be done with the "Object *" alone, purging the QemuOpts
> values needs the "id".
>
> The "id" is not recorded against an Object though, it is indirectly
> stored as a property linking the parent and child objects together.
> Add an accessor that can fetch this property name.
>
> [...]
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
--
Marc-André Lureau <marcandre.lureau@redhat.com>
^ permalink raw reply [flat|nested] 43+ messages in thread
* [PATCH v3 31/35] qom: add trace events for user creatable create/delete APIs
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (29 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 30/35] qom: add method for getting the "id" of a QOM object Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 32/35] monitor: add support for auto-deleting monitors upon close Daniel P. Berrangé
` (3 subsequent siblings)
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
qom/object_interfaces.c | 6 ++++++
qom/trace-events | 5 +++++
2 files changed, 11 insertions(+)
diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c
index 6faa0b2fd9..2e618a7623 100644
--- a/qom/object_interfaces.c
+++ b/qom/object_interfaces.c
@@ -20,12 +20,14 @@
#include "qapi/opts-visitor.h"
#include "qemu/config-file.h"
#include "qemu/keyval.h"
+#include "trace.h"
bool user_creatable_complete(UserCreatable *uc, Error **errp)
{
UserCreatableClass *ucc = USER_CREATABLE_GET_CLASS(uc);
ERRP_GUARD();
+ trace_user_creatable_complete(uc, object_get_typename(OBJECT(uc)));
if (ucc->complete) {
ucc->complete(uc, errp);
}
@@ -37,9 +39,13 @@ bool user_creatable_prepare_delete(UserCreatable *uc, Error **errp)
UserCreatableClass *ucc = USER_CREATABLE_GET_CLASS(uc);
ERRP_GUARD();
+ trace_user_creatable_prepare_delete(uc, object_get_typename(OBJECT(uc)));
if (ucc->prepare_delete) {
ucc->prepare_delete(uc, errp);
}
+ trace_user_creatable_prepare_delete_result(
+ uc, object_get_typename(OBJECT(uc)),
+ *errp ? error_get_pretty(*errp) : NULL);
return !*errp;
}
diff --git a/qom/trace-events b/qom/trace-events
index 44c63e72af..bac8472618 100644
--- a/qom/trace-events
+++ b/qom/trace-events
@@ -11,3 +11,8 @@ object_property_del_child(void *obj, const char *type, void *child, const char *
object_property_parse(void *obj, const char *type, const char *name, const char *value) "obj=%p type=%s prop=%s value=%s"
object_class_dynamic_cast_assert(const char *type, const char *target, const char *file, int line, const char *func) "type=%s->%s (%s:%d:%s)"
object_class_property_add(const char *type, const char *name, void *value) "type=%s name=%s value=%p"
+
+# object_interfaces.c
+user_creatable_complete(void *obj, const char *type) "obj=%p type=%s"
+user_creatable_prepare_delete(void *obj, const char *type) "obj=%p type=%s"
+user_creatable_prepare_delete_result(void *obj, const char *type, const char *msg) "obj=%p type=%s msg=%s"
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 32/35] monitor: add support for auto-deleting monitors upon close
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (30 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 31/35] qom: add trace events for user creatable create/delete APIs Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 11:54 ` marcandre.lureau
2026-06-18 10:58 ` [PATCH v3 33/35] tests: switch from -mon to -object monitor-qmp Daniel P. Berrangé
` (2 subsequent siblings)
34 siblings, 1 reply; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
The default monitor is usually a long lived object that will exist for
the entire lifetime of the VM. A monitor can only service a single
client at a time though, and so it might be desirable to hotplug
additional monitors at runtime for specific tasks. If doing that,
however, there is a need to remove the monitor when it is no longer
needed.
Allowing a client to run "object-del" against its own monitor adds
complex edge cases, as it would be desirable to send the QMP response
despite the monitor sending it being deleted. Doing "object-del" alone
will also result in orphaning a character device backend instance, as
there is no opportunity to run the companion "chardev-del" command.
A simpler way to ensure cleanup is to add the concept of auto-deleting
monitor objects. Specifically when the "CHR_EVENT_CLOSED" event is
emitted, the equivalent of "object-del" + "chardev-del" can be run
internally. Since the transient client has already droppped its
monitor connection, there is no synchronization to be concerned about.
This is implemented via a new "close-action=none|delete" property on
the 'monitor-qmp' object. This concept could be extended with further
actions in future, for example:
* close-action=shutdown - graceful guest shutdown
* close-action=terminate - immediate guest poweroff
* close-action=stop - pause guest CPUs while the monitor is not
connected to any client
This is left as an exercise for future interested contributors.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
monitor/monitor-internal.h | 3 +
monitor/qmp.c | 59 +++++++++++++++++++
qapi/qom.json | 21 ++++++-
.../generic/test_monitor_hotplug.py | 55 +++++++++++++++--
4 files changed, 133 insertions(+), 5 deletions(-)
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index 5522e05464..23829f32f9 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -28,6 +28,7 @@
#include "chardev/char-fe.h"
#include "monitor/monitor.h"
#include "qapi/qapi-types-control.h"
+#include "qapi/qapi-types-qom.h"
#include "qapi/qmp-registry.h"
#include "qobject/json-parser.h"
#include "qemu/readline.h"
@@ -178,7 +179,9 @@ struct MonitorQMP {
Monitor parent_obj;
JSONMessageParser parser;
bool pretty;
+ MonitorQMPCloseAction close_action;
bool setup_pending; /* iothread BH has not yet set up chardev handlers */
+ bool delete_pending; /* close_action has started 'delete' process */
/*
* When a client connects, we're in capabilities negotiation mode.
* @commands is &qmp_cap_negotiation_commands then. When command
diff --git a/monitor/qmp.c b/monitor/qmp.c
index 5301927f09..7257edc19d 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -28,6 +28,7 @@
#include "monitor-internal.h"
#include "qapi/error.h"
#include "qapi/qapi-commands-control.h"
+#include "qapi/qapi-commands-char.h"
#include "qobject/qdict.h"
#include "qobject/qjson.h"
#include "qobject/qlist.h"
@@ -103,6 +104,20 @@ static void monitor_qmp_set_pretty(Object *obj, bool val, Error **errp)
mon->pretty = val;
}
+static int monitor_qmp_get_close_action(Object *obj, Error **errp)
+{
+ MonitorQMP *mon = MONITOR_QMP(obj);
+
+ return mon->close_action;
+}
+
+static void monitor_qmp_set_close_action(Object *obj, int val, Error **errp)
+{
+ MonitorQMP *mon = MONITOR_QMP(obj);
+
+ mon->close_action = val;
+}
+
static void monitor_qmp_emit_event(Monitor *mon, QAPIEvent event, QDict *qdict);
static bool monitor_qmp_requires_iothread(const Monitor *mon);
static void monitor_qmp_complete(UserCreatable *uc, Error **errp);
@@ -117,6 +132,11 @@ static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
object_class_property_add_bool(cls, "pretty",
monitor_qmp_get_pretty,
monitor_qmp_set_pretty);
+ object_class_property_add_enum(cls, "close-action",
+ "MonitorQMPCloseAction",
+ &MonitorQMPCloseAction_lookup,
+ monitor_qmp_get_close_action,
+ monitor_qmp_set_close_action);
moncls->emit_event = monitor_qmp_emit_event;
moncls->requires_iothread = monitor_qmp_requires_iothread;
@@ -550,11 +570,33 @@ static QDict *qmp_greeting(MonitorQMP *mon)
ver, cap_list);
}
+static void monitor_qmp_self_delete_bh(void *opaque)
+{
+ MonitorQMP *mon = opaque;
+ g_autofree char *mon_id = object_property_get_child_name(
+ object_get_objects_root(), OBJECT(mon));
+ g_autofree char *chardev_id = g_strdup(mon->parent_obj.chardev_id);
+ Error *local_error = NULL;
+
+ g_assert(mon_id);
+
+ user_creatable_del(mon_id, &local_error);
+ if (local_error != NULL) {
+ error_report_err(local_error);
+ } else {
+ qmp_chardev_remove(chardev_id, NULL);
+ }
+}
+
static void monitor_qmp_event(void *opaque, QEMUChrEvent event)
{
QDict *data;
MonitorQMP *mon = opaque;
+ if (mon->delete_pending) {
+ return;
+ }
+
switch (event) {
case CHR_EVENT_OPENED:
WITH_QEMU_LOCK_GUARD(&mon->parent_obj.mon_lock) {
@@ -577,6 +619,23 @@ static void monitor_qmp_event(void *opaque, QEMUChrEvent event)
json_message_parser_init(&mon->parser, handle_qmp_command,
mon, NULL);
monitor_fdsets_cleanup();
+ switch (mon->close_action) {
+ case MONITOR_QMP_CLOSE_ACTION_NONE:
+ break; /* nada */
+ case MONITOR_QMP_CLOSE_ACTION_DELETE:
+ mon->delete_pending = true;
+ /*
+ * Do NOT run in the AIO context associated with the
+ * monitor. We need to run in the default AIO context
+ * which is the same context in which 'qmp_object_del'
+ * will execute
+ */
+ aio_bh_schedule_oneshot(qemu_get_aio_context(),
+ monitor_qmp_self_delete_bh, mon);
+ break;
+ default:
+ g_assert_not_reached();
+ }
break;
case CHR_EVENT_BREAK:
case CHR_EVENT_MUX_IN:
diff --git a/qapi/qom.json b/qapi/qom.json
index 6ed510858e..63335b8fd0 100644
--- a/qapi/qom.json
+++ b/qapi/qom.json
@@ -1213,18 +1213,37 @@
'base': 'MonitorProperties',
'data': { '*readline': 'bool' } }
+
+##
+# @MonitorQMPCloseAction:
+#
+# Action to take when the character device backend is
+# closed.
+#
+# @none: take no action (the default)
+# @delete: delete both the 'monitor-qmp' object and its associated
+# character device backend object
+#
+# Since 11.1
+##
+{ 'enum' : 'MonitorQMPCloseAction',
+ 'data': ['none', 'delete'] }
+
##
# @MonitorQMPProperties:
#
# Properties for the QMP monitor
#
# @pretty: whether to pretty print JSON responses (default: disabled)
+# @close-action: action to take when the character device backend
+# is closed (default: none)
#
# Since: 11.1
##
{ 'struct': 'MonitorQMPProperties',
'base': 'MonitorProperties',
- 'data': { '*pretty': 'bool' } }
+ 'data': { '*pretty': 'bool',
+ '*close-action': 'MonitorQMPCloseAction' } }
##
# @ObjectType:
diff --git a/tests/functional/generic/test_monitor_hotplug.py b/tests/functional/generic/test_monitor_hotplug.py
index 55af8a238f..f70aed814f 100755
--- a/tests/functional/generic/test_monitor_hotplug.py
+++ b/tests/functional/generic/test_monitor_hotplug.py
@@ -25,7 +25,7 @@ def setUp(self):
sock_dir = self.socket_dir()
self._sock_path = os.path.join(sock_dir.name, 'hotplug.sock')
- def _add_monitor(self):
+ def _add_monitor(self, autodelete=False):
"""Create a chardev + monitor and return the socket path."""
sock = self._sock_path
self.vm.cmd('chardev-add', id='hotplug-chr', backend={
@@ -39,9 +39,15 @@ def _add_monitor(self):
'wait': False,
}
})
- self.vm.cmd('object-add', id='hotplug-mon',
- qom_type='monitor-qmp',
- chardev='hotplug-chr')
+ if autodelete:
+ self.vm.cmd('object-add', id='hotplug-mon',
+ qom_type='monitor-qmp',
+ chardev='hotplug-chr',
+ close_action='delete')
+ else:
+ self.vm.cmd('object-add', id='hotplug-mon',
+ qom_type='monitor-qmp',
+ chardev='hotplug-chr')
return sock
def _remove_monitor(self):
@@ -118,6 +124,47 @@ def test_self_removal(self):
# Clean up the chardev
self.vm.cmd('chardev-remove', id='hotplug-chr')
+ def test_auto_delete(self):
+ """
+ A dynamically-added monitor is configured with 'close-action=delete'
+ should see itself deleted when the client is closed.
+ """
+ self.set_machine('none')
+ self.vm.add_args('-nodefaults')
+ self.vm.launch()
+
+ sock = self._add_monitor(autodelete=True)
+
+ cdevs = [c["label"] for c in self.vm.cmd('query-chardev')]
+ objs = [o["name"] for o in self.vm.cmd('qom-list', path='/objects')]
+ assert ('hotplug-chr' in cdevs)
+ assert ('hotplug-mon' in objs)
+
+ qmp = QEMUMonitorProtocol(sock)
+ greeting = qmp.connect(negotiate=True)
+ self.assertIn('QMP', greeting)
+
+ cdevs = [c["label"] for c in self.vm.cmd('query-chardev')]
+ objs = [o["name"] for o in self.vm.cmd('qom-list', path='/objects')]
+ assert ('hotplug-chr' in cdevs)
+ assert ('hotplug-mon' in objs)
+
+ qmp.close()
+
+ # Wait upto 10 seconds max for chardev to auto-delete, which
+ # is hopefully enough for reliability under high load
+ for i in range(int(10 / 0.2)):
+ cdevs = [c["label"] for c in self.vm.cmd('query-chardev')]
+ if 'hotplug-chr' not in cdevs:
+ break
+ # Wait a little more then try again
+ time.sleep(0.2)
+
+ cdevs = [c["label"] for c in self.vm.cmd('query-chardev')]
+ objs = [o["name"] for o in self.vm.cmd('qom-list', path='/objects')]
+ assert ('hotplug-chr' not in cdevs)
+ assert ('hotplug-mon' not in objs)
+
def test_large_response(self):
"""
Send a command with a large response (query-qmp-schema) on a
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* Re: [PATCH v3 32/35] monitor: add support for auto-deleting monitors upon close
2026-06-18 10:58 ` [PATCH v3 32/35] monitor: add support for auto-deleting monitors upon close Daniel P. Berrangé
@ 2026-06-18 11:54 ` marcandre.lureau
0 siblings, 0 replies; 43+ messages in thread
From: marcandre.lureau @ 2026-06-18 11:54 UTC (permalink / raw)
To: Daniel P. Berrangé
Cc: qemu-devel, devel, Alex Bennée, Christian Brauner,
Markus Armbruster, Marc-André Lureau, Dr. David Alan Gilbert,
Paolo Bonzini, Philippe Mathieu-Daudé
> The default monitor is usually a long lived object that will exist for
> the entire lifetime of the VM. A monitor can only service a single
> client at a time though, and so it might be desirable to hotplug
> additional monitors at runtime for specific tasks. If doing that,
> however, there is a need to remove the monitor when it is no longer
> needed.
>
> Allowing a client to run "object-del" against its own monitor adds
> complex edge cases, as it would be desirable to send the QMP response
> despite the monitor sending it being deleted. Doing "object-del" alone
> will also result in orphaning a character device backend instance, as
> there is no opportunity to run the companion "chardev-del" command.
>
> A simpler way to ensure cleanup is to add the concept of auto-deleting
> monitor objects. Specifically when the "CHR_EVENT_CLOSED" event is
> emitted, the equivalent of "object-del" + "chardev-del" can be run
> internally. Since the transient client has already droppped its
> monitor connection, there is no synchronization to be concerned about.
>
> This is implemented via a new "close-action=none|delete" property on
> the 'monitor-qmp' object. This concept could be extended with further
> actions in future, for example:
>
> * close-action=shutdown - graceful guest shutdown
> * close-action=terminate - immediate guest poweroff
> * close-action=stop - pause guest CPUs while the monitor is not
> connected to any client
>
> This is left as an exercise for future interested contributors.
>
> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
> Message-ID: <20260618105836.991609-33-berrange@redhat.com>
>
> diff --git a/qapi/qom.json b/qapi/qom.json
> index 6ed510858e1..63335b8fd09 100644
> --- a/qapi/qom.json
> +++ b/qapi/qom.json
> @@ -1213,18 +1213,37 @@
> 'base': 'MonitorProperties',
> 'data': { '*readline': 'bool' } }
>
> +
> +##
> +# @MonitorQMPCloseAction:
> +#
> +# Action to take when the character device backend is
> +# closed.
> +#
> +# @none: take no action (the default)
> +# @delete: delete both the 'monitor-qmp' object and its associated
> +# character device backend object
> +#
> +# Since 11.1
> +##
> +{ 'enum' : 'MonitorQMPCloseAction',
> + 'data': ['none', 'delete'] }
> +
> ##
> # @MonitorQMPProperties:
> #
> # Properties for the QMP monitor
> #
> # @pretty: whether to pretty print JSON responses (default: disabled)
> +# @close-action: action to take when the character device backend
> +# is closed (default: none)
> #
> # Since: 11.1
> ##
> { 'struct': 'MonitorQMPProperties',
> 'base': 'MonitorProperties',
> - 'data': { '*pretty': 'bool' } }
> + 'data': { '*pretty': 'bool',
> + '*close-action': 'MonitorQMPCloseAction' } }
>
> ##
> # @ObjectType:
> diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
> index 5522e05464b..23829f32f9a 100644
> --- a/monitor/monitor-internal.h
> +++ b/monitor/monitor-internal.h
> @@ -28,6 +28,7 @@
> #include "chardev/char-fe.h"
> #include "monitor/monitor.h"
> #include "qapi/qapi-types-control.h"
> +#include "qapi/qapi-types-qom.h"
> #include "qapi/qmp-registry.h"
> #include "qobject/json-parser.h"
> #include "qemu/readline.h"
> @@ -178,7 +179,9 @@ struct MonitorQMP {
> Monitor parent_obj;
> JSONMessageParser parser;
> bool pretty;
> + MonitorQMPCloseAction close_action;
> bool setup_pending; /* iothread BH has not yet set up chardev handlers */
> + bool delete_pending; /* close_action has started 'delete' process */
> /*
> * When a client connects, we're in capabilities negotiation mode.
> * @commands is &qmp_cap_negotiation_commands then. When command
> diff --git a/monitor/qmp.c b/monitor/qmp.c
> index 5301927f09f..7257edc19d2 100644
> --- a/monitor/qmp.c
> +++ b/monitor/qmp.c
> @@ -28,6 +28,7 @@
> #include "monitor-internal.h"
> #include "qapi/error.h"
> #include "qapi/qapi-commands-control.h"
> +#include "qapi/qapi-commands-char.h"
> #include "qobject/qdict.h"
> #include "qobject/qjson.h"
> #include "qobject/qlist.h"
> @@ -103,6 +104,20 @@ static void monitor_qmp_set_pretty(Object *obj, bool val, Error **errp)
> mon->pretty = val;
> }
>
> +static int monitor_qmp_get_close_action(Object *obj, Error **errp)
> +{
> + MonitorQMP *mon = MONITOR_QMP(obj);
> +
> + return mon->close_action;
> +}
> +
> +static void monitor_qmp_set_close_action(Object *obj, int val, Error **errp)
> +{
> + MonitorQMP *mon = MONITOR_QMP(obj);
> +
> + mon->close_action = val;
> +}
> +
> static void monitor_qmp_emit_event(Monitor *mon, QAPIEvent event, QDict *qdict);
> static bool monitor_qmp_requires_iothread(const Monitor *mon);
> static void monitor_qmp_complete(UserCreatable *uc, Error **errp);
> @@ -117,6 +132,11 @@ static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
> object_class_property_add_bool(cls, "pretty",
> monitor_qmp_get_pretty,
> monitor_qmp_set_pretty);
> + object_class_property_add_enum(cls, "close-action",
> + "MonitorQMPCloseAction",
> + &MonitorQMPCloseAction_lookup,
> + monitor_qmp_get_close_action,
> + monitor_qmp_set_close_action);
>
> moncls->emit_event = monitor_qmp_emit_event;
> moncls->requires_iothread = monitor_qmp_requires_iothread;
> @@ -550,11 +570,33 @@ static QDict *qmp_greeting(MonitorQMP *mon)
> ver, cap_list);
> }
>
> +static void monitor_qmp_self_delete_bh(void *opaque)
> +{
> + MonitorQMP *mon = opaque;
There is a potential race if object-del is called on the same MonitorQMP before the BH fires.
> + g_autofree char *mon_id = object_property_get_child_name(
> + object_get_objects_root(), OBJECT(mon));
> + g_autofree char *chardev_id = g_strdup(mon->parent_obj.chardev_id);
> + Error *local_error = NULL;
> +
> + g_assert(mon_id);
> +
> + user_creatable_del(mon_id, &local_error);
> + if (local_error != NULL) {
> + error_report_err(local_error);
> + } else {
> + qmp_chardev_remove(chardev_id, NULL);
> + }
> +}
> +
> static void monitor_qmp_event(void *opaque, QEMUChrEvent event)
> {
> QDict *data;
> MonitorQMP *mon = opaque;
>
> + if (mon->delete_pending) {
> + return;
> + }
> +
> switch (event) {
> case CHR_EVENT_OPENED:
> WITH_QEMU_LOCK_GUARD(&mon->parent_obj.mon_lock) {
> @@ -577,6 +619,23 @@ static void monitor_qmp_event(void *opaque, QEMUChrEvent event)
> json_message_parser_init(&mon->parser, handle_qmp_command,
> mon, NULL);
> monitor_fdsets_cleanup();
> + switch (mon->close_action) {
> + case MONITOR_QMP_CLOSE_ACTION_NONE:
> + break; /* nada */
> + case MONITOR_QMP_CLOSE_ACTION_DELETE:
> + mon->delete_pending = true;
> + /*
> + * Do NOT run in the AIO context associated with the
> + * monitor. We need to run in the default AIO context
> + * which is the same context in which 'qmp_object_del'
> + * will execute
> + */
> + aio_bh_schedule_oneshot(qemu_get_aio_context(),
> + monitor_qmp_self_delete_bh, mon);
ref it?
--
Marc-André Lureau <marcandre.lureau@redhat.com>
^ permalink raw reply [flat|nested] 43+ messages in thread
* [PATCH v3 33/35] tests: switch from -mon to -object monitor-qmp
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (31 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 32/35] monitor: add support for auto-deleting monitors upon close Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 34/35] qemu-options: document new monitor-hmp and monitor-qmp objects Daniel P. Berrangé
2026-06-18 10:58 ` [PATCH v3 35/35] docs: mark '-mon' as deprecated in favour of -object Daniel P. Berrangé
34 siblings, 0 replies; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
Use the new preferred low level option for configuring the
QMP service in libqtest and the python Machine class used
by tests. This will avoid triggering deprecation warnings
after the subsequent commit.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
python/qemu/machine/machine.py | 4 ++--
tests/qtest/libqtest.c | 2 +-
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/python/qemu/machine/machine.py b/python/qemu/machine/machine.py
index ebb58d5b68..5f4845f5fb 100644
--- a/python/qemu/machine/machine.py
+++ b/python/qemu/machine/machine.py
@@ -304,8 +304,8 @@ def _base_args(self) -> List[str]:
)
else:
moncdev = f"socket,id=mon,path={self._monitor_address}"
- args.extend(['-chardev', moncdev, '-mon',
- 'chardev=mon,mode=control'])
+ args.extend(['-chardev', moncdev, '-object',
+ 'monitor-qmp,id=qmp,chardev=mon'])
if self._machine is not None:
args.extend(['-machine', self._machine])
diff --git a/tests/qtest/libqtest.c b/tests/qtest/libqtest.c
index 4e22c66b75..c33c799c92 100644
--- a/tests/qtest/libqtest.c
+++ b/tests/qtest/libqtest.c
@@ -460,7 +460,7 @@ gchar *qtest_qemu_args(const char *extra_args)
"-qtest unix:%s "
"-qtest-log %s "
"-chardev socket,path=%s,id=char0 "
- "-mon chardev=char0,mode=control "
+ "-object monitor-qmp,id=qmp0,chardev=char0 "
"-display none "
"-audio none "
"%s "
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* [PATCH v3 34/35] qemu-options: document new monitor-hmp and monitor-qmp objects
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (32 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 33/35] tests: switch from -mon to -object monitor-qmp Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 11:54 ` marcandre.lureau
2026-06-18 10:58 ` [PATCH v3 35/35] docs: mark '-mon' as deprecated in favour of -object Daniel P. Berrangé
34 siblings, 1 reply; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
Add new docs for the `-object monitor-hmp` and `-object monitor-qmp`
options, updating `-mon` to state that it is legacy syntax sugar
for the new `-object` args.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
qemu-options.hx | 50 +++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 50 insertions(+)
diff --git a/qemu-options.hx b/qemu-options.hx
index c799286153..98c74cc9ff 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -4980,6 +4980,16 @@ SRST
-mon chardev=mon1,mode=control,pretty=on
enables the QMP monitor on localhost port 4444 with pretty-printing.
+
+ The use of ``-mon mode=readline`` is historical syntax sugar
+ for the new ``-object monitor-hmp`` option, each use of which
+ creates an object with the ID ``hmpcompatNNN`` where ``NNN`` is
+ a counter starting from 0.
+
+ The use of ``-mon mode=control`` is historical syntax sugar
+ for the new ``-object monitor-qmp`` option, each use of which
+ creates an object with the ID ``qmpcompatNNN`` where ``NNN`` is
+ a counter starting from 0.
ERST
DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
@@ -5730,6 +5740,46 @@ SRST
they are specified. Note that the 'id' property must be set. These
objects are placed in the '/objects' path.
+ ``-object monitor-hmp,id=id,chardev=chardev_id,readline=on|off``
+ Set up a monitor running the Human Monitor Protocol,
+ connected to the chardev ``chardev_id``.
+
+ The ``id`` parameter is a unique ID that can be used
+ to dynamically delete the monitor at runtime. Note
+ that monitors created using the historical syntax
+ will be allocated IDs following the pattern ``hmpcompatNN``.
+ Mixing ``-object`` with the historical monitor syntax is
+ discouraged.
+
+ The ``readline`` parameter, which defaults to ``on``,
+ controls whether the monitor provides interactive
+ prompts
+
+ ``-object monitor-qmp,id=id,chardev=chardev_id,pretty=on|off,close-action=none|delete``
+ Set up a monitor running the QEMU Monitor Protocol,
+ connected to the chardev ``chardev_id``.
+
+ The ``id`` parameter is a unique ID that can be used
+ to dynamically delete the monitor at runtime. Note
+ that monitors created using the historical syntax
+ will be allocated IDs following the pattern ``qmpcompatNN``.
+ Mixing ``-object`` with the historical monitor syntax is
+ discouraged.
+
+ The ``pretty`` parameter, which defaults to ``off``,
+ controls whether the monitor responses are pretty
+ printed as multi-line indented JSON, as opposed to
+ constrained to a single line without extraneous
+ whitespace.
+
+ The ``close-action`` parameter, which defaults to ``none``,
+ controls what happens when the connection to the monitor
+ is terminated by the user. If set to ``delete``, then the
+ ``monitor-qmp`` object and its associated character
+ device are both immediately deleted. This can be useful
+ if an extra monitor was hotplugged for a specific task
+ and should be unplugged when completed.
+
``-object memory-backend-file,id=id,size=size,mem-path=dir,share=on|off,discard-data=on|off,merge=on|off,dump=on|off,prealloc=on|off,host-nodes=host-nodes,policy=default|preferred|bind|interleave,align=align,offset=offset,readonly=on|off,rom=on|off|auto``
Creates a memory file backend object, which can be used to back
the guest RAM with huge pages.
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* Re: [PATCH v3 34/35] qemu-options: document new monitor-hmp and monitor-qmp objects
2026-06-18 10:58 ` [PATCH v3 34/35] qemu-options: document new monitor-hmp and monitor-qmp objects Daniel P. Berrangé
@ 2026-06-18 11:54 ` marcandre.lureau
0 siblings, 0 replies; 43+ messages in thread
From: marcandre.lureau @ 2026-06-18 11:54 UTC (permalink / raw)
To: Daniel P. Berrangé
Cc: qemu-devel, devel, Alex Bennée, Christian Brauner,
Markus Armbruster, Marc-André Lureau, Dr. David Alan Gilbert,
Paolo Bonzini, Philippe Mathieu-Daudé
On Thu, 18 Jun 2026 11:58:35 +0100, Daniel P. Berrangé <berrange@redhat.com> wrote:
> Add new docs for the `-object monitor-hmp` and `-object monitor-qmp`
> options, updating `-mon` to state that it is legacy syntax sugar
> for the new `-object` args.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
--
Marc-André Lureau <marcandre.lureau@redhat.com>
^ permalink raw reply [flat|nested] 43+ messages in thread
* [PATCH v3 35/35] docs: mark '-mon' as deprecated in favour of -object
2026-06-18 10:58 [PATCH v3 00/35] monitor: turn QMP and HMP into QOM objects Daniel P. Berrangé
` (33 preceding siblings ...)
2026-06-18 10:58 ` [PATCH v3 34/35] qemu-options: document new monitor-hmp and monitor-qmp objects Daniel P. Berrangé
@ 2026-06-18 10:58 ` Daniel P. Berrangé
2026-06-18 11:54 ` marcandre.lureau
34 siblings, 1 reply; 43+ messages in thread
From: Daniel P. Berrangé @ 2026-06-18 10:58 UTC (permalink / raw)
To: qemu-devel
Cc: devel, Alex Bennée, Christian Brauner, Markus Armbruster,
Marc-André Lureau, Dr. David Alan Gilbert, Paolo Bonzini,
Philippe Mathieu-Daudé, Daniel P. Berrangé
The high level `-qmp` and `-monitor` options can remain as convenience
wrappers, but the low level `-mon` is completed obsoleted by the new
`-object` support with 'monitor-qmp' and 'monitor-hmp' types.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
docs/about/deprecated.rst | 10 ++++++++++
docs/devel/writing-monitor-commands.rst | 4 ++--
docs/system/arm/xenpvh.rst | 4 ++--
docs/system/i386/xen.rst | 3 ++-
docs/system/i386/xenpvh.rst | 4 ++--
qemu-options.hx | 11 ++++++-----
system/vl.c | 2 ++
7 files changed, 26 insertions(+), 12 deletions(-)
diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
index 97750f5edc..8370fc5680 100644
--- a/docs/about/deprecated.rst
+++ b/docs/about/deprecated.rst
@@ -61,6 +61,16 @@ The ``debug-threads`` option of the ``-name`` argument is now
ignored. Thread naming is unconditionally enabled for all platforms
where it is supported.
+``-mon`` option (since 11.1)
+''''''''''''''''''''''''''''
+
+The ``-mon`` option was the generic mechanism for creating monitor objects
+if the convenience ``-qmp`` or ``-monitor`` options were not flexible
+enough. The monitor objects have been converted to QOM, so ``-mon mode=readline``
+is replaced by ``-object monitor-hmp`` and ``-mon mode=control`` is replaced
+by ``-object monitor-qmp``. The short convenience options are not deprecated,
+only ``-mon``.
+
QEMU Machine Protocol (QMP) commands
------------------------------------
diff --git a/docs/devel/writing-monitor-commands.rst b/docs/devel/writing-monitor-commands.rst
index 930da5cd06..7ae7efe327 100644
--- a/docs/devel/writing-monitor-commands.rst
+++ b/docs/devel/writing-monitor-commands.rst
@@ -52,8 +52,8 @@ shown here.
First, QEMU should be started like this::
# qemu-system-TARGET [...] \
- -chardev socket,id=qmp,port=4444,host=localhost,server=on \
- -mon chardev=qmp,mode=control,pretty=on
+ -chardev socket,id=chrqmp0,port=4444,host=localhost,server=on \
+ -object monitor-qmp,chardev=chrqmp0,pretty=on,id=qmp0
Then, in a different terminal::
diff --git a/docs/system/arm/xenpvh.rst b/docs/system/arm/xenpvh.rst
index 430ac2c02e..511af63e3d 100644
--- a/docs/system/arm/xenpvh.rst
+++ b/docs/system/arm/xenpvh.rst
@@ -27,9 +27,9 @@ Sample QEMU xenpvh commands for running and connecting with Xen:
qemu-system-aarch64 -xen-domid 1 \
-chardev socket,id=libxl-cmd,path=qmp-libxl-1,server=on,wait=off \
- -mon chardev=libxl-cmd,mode=control \
+ -object monitor-qmp,id=qmp0,chardev=libxl-cmd \
-chardev socket,id=libxenstat-cmd,path=qmp-libxenstat-1,server=on,wait=off \
- -mon chardev=libxenstat-cmd,mode=control \
+ -object monitor-qmp,id=qmp1,chardev=libxenstat-cmd \
-xen-attach -name guest0 -vnc none -display none -nographic \
-machine xenpvh -m 1301 \
-chardev socket,id=chrtpm,path=tmp/vtpm2/swtpm-sock \
diff --git a/docs/system/i386/xen.rst b/docs/system/i386/xen.rst
index 46db5f34c1..6ff5cdb1e4 100644
--- a/docs/system/i386/xen.rst
+++ b/docs/system/i386/xen.rst
@@ -79,7 +79,8 @@ of type ``xen-console`` to connect to it. For the Xen console equivalent of
the handy ``-serial mon:stdio`` option, for example:
.. parsed-literal::
- -chardev stdio,mux=on,id=char0,signal=off -mon char0 \\
+ -chardev stdio,mux=on,id=char0,signal=off \\
+ -object monitor-hmp,chardev=char0,id=hmp0 \\
-device xen-console,chardev=char0
The Xen network device is ``xen-net-device``, which becomes the default NIC
diff --git a/docs/system/i386/xenpvh.rst b/docs/system/i386/xenpvh.rst
index 354250f073..904778e3f5 100644
--- a/docs/system/i386/xenpvh.rst
+++ b/docs/system/i386/xenpvh.rst
@@ -33,9 +33,9 @@ case you need to construct one manually:
qemu-system-i386 -xen-domid 3 -no-shutdown \
-chardev socket,id=libxl-cmd,path=/var/run/xen/qmp-libxl-3,server=on,wait=off \
- -mon chardev=libxl-cmd,mode=control \
+ -object monitor-qmp,id=qmp0,chardev=libxl-cmd \
-chardev socket,id=libxenstat-cmd,path=/var/run/xen/qmp-libxenstat-3,server=on,wait=off \
- -mon chardev=libxenstat-cmd,mode=control \
+ -object monitor-qmp,id=qmp1,chardev=libxenstat-cmd \
-nodefaults \
-no-user-config \
-xen-attach -name g0 \
diff --git a/qemu-options.hx b/qemu-options.hx
index 98c74cc9ff..32b0cfba03 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -4137,7 +4137,7 @@ The general form of a character device option is:
::
-chardev stdio,mux=on,id=char0 \
- -mon chardev=char0,mode=readline \
+ -object monitor-hmp,id=hmp0,chardev=char0 \
-serial chardev:char0 \
-serial chardev:char0
@@ -4149,7 +4149,7 @@ The general form of a character device option is:
::
-chardev stdio,mux=on,id=char0 \
- -mon chardev=char0,mode=readline \
+ -object monitor-hmp,id=hmp0,chardev=char0 \
-parallel chardev:char0 \
-chardev tcp,...,mux=on,id=char1 \
-serial chardev:char1 \
@@ -4950,7 +4950,8 @@ SRST
-qmp tcp:localhost:4444,server=on,wait=off
Not all options are configurable via this syntax; for maximum
- flexibility use the ``-mon`` option and an accompanying ``-chardev``.
+ flexibility use ``-object monitor-qmp`` and an accompanying
+ ``-chardev``.
ERST
DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \
@@ -4981,12 +4982,12 @@ SRST
enables the QMP monitor on localhost port 4444 with pretty-printing.
- The use of ``-mon mode=readline`` is historical syntax sugar
+ The use of ``-mon mode=readline`` is deprecated syntax sugar
for the new ``-object monitor-hmp`` option, each use of which
creates an object with the ID ``hmpcompatNNN`` where ``NNN`` is
a counter starting from 0.
- The use of ``-mon mode=control`` is historical syntax sugar
+ The use of ``-mon mode=control`` is deprecated syntax sugar
for the new ``-object monitor-qmp`` option, each use of which
creates an object with the ID ``qmpcompatNNN`` where ``NNN`` is
a counter starting from 0.
diff --git a/system/vl.c b/system/vl.c
index 86f09a8b5c..9a71eb409a 100644
--- a/system/vl.c
+++ b/system/vl.c
@@ -3239,6 +3239,8 @@ void qemu_init(int argc, char **argv)
default_monitor = 0;
break;
case QEMU_OPTION_mon:
+ warn_report_once("'-mon' is deprecated, use '-object' with "
+ "'monitor-hmp' or 'monitor-qmp' types instead");
if (!qemu_opts_parse_noisily(qemu_find_opts("mon"), optarg,
true)) {
exit(1);
--
2.54.0
^ permalink raw reply related [flat|nested] 43+ messages in thread* Re: [PATCH v3 35/35] docs: mark '-mon' as deprecated in favour of -object
2026-06-18 10:58 ` [PATCH v3 35/35] docs: mark '-mon' as deprecated in favour of -object Daniel P. Berrangé
@ 2026-06-18 11:54 ` marcandre.lureau
0 siblings, 0 replies; 43+ messages in thread
From: marcandre.lureau @ 2026-06-18 11:54 UTC (permalink / raw)
To: Daniel P. Berrangé
Cc: qemu-devel, devel, Alex Bennée, Christian Brauner,
Markus Armbruster, Marc-André Lureau, Dr. David Alan Gilbert,
Paolo Bonzini, Philippe Mathieu-Daudé
On Thu, 18 Jun 2026 11:58:36 +0100, Daniel P. Berrangé <berrange@redhat.com> wrote:
> The high level `-qmp` and `-monitor` options can remain as convenience
> wrappers, but the low level `-mon` is completed obsoleted by the new
> `-object` support with 'monitor-qmp' and 'monitor-hmp' types.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
--
Marc-André Lureau <marcandre.lureau@redhat.com>
^ permalink raw reply [flat|nested] 43+ messages in thread