* [PATCH v3 1/7] xen/xsm: make getdomaininfo xsm dummy checks more stringent
2024-12-13 16:24 [PATCH v3 0/7] remove libxenctrl usage from xenstored Juergen Gross
@ 2024-12-13 16:24 ` Juergen Gross
2024-12-13 16:24 ` [PATCH v3 2/7] tools: add a dedicated header file for barrier definitions Juergen Gross
` (5 subsequent siblings)
6 siblings, 0 replies; 18+ messages in thread
From: Juergen Gross @ 2024-12-13 16:24 UTC (permalink / raw)
To: xen-devel
Cc: Juergen Gross, Andrew Cooper, Anthony PERARD, Michal Orzel,
Jan Beulich, Julien Grall, Roger Pau Monné,
Stefano Stabellini, Daniel P. Smith
Today the dummy XSM privilege checks for getdomaininfo are less
stringent than possible: they basically rely on the general
sysctl/domctl entry check to do all tests and then do the test with
the XSM_HOOK privilege, which is an "allow all" default.
Instead of XSM_HOOK use XSM_XS_PRIV, which is the privilege really
wanted. Note that this test is still wider than the sysctl entry test,
but there is no easy way to make both domctl and sysctl happy at the
same time.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
---
V2:
- new patch
---
xen/common/domctl.c | 2 +-
xen/common/sysctl.c | 2 +-
xen/include/xsm/dummy.h | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/xen/common/domctl.c b/xen/common/domctl.c
index ea16b75910..444e072fdc 100644
--- a/xen/common/domctl.c
+++ b/xen/common/domctl.c
@@ -539,7 +539,7 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) u_domctl)
break;
case XEN_DOMCTL_getdomaininfo:
- ret = xsm_getdomaininfo(XSM_HOOK, d);
+ ret = xsm_getdomaininfo(XSM_XS_PRIV, d);
if ( ret )
break;
diff --git a/xen/common/sysctl.c b/xen/common/sysctl.c
index d02f44fe3a..c2d99ae12e 100644
--- a/xen/common/sysctl.c
+++ b/xen/common/sysctl.c
@@ -89,7 +89,7 @@ long do_sysctl(XEN_GUEST_HANDLE_PARAM(xen_sysctl_t) u_sysctl)
if ( num_domains == op->u.getdomaininfolist.max_domains )
break;
- if ( xsm_getdomaininfo(XSM_HOOK, d) )
+ if ( xsm_getdomaininfo(XSM_XS_PRIV, d) )
continue;
getdomaininfo(d, &info);
diff --git a/xen/include/xsm/dummy.h b/xen/include/xsm/dummy.h
index 7956f27a29..f8a3c4b81e 100644
--- a/xen/include/xsm/dummy.h
+++ b/xen/include/xsm/dummy.h
@@ -137,7 +137,7 @@ static XSM_INLINE int cf_check xsm_domain_create(
static XSM_INLINE int cf_check xsm_getdomaininfo(
XSM_DEFAULT_ARG struct domain *d)
{
- XSM_ASSERT_ACTION(XSM_HOOK);
+ XSM_ASSERT_ACTION(XSM_XS_PRIV);
return xsm_default_action(action, current->domain, d);
}
--
2.43.0
^ permalink raw reply related [flat|nested] 18+ messages in thread* [PATCH v3 2/7] tools: add a dedicated header file for barrier definitions
2024-12-13 16:24 [PATCH v3 0/7] remove libxenctrl usage from xenstored Juergen Gross
2024-12-13 16:24 ` [PATCH v3 1/7] xen/xsm: make getdomaininfo xsm dummy checks more stringent Juergen Gross
@ 2024-12-13 16:24 ` Juergen Gross
2024-12-16 14:14 ` Anthony PERARD
2024-12-13 16:24 ` [PATCH v3 3/7] xen: add a domain unique id to each domain Juergen Gross
` (4 subsequent siblings)
6 siblings, 1 reply; 18+ messages in thread
From: Juergen Gross @ 2024-12-13 16:24 UTC (permalink / raw)
To: xen-devel; +Cc: Juergen Gross, Anthony PERARD
Instead of having to include xenctrl.h for getting definitions of cpu
barriers, add a dedicated header for that purpose.
Switch the xen-9pfsd daemon to use the new header instead of xenctrl.h.
This is in preparation of making Xenstore independent from libxenctrl.
Signed-off-by: Juergen Gross <jgross@suse.com>
---
V1:
- new patch
V2:
- use SPDX
- modify guard define (Anthony PERARD)
- moved earlier in the series
---
tools/9pfsd/io.c | 5 ++++-
tools/include/xen-barrier.h | 39 +++++++++++++++++++++++++++++++++++++
tools/include/xenctrl.h | 28 +-------------------------
tools/libs/ctrl/Makefile | 2 +-
4 files changed, 45 insertions(+), 29 deletions(-)
create mode 100644 tools/include/xen-barrier.h
diff --git a/tools/9pfsd/io.c b/tools/9pfsd/io.c
index 468e0241f5..14cfcaf568 100644
--- a/tools/9pfsd/io.c
+++ b/tools/9pfsd/io.c
@@ -13,15 +13,18 @@
#include <assert.h>
#include <errno.h>
+#include <stdarg.h>
#include <stdbool.h>
+#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
+#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include <fcntl.h>
-#include <xenctrl.h> /* For cpu barriers. */
+#include <xen-barrier.h>
#include <xen-tools/common-macros.h>
#include "xen-9pfsd.h"
diff --git a/tools/include/xen-barrier.h b/tools/include/xen-barrier.h
new file mode 100644
index 0000000000..a716fb93cc
--- /dev/null
+++ b/tools/include/xen-barrier.h
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
+/******************************************************************************
+ * xen-barrier.h
+ *
+ * Definition of CPU barriers, part of libxenctrl.
+ *
+ * Copyright (c) 2003-2004, K A Fraser.
+ */
+
+#ifndef XEN_BARRIER_H
+#define XEN_BARRIER_H
+
+/*
+ * DEFINITIONS FOR CPU BARRIERS
+ */
+
+#define xen_barrier() asm volatile ( "" : : : "memory")
+
+#if defined(__i386__)
+#define xen_mb() asm volatile ( "lock addl $0, -4(%%esp)" ::: "memory" )
+#define xen_rmb() xen_barrier()
+#define xen_wmb() xen_barrier()
+#elif defined(__x86_64__)
+#define xen_mb() asm volatile ( "lock addl $0, -32(%%rsp)" ::: "memory" )
+#define xen_rmb() xen_barrier()
+#define xen_wmb() xen_barrier()
+#elif defined(__arm__)
+#define xen_mb() asm volatile ("dmb" : : : "memory")
+#define xen_rmb() asm volatile ("dmb" : : : "memory")
+#define xen_wmb() asm volatile ("dmb" : : : "memory")
+#elif defined(__aarch64__)
+#define xen_mb() asm volatile ("dmb sy" : : : "memory")
+#define xen_rmb() asm volatile ("dmb sy" : : : "memory")
+#define xen_wmb() asm volatile ("dmb sy" : : : "memory")
+#else
+#error "Define barriers"
+#endif
+
+#endif /* XEN_BARRIER_H */
diff --git a/tools/include/xenctrl.h b/tools/include/xenctrl.h
index 29617585c5..ea57e9dbb9 100644
--- a/tools/include/xenctrl.h
+++ b/tools/include/xenctrl.h
@@ -48,6 +48,7 @@
#include <xen/platform.h>
#include "xentoollog.h"
+#include "xen-barrier.h"
#if defined(__i386__) || defined(__x86_64__)
#include <xen/foreign/x86_32.h>
@@ -61,33 +62,6 @@
#define INVALID_MFN (~0UL)
-/*
- * DEFINITIONS FOR CPU BARRIERS
- */
-
-#define xen_barrier() asm volatile ( "" : : : "memory")
-
-#if defined(__i386__)
-#define xen_mb() asm volatile ( "lock addl $0, -4(%%esp)" ::: "memory" )
-#define xen_rmb() xen_barrier()
-#define xen_wmb() xen_barrier()
-#elif defined(__x86_64__)
-#define xen_mb() asm volatile ( "lock addl $0, -32(%%rsp)" ::: "memory" )
-#define xen_rmb() xen_barrier()
-#define xen_wmb() xen_barrier()
-#elif defined(__arm__)
-#define xen_mb() asm volatile ("dmb" : : : "memory")
-#define xen_rmb() asm volatile ("dmb" : : : "memory")
-#define xen_wmb() asm volatile ("dmb" : : : "memory")
-#elif defined(__aarch64__)
-#define xen_mb() asm volatile ("dmb sy" : : : "memory")
-#define xen_rmb() asm volatile ("dmb sy" : : : "memory")
-#define xen_wmb() asm volatile ("dmb sy" : : : "memory")
-#else
-#error "Define barriers"
-#endif
-
-
#define XENCTRL_HAS_XC_INTERFACE 1
/* In Xen 4.0 and earlier, xc_interface_open and xc_evtchn_open would
* both return ints being the file descriptor. In 4.1 and later, they
diff --git a/tools/libs/ctrl/Makefile b/tools/libs/ctrl/Makefile
index 5fe0bfad0c..acce8639d3 100644
--- a/tools/libs/ctrl/Makefile
+++ b/tools/libs/ctrl/Makefile
@@ -3,7 +3,7 @@ include $(XEN_ROOT)/tools/Rules.mk
include Makefile.common
-LIBHEADER := xenctrl.h xenctrl_compat.h
+LIBHEADER := xenctrl.h xenctrl_compat.h xen-barrier.h
PKG_CONFIG_FILE := xencontrol.pc
PKG_CONFIG_NAME := Xencontrol
--
2.43.0
^ permalink raw reply related [flat|nested] 18+ messages in thread* Re: [PATCH v3 2/7] tools: add a dedicated header file for barrier definitions
2024-12-13 16:24 ` [PATCH v3 2/7] tools: add a dedicated header file for barrier definitions Juergen Gross
@ 2024-12-16 14:14 ` Anthony PERARD
0 siblings, 0 replies; 18+ messages in thread
From: Anthony PERARD @ 2024-12-16 14:14 UTC (permalink / raw)
To: Juergen Gross; +Cc: xen-devel
On Fri, Dec 13, 2024 at 05:24:16PM +0100, Juergen Gross wrote:
> diff --git a/tools/include/xen-barrier.h b/tools/include/xen-barrier.h
> new file mode 100644
> index 0000000000..a716fb93cc
> --- /dev/null
> +++ b/tools/include/xen-barrier.h
> @@ -0,0 +1,39 @@
> +/* SPDX-License-Identifier: LGPL-2.1 */
That's a deprecated SPDX identifier, it should be written
"LGPL-2.1-only" instead.
With that fixed: Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Thanks,
--
Anthony Perard | Vates XCP-ng Developer
XCP-ng & Xen Orchestra - Vates solutions
web: https://vates.tech
^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH v3 3/7] xen: add a domain unique id to each domain
2024-12-13 16:24 [PATCH v3 0/7] remove libxenctrl usage from xenstored Juergen Gross
2024-12-13 16:24 ` [PATCH v3 1/7] xen/xsm: make getdomaininfo xsm dummy checks more stringent Juergen Gross
2024-12-13 16:24 ` [PATCH v3 2/7] tools: add a dedicated header file for barrier definitions Juergen Gross
@ 2024-12-13 16:24 ` Juergen Gross
2024-12-13 16:24 ` [PATCH v3 4/7] xen: add bitmap to indicate per-domain state changes Juergen Gross
` (3 subsequent siblings)
6 siblings, 0 replies; 18+ messages in thread
From: Juergen Gross @ 2024-12-13 16:24 UTC (permalink / raw)
To: xen-devel
Cc: Juergen Gross, Andrew Cooper, Anthony PERARD, Michal Orzel,
Jan Beulich, Julien Grall, Roger Pau Monné,
Stefano Stabellini, Alejandro Vallejo
Xenstore is referencing domains by their domid, but reuse of a domid
can lead to the situation that Xenstore can't tell whether a domain
with that domid has been deleted and created again without Xenstore
noticing the domain is a new one now.
Add a global domain creation unique id which is updated when creating
a new domain, and store that value in struct domain of the new domain.
The global unique id is initialized with the system time and updates
are done via the xorshift algorithm which is used for pseudo random
number generation, too (see https://en.wikipedia.org/wiki/Xorshift).
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Alejandro Vallejo <alejandro.vallejo@cloud.com>
---
V1:
- make unique_id local to function (Jan Beulich)
- add lock (Julien Grall)
- add comment (Julien Grall)
V2:
- move reading unique_id into locked section (Julien Grall)
- add comment (Alejandro Vallejo)
---
xen/common/domain.c | 27 +++++++++++++++++++++++++++
xen/include/xen/sched.h | 3 +++
2 files changed, 30 insertions(+)
diff --git a/xen/common/domain.c b/xen/common/domain.c
index 92263a4fbd..e33a0a5a21 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -562,6 +562,32 @@ static void _domain_destroy(struct domain *d)
free_domain_struct(d);
}
+static uint64_t get_unique_id(void)
+{
+ static uint64_t unique_id;
+ static DEFINE_SPINLOCK(lock);
+ uint64_t x;
+
+ spin_lock(&lock);
+
+ x = unique_id ? : NOW();
+
+ /*
+ * Pseudo-randomize id in order to avoid consumers relying on sequence.
+ * Randomization algorithm has a period of 2^64 - 1.
+ * Unique id is not repeatable between resets and each id has the same
+ * lifetime as the domain it is associated with.
+ */
+ x ^= x << 13;
+ x ^= x >> 7;
+ x ^= x << 17;
+ unique_id = x;
+
+ spin_unlock(&lock);
+
+ return x;
+}
+
static int sanitise_domain_config(struct xen_domctl_createdomain *config)
{
bool hvm = config->flags & XEN_DOMCTL_CDF_hvm;
@@ -654,6 +680,7 @@ struct domain *domain_create(domid_t domid,
/* Sort out our idea of is_system_domain(). */
d->domain_id = domid;
+ d->unique_id = get_unique_id();
/* Holding CDF_* internal flags. */
d->cdf = flags;
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index 76e39378b3..711668e028 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -370,6 +370,9 @@ struct domain
domid_t domain_id;
unsigned int max_vcpus;
+
+ uint64_t unique_id; /* Unique domain identifier */
+
struct vcpu **vcpu;
shared_info_t *shared_info; /* shared data area */
--
2.43.0
^ permalink raw reply related [flat|nested] 18+ messages in thread* [PATCH v3 4/7] xen: add bitmap to indicate per-domain state changes
2024-12-13 16:24 [PATCH v3 0/7] remove libxenctrl usage from xenstored Juergen Gross
` (2 preceding siblings ...)
2024-12-13 16:24 ` [PATCH v3 3/7] xen: add a domain unique id to each domain Juergen Gross
@ 2024-12-13 16:24 ` Juergen Gross
2024-12-16 10:21 ` Jan Beulich
2024-12-13 16:24 ` [PATCH v3 5/7] xen: add new domctl get_changed_domain Juergen Gross
` (2 subsequent siblings)
6 siblings, 1 reply; 18+ messages in thread
From: Juergen Gross @ 2024-12-13 16:24 UTC (permalink / raw)
To: xen-devel
Cc: Juergen Gross, Andrew Cooper, Anthony PERARD, Michal Orzel,
Jan Beulich, Julien Grall, Roger Pau Monné,
Stefano Stabellini
Add a bitmap with one bit per possible domid indicating the respective
domain has changed its state (created, deleted, dying, crashed,
shutdown).
Registering the VIRQ_DOM_EXC event will result in setting the bits for
all existing domains and resetting all other bits.
As the usage of this bitmap is tightly coupled with the VIRQ_DOM_EXC
event, it is meant to be used only by a single consumer in the system,
just like the VIRQ_DOM_EXC event.
Resetting a bit will be done in a future patch.
This information is needed for Xenstore to keep track of all domains.
Signed-off-by: Juergen Gross <jgross@suse.com>
---
V2:
- use DOMID_FIRST_RESERVED instead of DOMID_MASK + 1 (Jan Beulich)
- use const (Jan Beulich)
- move call of domain_reset_states() into evtchn_bind_virq() (Jan Beulich)
- dynamically allocate dom_state_changed bitmap (Jan Beulich)
V3:
- use xvzalloc_array() (Jan Beulich)
- don't rename existing label (Jan Beulich)
---
xen/common/domain.c | 60 ++++++++++++++++++++++++++++++++++++++
xen/common/event_channel.c | 14 +++++++++
xen/include/xen/sched.h | 3 ++
3 files changed, 77 insertions(+)
diff --git a/xen/common/domain.c b/xen/common/domain.c
index e33a0a5a21..dab2344ef6 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -34,6 +34,7 @@
#include <xen/xenoprof.h>
#include <xen/irq.h>
#include <xen/argo.h>
+#include <xen/xvmalloc.h>
#include <asm/p2m.h>
#include <asm/processor.h>
#include <public/sched.h>
@@ -138,6 +139,60 @@ bool __read_mostly vmtrace_available;
bool __read_mostly vpmu_is_available;
+static DEFINE_SPINLOCK(dom_state_changed_lock);
+static unsigned long *dom_state_changed;
+
+int domain_init_states(void)
+{
+ const struct domain *d;
+ int rc = -ENOMEM;
+
+ spin_lock(&dom_state_changed_lock);
+
+ if ( dom_state_changed )
+ bitmap_zero(dom_state_changed, DOMID_FIRST_RESERVED);
+ else
+ {
+ dom_state_changed = xvzalloc_array(unsigned long,
+ BITS_TO_LONGS(DOMID_FIRST_RESERVED));
+ if ( !dom_state_changed )
+ goto unlock;
+ }
+
+ rcu_read_lock(&domlist_read_lock);
+
+ for_each_domain ( d )
+ set_bit(d->domain_id, dom_state_changed);
+
+ rcu_read_unlock(&domlist_read_lock);
+
+ rc = 0;
+
+ unlock:
+ spin_unlock(&dom_state_changed_lock);
+
+ return rc;
+}
+
+void domain_deinit_states(void)
+{
+ spin_lock(&dom_state_changed_lock);
+
+ XVFREE(dom_state_changed);
+
+ spin_unlock(&dom_state_changed_lock);
+}
+
+static void domain_changed_state(const struct domain *d)
+{
+ spin_lock(&dom_state_changed_lock);
+
+ if ( dom_state_changed )
+ set_bit(d->domain_id, dom_state_changed);
+
+ spin_unlock(&dom_state_changed_lock);
+}
+
static void __domain_finalise_shutdown(struct domain *d)
{
struct vcpu *v;
@@ -152,6 +207,7 @@ static void __domain_finalise_shutdown(struct domain *d)
return;
d->is_shut_down = 1;
+ domain_changed_state(d);
if ( (d->shutdown_code == SHUTDOWN_suspend) && d->suspend_evtchn )
evtchn_send(d, d->suspend_evtchn);
else
@@ -839,6 +895,7 @@ struct domain *domain_create(domid_t domid,
*/
domlist_insert(d);
+ domain_changed_state(d);
memcpy(d->handle, config->handle, sizeof(d->handle));
return d;
@@ -1104,6 +1161,7 @@ int domain_kill(struct domain *d)
/* Mem event cleanup has to go here because the rings
* have to be put before we call put_domain. */
vm_event_cleanup(d);
+ domain_changed_state(d);
put_domain(d);
send_global_virq(VIRQ_DOM_EXC);
/* fallthrough */
@@ -1293,6 +1351,8 @@ static void cf_check complete_domain_destroy(struct rcu_head *head)
xfree(d->vcpu);
+ domain_changed_state(d);
+
_domain_destroy(d);
send_global_virq(VIRQ_DOM_EXC);
diff --git a/xen/common/event_channel.c b/xen/common/event_channel.c
index 8db2ca4ba2..d18a756217 100644
--- a/xen/common/event_channel.c
+++ b/xen/common/event_channel.c
@@ -485,6 +485,13 @@ int evtchn_bind_virq(evtchn_bind_virq_t *bind, evtchn_port_t port)
if ( (v = domain_vcpu(d, vcpu)) == NULL )
return -ENOENT;
+ if ( virq == VIRQ_DOM_EXC )
+ {
+ rc = domain_init_states();
+ if ( rc )
+ goto deinit;
+ }
+
write_lock(&d->event_lock);
if ( read_atomic(&v->virq_to_evtchn[virq]) )
@@ -527,6 +534,10 @@ int evtchn_bind_virq(evtchn_bind_virq_t *bind, evtchn_port_t port)
out:
write_unlock(&d->event_lock);
+ deinit:
+ if ( rc )
+ domain_deinit_states();
+
return rc;
}
@@ -730,6 +741,9 @@ int evtchn_close(struct domain *d1, int port1, bool guest)
struct vcpu *v;
unsigned long flags;
+ if ( chn1->u.virq == VIRQ_DOM_EXC )
+ domain_deinit_states();
+
v = d1->vcpu[virq_is_global(chn1->u.virq) ? 0 : chn1->notify_vcpu_id];
write_lock_irqsave(&v->virq_lock, flags);
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index 711668e028..16684bbaf9 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -800,6 +800,9 @@ void domain_resume(struct domain *d);
int domain_soft_reset(struct domain *d, bool resuming);
+int domain_init_states(void);
+void domain_deinit_states(void);
+
int vcpu_start_shutdown_deferral(struct vcpu *v);
void vcpu_end_shutdown_deferral(struct vcpu *v);
--
2.43.0
^ permalink raw reply related [flat|nested] 18+ messages in thread* Re: [PATCH v3 4/7] xen: add bitmap to indicate per-domain state changes
2024-12-13 16:24 ` [PATCH v3 4/7] xen: add bitmap to indicate per-domain state changes Juergen Gross
@ 2024-12-16 10:21 ` Jan Beulich
2024-12-16 13:30 ` Jürgen Groß
0 siblings, 1 reply; 18+ messages in thread
From: Jan Beulich @ 2024-12-16 10:21 UTC (permalink / raw)
To: Juergen Gross
Cc: Andrew Cooper, Anthony PERARD, Michal Orzel, Julien Grall,
Roger Pau Monné, Stefano Stabellini, xen-devel
On 13.12.2024 17:24, Juergen Gross wrote:
> @@ -138,6 +139,60 @@ bool __read_mostly vmtrace_available;
>
> bool __read_mostly vpmu_is_available;
>
> +static DEFINE_SPINLOCK(dom_state_changed_lock);
> +static unsigned long *dom_state_changed;
__read_mostly?
> +int domain_init_states(void)
> +{
> + const struct domain *d;
> + int rc = -ENOMEM;
> +
> + spin_lock(&dom_state_changed_lock);
> +
> + if ( dom_state_changed )
> + bitmap_zero(dom_state_changed, DOMID_FIRST_RESERVED);
> + else
> + {
> + dom_state_changed = xvzalloc_array(unsigned long,
> + BITS_TO_LONGS(DOMID_FIRST_RESERVED));
> + if ( !dom_state_changed )
> + goto unlock;
> + }
> +
> + rcu_read_lock(&domlist_read_lock);
> +
> + for_each_domain ( d )
> + set_bit(d->domain_id, dom_state_changed);
Use the cheaper __set_bit() here?
> +static void domain_changed_state(const struct domain *d)
> +{
> + spin_lock(&dom_state_changed_lock);
> +
> + if ( dom_state_changed )
> + set_bit(d->domain_id, dom_state_changed);
And perhaps even here, considering everything's under lock now?
> --- a/xen/common/event_channel.c
> +++ b/xen/common/event_channel.c
> @@ -485,6 +485,13 @@ int evtchn_bind_virq(evtchn_bind_virq_t *bind, evtchn_port_t port)
> if ( (v = domain_vcpu(d, vcpu)) == NULL )
> return -ENOENT;
>
> + if ( virq == VIRQ_DOM_EXC )
> + {
> + rc = domain_init_states();
> + if ( rc )
> + goto deinit;
> + }
This is tied to VIRQ_DOM_EXC. How come ...
> @@ -527,6 +534,10 @@ int evtchn_bind_virq(evtchn_bind_virq_t *bind, evtchn_port_t port)
> out:
> write_unlock(&d->event_lock);
>
> + deinit:
> + if ( rc )
> + domain_deinit_states();
> +
> return rc;
> }
... de-init happens upon any error, regardless of vIRQ? Even checking
the virq isn't sufficient, as we also need to gracefully deal with the
-EEXIST path.
Jan
^ permalink raw reply [flat|nested] 18+ messages in thread* Re: [PATCH v3 4/7] xen: add bitmap to indicate per-domain state changes
2024-12-16 10:21 ` Jan Beulich
@ 2024-12-16 13:30 ` Jürgen Groß
0 siblings, 0 replies; 18+ messages in thread
From: Jürgen Groß @ 2024-12-16 13:30 UTC (permalink / raw)
To: Jan Beulich
Cc: Andrew Cooper, Anthony PERARD, Michal Orzel, Julien Grall,
Roger Pau Monné, Stefano Stabellini, xen-devel
[-- Attachment #1.1.1: Type: text/plain, Size: 2277 bytes --]
On 16.12.24 11:21, Jan Beulich wrote:
> On 13.12.2024 17:24, Juergen Gross wrote:
>> @@ -138,6 +139,60 @@ bool __read_mostly vmtrace_available;
>>
>> bool __read_mostly vpmu_is_available;
>>
>> +static DEFINE_SPINLOCK(dom_state_changed_lock);
>> +static unsigned long *dom_state_changed;
>
> __read_mostly?
Yes.
>
>> +int domain_init_states(void)
>> +{
>> + const struct domain *d;
>> + int rc = -ENOMEM;
>> +
>> + spin_lock(&dom_state_changed_lock);
>> +
>> + if ( dom_state_changed )
>> + bitmap_zero(dom_state_changed, DOMID_FIRST_RESERVED);
>> + else
>> + {
>> + dom_state_changed = xvzalloc_array(unsigned long,
>> + BITS_TO_LONGS(DOMID_FIRST_RESERVED));
>> + if ( !dom_state_changed )
>> + goto unlock;
>> + }
>> +
>> + rcu_read_lock(&domlist_read_lock);
>> +
>> + for_each_domain ( d )
>> + set_bit(d->domain_id, dom_state_changed);
>
> Use the cheaper __set_bit() here?
Okay.
>
>> +static void domain_changed_state(const struct domain *d)
>> +{
>> + spin_lock(&dom_state_changed_lock);
>> +
>> + if ( dom_state_changed )
>> + set_bit(d->domain_id, dom_state_changed);
>
> And perhaps even here, considering everything's under lock now?
True.
>
>> --- a/xen/common/event_channel.c
>> +++ b/xen/common/event_channel.c
>> @@ -485,6 +485,13 @@ int evtchn_bind_virq(evtchn_bind_virq_t *bind, evtchn_port_t port)
>> if ( (v = domain_vcpu(d, vcpu)) == NULL )
>> return -ENOENT;
>>
>> + if ( virq == VIRQ_DOM_EXC )
>> + {
>> + rc = domain_init_states();
>> + if ( rc )
>> + goto deinit;
>> + }
>
> This is tied to VIRQ_DOM_EXC. How come ...
>
>> @@ -527,6 +534,10 @@ int evtchn_bind_virq(evtchn_bind_virq_t *bind, evtchn_port_t port)
>> out:
>> write_unlock(&d->event_lock);
>>
>> + deinit:
>> + if ( rc )
>> + domain_deinit_states();
>> +
>> return rc;
>> }
>
> ... de-init happens upon any error, regardless of vIRQ? Even checking
> the virq isn't sufficient, as we also need to gracefully deal with the
> -EEXIST path.
Good catch. Will change that.
Juergen
[-- Attachment #1.1.2: OpenPGP public key --]
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[-- Attachment #2: OpenPGP digital signature --]
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^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH v3 5/7] xen: add new domctl get_changed_domain
2024-12-13 16:24 [PATCH v3 0/7] remove libxenctrl usage from xenstored Juergen Gross
` (3 preceding siblings ...)
2024-12-13 16:24 ` [PATCH v3 4/7] xen: add bitmap to indicate per-domain state changes Juergen Gross
@ 2024-12-13 16:24 ` Juergen Gross
2024-12-16 10:41 ` Jan Beulich
2024-12-13 16:24 ` [PATCH v3 6/7] tools/libs: add a new libxenmanage library Juergen Gross
2024-12-13 16:24 ` [PATCH v3 7/7] tools/xenstored: use new stable interface instead of libxenctrl Juergen Gross
6 siblings, 1 reply; 18+ messages in thread
From: Juergen Gross @ 2024-12-13 16:24 UTC (permalink / raw)
To: xen-devel
Cc: Juergen Gross, Daniel P. Smith, Anthony PERARD, Andrew Cooper,
Michal Orzel, Jan Beulich, Julien Grall, Roger Pau Monné,
Stefano Stabellini
Add a new domctl sub-function to get data of a domain having changed
state (this is needed by Xenstore).
The returned state just contains the domid, the domain unique id,
and some flags (existing, shutdown, dying).
In order to enable Xenstore stubdom being built for multiple Xen
versions, make this domctl stable. For stable domctls the
interface_version is always 0.
Signed-off-by: Juergen Gross <jgross@suse.com>
---
V1:
- use a domctl subop for the new interface (Jan Beulich)
V2:
- fix XSM hooks (Daniel P. Smith)
- remove versioning of stable sub-ops (Jan Beulich)
- use domctl.domain for retuning domid of a changed domain (Jan Beulich)
- simplify locking in get_domain_state() (Jan Beulich)
- undo stray change in event_channel.c (Jan Beulich)
V3:
- have disjunct states "dying" and "dead" (Jan Beulich)
- check padding fields to be 0 (Jan Beulich)
- drop memset() (Jan Beulich)
---
tools/flask/policy/modules/dom0.te | 2 +-
tools/flask/policy/modules/xen.if | 4 +-
tools/flask/policy/modules/xenstore.te | 1 +
xen/common/domain.c | 51 ++++++++++++++++++++++++++
xen/common/domctl.c | 18 ++++++++-
xen/include/public/domctl.h | 26 +++++++++++++
xen/include/xen/sched.h | 2 +
xen/include/xsm/dummy.h | 8 ++++
xen/include/xsm/xsm.h | 6 +++
xen/xsm/dummy.c | 1 +
xen/xsm/flask/hooks.c | 7 ++++
xen/xsm/flask/policy/access_vectors | 2 +
12 files changed, 124 insertions(+), 4 deletions(-)
diff --git a/tools/flask/policy/modules/dom0.te b/tools/flask/policy/modules/dom0.te
index 16b8c9646d..6043c01b12 100644
--- a/tools/flask/policy/modules/dom0.te
+++ b/tools/flask/policy/modules/dom0.te
@@ -40,7 +40,7 @@ allow dom0_t dom0_t:domain {
};
allow dom0_t dom0_t:domain2 {
set_cpu_policy gettsc settsc setscheduler set_vnumainfo
- get_vnumainfo psr_cmt_op psr_alloc get_cpu_policy
+ get_vnumainfo psr_cmt_op psr_alloc get_cpu_policy get_domain_state
};
allow dom0_t dom0_t:resource { add remove };
diff --git a/tools/flask/policy/modules/xen.if b/tools/flask/policy/modules/xen.if
index 11c1562aa5..2e06f3ed94 100644
--- a/tools/flask/policy/modules/xen.if
+++ b/tools/flask/policy/modules/xen.if
@@ -54,7 +54,7 @@ define(`create_domain_common', `
allow $1 $2:domain2 { set_cpu_policy settsc setscheduler setclaim
set_vnumainfo get_vnumainfo cacheflush
psr_cmt_op psr_alloc soft_reset
- resource_map get_cpu_policy };
+ resource_map get_cpu_policy get_domain_state };
allow $1 $2:security check_context;
allow $1 $2:shadow enable;
allow $1 $2:mmu { map_read map_write adjust memorymap physmap pinpage mmuext_op updatemp };
@@ -94,7 +94,7 @@ define(`manage_domain', `
getaddrsize pause unpause trigger shutdown destroy
setaffinity setdomainmaxmem getscheduler resume
setpodtarget getpodtarget getpagingmempool setpagingmempool };
- allow $1 $2:domain2 set_vnumainfo;
+ allow $1 $2:domain2 { set_vnumainfo get_domain_state };
')
# migrate_domain_out(priv, target)
diff --git a/tools/flask/policy/modules/xenstore.te b/tools/flask/policy/modules/xenstore.te
index 519566ab81..49de53ebe2 100644
--- a/tools/flask/policy/modules/xenstore.te
+++ b/tools/flask/policy/modules/xenstore.te
@@ -13,6 +13,7 @@ allow dom0_t xenstore_t:domain set_virq_handler;
allow xenstore_t xen_t:xen writeconsole;
# Xenstore queries domaininfo on all domains
allow xenstore_t domain_type:domain getdomaininfo;
+allow xenstore_t domain_type:domain2 get_domain_state;
# As a shortcut, the following 3 rules are used instead of adding a domain_comms
# rule between xenstore_t and every domain type that talks to xenstore
diff --git a/xen/common/domain.c b/xen/common/domain.c
index dab2344ef6..0073a1f445 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -193,6 +193,57 @@ static void domain_changed_state(const struct domain *d)
spin_unlock(&dom_state_changed_lock);
}
+static void set_domain_state_info(struct xen_domctl_get_domain_state *info,
+ const struct domain *d)
+{
+ info->state = XEN_DOMCTL_GETDOMSTATE_STATE_EXIST;
+ if ( d->is_shut_down )
+ info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_SHUTDOWN;
+ if ( d->is_dying == DOMDYING_dying )
+ info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DYING;
+ if ( d->is_dying == DOMDYING_dead )
+ info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DEAD;
+ info->unique_id = d->unique_id;
+}
+
+int get_domain_state(struct xen_domctl_get_domain_state *info, struct domain *d,
+ domid_t *domid)
+{
+ unsigned int dom;
+
+ if ( info->pad0 || info->pad1 )
+ return -EINVAL;
+
+ if ( d )
+ {
+ set_domain_state_info(info, d);
+
+ return 0;
+ }
+
+ while ( (dom = find_first_bit(dom_state_changed, DOMID_MASK + 1)) <
+ DOMID_FIRST_RESERVED )
+ {
+ if ( test_and_clear_bit(dom, dom_state_changed) )
+ {
+ *domid = dom;
+
+ d = rcu_lock_domain_by_id(dom);
+
+ if ( d )
+ {
+ set_domain_state_info(info, d);
+
+ rcu_unlock_domain(d);
+ }
+
+ return 0;
+ }
+ }
+
+ return -ENOENT;
+}
+
static void __domain_finalise_shutdown(struct domain *d)
{
struct vcpu *v;
diff --git a/xen/common/domctl.c b/xen/common/domctl.c
index 444e072fdc..802bd7596e 100644
--- a/xen/common/domctl.c
+++ b/xen/common/domctl.c
@@ -278,6 +278,11 @@ static struct vnuma_info *vnuma_init(const struct xen_domctl_vnuma *uinfo,
return ERR_PTR(ret);
}
+static bool is_stable_domctl(uint32_t cmd)
+{
+ return cmd == XEN_DOMCTL_get_domain_state;
+}
+
long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) u_domctl)
{
long ret = 0;
@@ -288,7 +293,8 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) u_domctl)
if ( copy_from_guest(op, u_domctl, 1) )
return -EFAULT;
- if ( op->interface_version != XEN_DOMCTL_INTERFACE_VERSION )
+ if ( op->interface_version !=
+ (is_stable_domctl(op->cmd) ? 0 : XEN_DOMCTL_INTERFACE_VERSION) )
return -EACCES;
switch ( op->cmd )
@@ -309,6 +315,7 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) u_domctl)
fallthrough;
case XEN_DOMCTL_test_assign_device:
case XEN_DOMCTL_vm_event_op:
+ case XEN_DOMCTL_get_domain_state:
if ( op->domain == DOMID_INVALID )
{
d = NULL;
@@ -866,6 +873,15 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) u_domctl)
__HYPERVISOR_domctl, "h", u_domctl);
break;
+ case XEN_DOMCTL_get_domain_state:
+ ret = xsm_get_domain_state(XSM_XS_PRIV, d);
+ if ( ret )
+ break;
+
+ copyback = 1;
+ ret = get_domain_state(&op->u.get_domain_state, d, &op->domain);
+ break;
+
default:
ret = arch_do_domctl(op, d, u_domctl);
break;
diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
index 353f831e40..13fe17ab0a 100644
--- a/xen/include/public/domctl.h
+++ b/xen/include/public/domctl.h
@@ -28,6 +28,7 @@
* Pure additions (e.g. new sub-commands) or compatible interface changes
* (e.g. adding semantics to 0-checked input fields or data to zeroed output
* fields) don't require a change of the version.
+ * Stable ops are NOT covered by XEN_DOMCTL_INTERFACE_VERSION!
*
* Last version bump: Xen 4.19
*/
@@ -1236,7 +1237,30 @@ struct xen_domctl_dt_overlay {
};
#endif
+/*
+ * XEN_DOMCTL_get_domain_state (stable interface)
+ *
+ * Get state information of a domain.
+ *
+ * In case domain is DOMID_INVALID, return information about a domain having
+ * changed state and reset the state change indicator for that domain. This
+ * function is usable only by a domain having registered the VIRQ_DOM_EXC
+ * event (normally Xenstore).
+ * NB. xen_domctl.domain is an IN/OUT parameter for this operation.
+ */
+struct xen_domctl_get_domain_state {
+ uint16_t state;
+#define XEN_DOMCTL_GETDOMSTATE_STATE_EXIST 0x0001 /* Domain is existing. */
+#define XEN_DOMCTL_GETDOMSTATE_STATE_SHUTDOWN 0x0002 /* Shutdown finished. */
+#define XEN_DOMCTL_GETDOMSTATE_STATE_DYING 0x0004 /* Domain dying. */
+#define XEN_DOMCTL_GETDOMSTATE_STATE_DEAD 0x0008 /* Domain dead. */
+ uint16_t pad0; /* Must be 0 on input, returned as 0. */
+ uint32_t pad1; /* Must be 0 on input, returned as 0. */
+ uint64_t unique_id; /* Unique domain identifier. */
+};
+
struct xen_domctl {
+/* Stable domctl ops: interface_version is required to be 0. */
uint32_t cmd;
#define XEN_DOMCTL_createdomain 1
#define XEN_DOMCTL_destroydomain 2
@@ -1325,6 +1349,7 @@ struct xen_domctl {
#define XEN_DOMCTL_set_paging_mempool_size 86
#define XEN_DOMCTL_dt_overlay 87
#define XEN_DOMCTL_gsi_permission 88
+#define XEN_DOMCTL_get_domain_state 89 /* stable interface */
#define XEN_DOMCTL_gdbsx_guestmemio 1000
#define XEN_DOMCTL_gdbsx_pausevcpu 1001
#define XEN_DOMCTL_gdbsx_unpausevcpu 1002
@@ -1391,6 +1416,7 @@ struct xen_domctl {
#if defined(__arm__) || defined(__aarch64__)
struct xen_domctl_dt_overlay dt_overlay;
#endif
+ struct xen_domctl_get_domain_state get_domain_state;
uint8_t pad[128];
} u;
};
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index 16684bbaf9..5e9858c3ba 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -802,6 +802,8 @@ int domain_soft_reset(struct domain *d, bool resuming);
int domain_init_states(void);
void domain_deinit_states(void);
+int get_domain_state(struct xen_domctl_get_domain_state *info,
+ struct domain *d, domid_t *domid);
int vcpu_start_shutdown_deferral(struct vcpu *v);
void vcpu_end_shutdown_deferral(struct vcpu *v);
diff --git a/xen/include/xsm/dummy.h b/xen/include/xsm/dummy.h
index f8a3c4b81e..a1a5bb60e9 100644
--- a/xen/include/xsm/dummy.h
+++ b/xen/include/xsm/dummy.h
@@ -173,6 +173,7 @@ static XSM_INLINE int cf_check xsm_domctl(
case XEN_DOMCTL_unbind_pt_irq:
return xsm_default_action(XSM_DM_PRIV, current->domain, d);
case XEN_DOMCTL_getdomaininfo:
+ case XEN_DOMCTL_get_domain_state:
return xsm_default_action(XSM_XS_PRIV, current->domain, d);
default:
return xsm_default_action(XSM_PRIV, current->domain, d);
@@ -815,6 +816,13 @@ static XSM_INLINE int cf_check xsm_argo_send(
#endif /* CONFIG_ARGO */
+static XSM_INLINE int cf_check xsm_get_domain_state(
+ XSM_DEFAULT_ARG struct domain *d)
+{
+ XSM_ASSERT_ACTION(XSM_XS_PRIV);
+ return xsm_default_action(action, current->domain, d);
+}
+
#include <public/version.h>
static XSM_INLINE int cf_check xsm_xen_version(XSM_DEFAULT_ARG uint32_t op)
{
diff --git a/xen/include/xsm/xsm.h b/xen/include/xsm/xsm.h
index 4dbff9d866..0689bf5c9f 100644
--- a/xen/include/xsm/xsm.h
+++ b/xen/include/xsm/xsm.h
@@ -200,6 +200,7 @@ struct xsm_ops {
int (*argo_register_any_source)(const struct domain *d);
int (*argo_send)(const struct domain *d, const struct domain *t);
#endif
+ int (*get_domain_state)(struct domain *d);
};
#ifdef CONFIG_XSM
@@ -774,6 +775,11 @@ static inline int xsm_argo_send(const struct domain *d, const struct domain *t)
#endif /* CONFIG_ARGO */
+static inline int xsm_get_domain_state(struct domain *d)
+{
+ return alternative_call(xsm_ops.get_domain_state, d);
+}
+
#endif /* XSM_NO_WRAPPERS */
#ifdef CONFIG_MULTIBOOT
diff --git a/xen/xsm/dummy.c b/xen/xsm/dummy.c
index e6ffa948f7..ce6fbdc6c5 100644
--- a/xen/xsm/dummy.c
+++ b/xen/xsm/dummy.c
@@ -148,6 +148,7 @@ static const struct xsm_ops __initconst_cf_clobber dummy_ops = {
.argo_register_any_source = xsm_argo_register_any_source,
.argo_send = xsm_argo_send,
#endif
+ .get_domain_state = xsm_get_domain_state,
};
void __init xsm_fixup_ops(struct xsm_ops *ops)
diff --git a/xen/xsm/flask/hooks.c b/xen/xsm/flask/hooks.c
index a79474ffe4..e110846ad9 100644
--- a/xen/xsm/flask/hooks.c
+++ b/xen/xsm/flask/hooks.c
@@ -688,6 +688,7 @@ static int cf_check flask_domctl(struct domain *d, unsigned int cmd,
case XEN_DOMCTL_memory_mapping:
case XEN_DOMCTL_set_target:
case XEN_DOMCTL_vm_event_op:
+ case XEN_DOMCTL_get_domain_state:
/* These have individual XSM hooks (arch/../domctl.c) */
case XEN_DOMCTL_bind_pt_irq:
@@ -1856,6 +1857,11 @@ static int cf_check flask_argo_send(
#endif
+static int cf_check flask_get_domain_state(struct domain *d)
+{
+ return current_has_perm(d, SECCLASS_DOMAIN2, DOMAIN2__GET_DOMAIN_STATE);
+}
+
static const struct xsm_ops __initconst_cf_clobber flask_ops = {
.set_system_active = flask_set_system_active,
.security_domaininfo = flask_security_domaininfo,
@@ -1992,6 +1998,7 @@ static const struct xsm_ops __initconst_cf_clobber flask_ops = {
.argo_register_any_source = flask_argo_register_any_source,
.argo_send = flask_argo_send,
#endif
+ .get_domain_state = flask_get_domain_state,
};
const struct xsm_ops *__init flask_init(
diff --git a/xen/xsm/flask/policy/access_vectors b/xen/xsm/flask/policy/access_vectors
index a35e3d4c51..c9a8eeda4e 100644
--- a/xen/xsm/flask/policy/access_vectors
+++ b/xen/xsm/flask/policy/access_vectors
@@ -251,6 +251,8 @@ class domain2
resource_map
# XEN_DOMCTL_get_cpu_policy
get_cpu_policy
+# XEN_DOMCTL_get_domain_state
+ get_domain_state
}
# Similar to class domain, but primarily contains domctls related to HVM domains
--
2.43.0
^ permalink raw reply related [flat|nested] 18+ messages in thread* Re: [PATCH v3 5/7] xen: add new domctl get_changed_domain
2024-12-13 16:24 ` [PATCH v3 5/7] xen: add new domctl get_changed_domain Juergen Gross
@ 2024-12-16 10:41 ` Jan Beulich
2024-12-16 13:57 ` Jürgen Groß
2024-12-16 15:03 ` Juergen Gross
0 siblings, 2 replies; 18+ messages in thread
From: Jan Beulich @ 2024-12-16 10:41 UTC (permalink / raw)
To: Juergen Gross
Cc: Daniel P. Smith, Anthony PERARD, Andrew Cooper, Michal Orzel,
Julien Grall, Roger Pau Monné, Stefano Stabellini, xen-devel
On 13.12.2024 17:24, Juergen Gross wrote:
> --- a/xen/common/domain.c
> +++ b/xen/common/domain.c
> @@ -193,6 +193,57 @@ static void domain_changed_state(const struct domain *d)
> spin_unlock(&dom_state_changed_lock);
> }
>
> +static void set_domain_state_info(struct xen_domctl_get_domain_state *info,
> + const struct domain *d)
> +{
> + info->state = XEN_DOMCTL_GETDOMSTATE_STATE_EXIST;
> + if ( d->is_shut_down )
> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_SHUTDOWN;
> + if ( d->is_dying == DOMDYING_dying )
> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DYING;
> + if ( d->is_dying == DOMDYING_dead )
> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DEAD;
> + info->unique_id = d->unique_id;
> +}
> +
> +int get_domain_state(struct xen_domctl_get_domain_state *info, struct domain *d,
> + domid_t *domid)
> +{
> + unsigned int dom;
> +
> + if ( info->pad0 || info->pad1 )
> + return -EINVAL;
> +
> + if ( d )
> + {
> + set_domain_state_info(info, d);
> +
> + return 0;
> + }
> +
> + while ( (dom = find_first_bit(dom_state_changed, DOMID_MASK + 1)) <
> + DOMID_FIRST_RESERVED )
> + {
> + if ( test_and_clear_bit(dom, dom_state_changed) )
For these two accesses to dom_state_changed don't you need to hold the
lock patch 4 introduces? Also didn't you say you'd constrain the new
sub-op to the sole domain having VIRQ_DOM_EXEC bound (which, ftaod,
isn't enough to eliminate the race)?
> + {
> + *domid = dom;
> +
> + d = rcu_lock_domain_by_id(dom);
> +
> + if ( d )
> + {
> + set_domain_state_info(info, d);
> +
> + rcu_unlock_domain(d);
> + }
Oh, on the implicit "else" is where the original memset() would come into
play: You want to make sure at least ->state, but perhaps also ->unique_id
are cleared (rather than demanding the caller to clear them ahead of making
the call).
Jan
^ permalink raw reply [flat|nested] 18+ messages in thread* Re: [PATCH v3 5/7] xen: add new domctl get_changed_domain
2024-12-16 10:41 ` Jan Beulich
@ 2024-12-16 13:57 ` Jürgen Groß
2024-12-16 15:03 ` Juergen Gross
1 sibling, 0 replies; 18+ messages in thread
From: Jürgen Groß @ 2024-12-16 13:57 UTC (permalink / raw)
To: Jan Beulich
Cc: Daniel P. Smith, Anthony PERARD, Andrew Cooper, Michal Orzel,
Julien Grall, Roger Pau Monné, Stefano Stabellini, xen-devel
[-- Attachment #1.1.1: Type: text/plain, Size: 2293 bytes --]
On 16.12.24 11:41, Jan Beulich wrote:
> On 13.12.2024 17:24, Juergen Gross wrote:
>> --- a/xen/common/domain.c
>> +++ b/xen/common/domain.c
>> @@ -193,6 +193,57 @@ static void domain_changed_state(const struct domain *d)
>> spin_unlock(&dom_state_changed_lock);
>> }
>>
>> +static void set_domain_state_info(struct xen_domctl_get_domain_state *info,
>> + const struct domain *d)
>> +{
>> + info->state = XEN_DOMCTL_GETDOMSTATE_STATE_EXIST;
>> + if ( d->is_shut_down )
>> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_SHUTDOWN;
>> + if ( d->is_dying == DOMDYING_dying )
>> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DYING;
>> + if ( d->is_dying == DOMDYING_dead )
>> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DEAD;
>> + info->unique_id = d->unique_id;
>> +}
>> +
>> +int get_domain_state(struct xen_domctl_get_domain_state *info, struct domain *d,
>> + domid_t *domid)
>> +{
>> + unsigned int dom;
>> +
>> + if ( info->pad0 || info->pad1 )
>> + return -EINVAL;
>> +
>> + if ( d )
>> + {
>> + set_domain_state_info(info, d);
>> +
>> + return 0;
>> + }
>> +
>> + while ( (dom = find_first_bit(dom_state_changed, DOMID_MASK + 1)) <
>> + DOMID_FIRST_RESERVED )
>> + {
>> + if ( test_and_clear_bit(dom, dom_state_changed) )
>
> For these two accesses to dom_state_changed don't you need to hold the
> lock patch 4 introduces? Also didn't you say you'd constrain the new
> sub-op to the sole domain having VIRQ_DOM_EXEC bound (which, ftaod,
> isn't enough to eliminate the race)?
Oh, indeed. Sorry for having missed both aspects.
>
>> + {
>> + *domid = dom;
>> +
>> + d = rcu_lock_domain_by_id(dom);
>> +
>> + if ( d )
>> + {
>> + set_domain_state_info(info, d);
>> +
>> + rcu_unlock_domain(d);
>> + }
>
> Oh, on the implicit "else" is where the original memset() would come into
> play: You want to make sure at least ->state, but perhaps also ->unique_id
> are cleared (rather than demanding the caller to clear them ahead of making
> the call).
Right.
Juergen
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^ permalink raw reply [flat|nested] 18+ messages in thread* Re: [PATCH v3 5/7] xen: add new domctl get_changed_domain
2024-12-16 10:41 ` Jan Beulich
2024-12-16 13:57 ` Jürgen Groß
@ 2024-12-16 15:03 ` Juergen Gross
2024-12-16 15:18 ` Jan Beulich
1 sibling, 1 reply; 18+ messages in thread
From: Juergen Gross @ 2024-12-16 15:03 UTC (permalink / raw)
To: Jan Beulich
Cc: Daniel P. Smith, Anthony PERARD, Andrew Cooper, Michal Orzel,
Julien Grall, Roger Pau Monné, Stefano Stabellini, xen-devel
[-- Attachment #1.1.1: Type: text/plain, Size: 2216 bytes --]
On 16.12.24 11:41, Jan Beulich wrote:
> On 13.12.2024 17:24, Juergen Gross wrote:
>> --- a/xen/common/domain.c
>> +++ b/xen/common/domain.c
>> @@ -193,6 +193,57 @@ static void domain_changed_state(const struct domain *d)
>> spin_unlock(&dom_state_changed_lock);
>> }
>>
>> +static void set_domain_state_info(struct xen_domctl_get_domain_state *info,
>> + const struct domain *d)
>> +{
>> + info->state = XEN_DOMCTL_GETDOMSTATE_STATE_EXIST;
>> + if ( d->is_shut_down )
>> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_SHUTDOWN;
>> + if ( d->is_dying == DOMDYING_dying )
>> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DYING;
>> + if ( d->is_dying == DOMDYING_dead )
>> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DEAD;
>> + info->unique_id = d->unique_id;
>> +}
>> +
>> +int get_domain_state(struct xen_domctl_get_domain_state *info, struct domain *d,
>> + domid_t *domid)
>> +{
>> + unsigned int dom;
>> +
>> + if ( info->pad0 || info->pad1 )
>> + return -EINVAL;
>> +
>> + if ( d )
>> + {
>> + set_domain_state_info(info, d);
>> +
>> + return 0;
>> + }
>> +
>> + while ( (dom = find_first_bit(dom_state_changed, DOMID_MASK + 1)) <
>> + DOMID_FIRST_RESERVED )
>> + {
>> + if ( test_and_clear_bit(dom, dom_state_changed) )
>
> For these two accesses to dom_state_changed don't you need to hold the
> lock patch 4 introduces? Also didn't you say you'd constrain the new
> sub-op to the sole domain having VIRQ_DOM_EXEC bound (which, ftaod,
> isn't enough to eliminate the race)?
Just to be more specific regarding the race: I guess you mean that a domain
having registered for the VIRQ doesn't mean the calling component being in
that domain really is the one associated with the VIRQ.
While being true, even today it is possible for one dom0 user process to
"steal" a VIRQ from another process by using dirty tricks via the privcmd
driver.
In the end a process having the access rights to use the privcmd driver must
be trusted to not disturb other processes with the same rights.
Juergen
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^ permalink raw reply [flat|nested] 18+ messages in thread* Re: [PATCH v3 5/7] xen: add new domctl get_changed_domain
2024-12-16 15:03 ` Juergen Gross
@ 2024-12-16 15:18 ` Jan Beulich
2024-12-16 15:20 ` Jürgen Groß
0 siblings, 1 reply; 18+ messages in thread
From: Jan Beulich @ 2024-12-16 15:18 UTC (permalink / raw)
To: Juergen Gross
Cc: Daniel P. Smith, Anthony PERARD, Andrew Cooper, Michal Orzel,
Julien Grall, Roger Pau Monné, Stefano Stabellini, xen-devel
On 16.12.2024 16:03, Juergen Gross wrote:
> On 16.12.24 11:41, Jan Beulich wrote:
>> On 13.12.2024 17:24, Juergen Gross wrote:
>>> --- a/xen/common/domain.c
>>> +++ b/xen/common/domain.c
>>> @@ -193,6 +193,57 @@ static void domain_changed_state(const struct domain *d)
>>> spin_unlock(&dom_state_changed_lock);
>>> }
>>>
>>> +static void set_domain_state_info(struct xen_domctl_get_domain_state *info,
>>> + const struct domain *d)
>>> +{
>>> + info->state = XEN_DOMCTL_GETDOMSTATE_STATE_EXIST;
>>> + if ( d->is_shut_down )
>>> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_SHUTDOWN;
>>> + if ( d->is_dying == DOMDYING_dying )
>>> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DYING;
>>> + if ( d->is_dying == DOMDYING_dead )
>>> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DEAD;
>>> + info->unique_id = d->unique_id;
>>> +}
>>> +
>>> +int get_domain_state(struct xen_domctl_get_domain_state *info, struct domain *d,
>>> + domid_t *domid)
>>> +{
>>> + unsigned int dom;
>>> +
>>> + if ( info->pad0 || info->pad1 )
>>> + return -EINVAL;
>>> +
>>> + if ( d )
>>> + {
>>> + set_domain_state_info(info, d);
>>> +
>>> + return 0;
>>> + }
>>> +
>>> + while ( (dom = find_first_bit(dom_state_changed, DOMID_MASK + 1)) <
>>> + DOMID_FIRST_RESERVED )
>>> + {
>>> + if ( test_and_clear_bit(dom, dom_state_changed) )
>>
>> For these two accesses to dom_state_changed don't you need to hold the
>> lock patch 4 introduces? Also didn't you say you'd constrain the new
>> sub-op to the sole domain having VIRQ_DOM_EXEC bound (which, ftaod,
>> isn't enough to eliminate the race)?
>
> Just to be more specific regarding the race: I guess you mean that a domain
> having registered for the VIRQ doesn't mean the calling component being in
> that domain really is the one associated with the VIRQ.
>
> While being true, even today it is possible for one dom0 user process to
> "steal" a VIRQ from another process by using dirty tricks via the privcmd
> driver.
>
> In the end a process having the access rights to use the privcmd driver must
> be trusted to not disturb other processes with the same rights.
Of course, but that's not exactly what I was getting at. I was trying to
point out that the vIRQ check alone is still insufficient to avoid potential
crashes here, by one vCPU calling here while another unbinds the vIRQ. Taking
the lock is required for Xen's safety; checking the vIRQ is bound is an extra
policy enforcement.
Jan
^ permalink raw reply [flat|nested] 18+ messages in thread* Re: [PATCH v3 5/7] xen: add new domctl get_changed_domain
2024-12-16 15:18 ` Jan Beulich
@ 2024-12-16 15:20 ` Jürgen Groß
0 siblings, 0 replies; 18+ messages in thread
From: Jürgen Groß @ 2024-12-16 15:20 UTC (permalink / raw)
To: Jan Beulich
Cc: Daniel P. Smith, Anthony PERARD, Andrew Cooper, Michal Orzel,
Julien Grall, Roger Pau Monné, Stefano Stabellini, xen-devel
[-- Attachment #1.1.1: Type: text/plain, Size: 2818 bytes --]
On 16.12.24 16:18, Jan Beulich wrote:
> On 16.12.2024 16:03, Juergen Gross wrote:
>> On 16.12.24 11:41, Jan Beulich wrote:
>>> On 13.12.2024 17:24, Juergen Gross wrote:
>>>> --- a/xen/common/domain.c
>>>> +++ b/xen/common/domain.c
>>>> @@ -193,6 +193,57 @@ static void domain_changed_state(const struct domain *d)
>>>> spin_unlock(&dom_state_changed_lock);
>>>> }
>>>>
>>>> +static void set_domain_state_info(struct xen_domctl_get_domain_state *info,
>>>> + const struct domain *d)
>>>> +{
>>>> + info->state = XEN_DOMCTL_GETDOMSTATE_STATE_EXIST;
>>>> + if ( d->is_shut_down )
>>>> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_SHUTDOWN;
>>>> + if ( d->is_dying == DOMDYING_dying )
>>>> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DYING;
>>>> + if ( d->is_dying == DOMDYING_dead )
>>>> + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DEAD;
>>>> + info->unique_id = d->unique_id;
>>>> +}
>>>> +
>>>> +int get_domain_state(struct xen_domctl_get_domain_state *info, struct domain *d,
>>>> + domid_t *domid)
>>>> +{
>>>> + unsigned int dom;
>>>> +
>>>> + if ( info->pad0 || info->pad1 )
>>>> + return -EINVAL;
>>>> +
>>>> + if ( d )
>>>> + {
>>>> + set_domain_state_info(info, d);
>>>> +
>>>> + return 0;
>>>> + }
>>>> +
>>>> + while ( (dom = find_first_bit(dom_state_changed, DOMID_MASK + 1)) <
>>>> + DOMID_FIRST_RESERVED )
>>>> + {
>>>> + if ( test_and_clear_bit(dom, dom_state_changed) )
>>>
>>> For these two accesses to dom_state_changed don't you need to hold the
>>> lock patch 4 introduces? Also didn't you say you'd constrain the new
>>> sub-op to the sole domain having VIRQ_DOM_EXEC bound (which, ftaod,
>>> isn't enough to eliminate the race)?
>>
>> Just to be more specific regarding the race: I guess you mean that a domain
>> having registered for the VIRQ doesn't mean the calling component being in
>> that domain really is the one associated with the VIRQ.
>>
>> While being true, even today it is possible for one dom0 user process to
>> "steal" a VIRQ from another process by using dirty tricks via the privcmd
>> driver.
>>
>> In the end a process having the access rights to use the privcmd driver must
>> be trusted to not disturb other processes with the same rights.
>
> Of course, but that's not exactly what I was getting at. I was trying to
> point out that the vIRQ check alone is still insufficient to avoid potential
> crashes here, by one vCPU calling here while another unbinds the vIRQ. Taking
> the lock is required for Xen's safety; checking the vIRQ is bound is an extra
> policy enforcement.
Ah, okay. I think V4 will cover your scenario.
Juergen
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^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH v3 6/7] tools/libs: add a new libxenmanage library
2024-12-13 16:24 [PATCH v3 0/7] remove libxenctrl usage from xenstored Juergen Gross
` (4 preceding siblings ...)
2024-12-13 16:24 ` [PATCH v3 5/7] xen: add new domctl get_changed_domain Juergen Gross
@ 2024-12-13 16:24 ` Juergen Gross
2024-12-16 14:49 ` Anthony PERARD
2024-12-13 16:24 ` [PATCH v3 7/7] tools/xenstored: use new stable interface instead of libxenctrl Juergen Gross
6 siblings, 1 reply; 18+ messages in thread
From: Juergen Gross @ 2024-12-13 16:24 UTC (permalink / raw)
To: xen-devel; +Cc: Juergen Gross, Anthony PERARD
In order to have a stable interface in user land for using stable
domctl and possibly later sysctl interfaces, add a new library
libxenmanage.
Signed-off-by: Juergen Gross <jgross@suse.com>
---
V1:
- new patch
V2:
- define __XEN_TOOLS__ via Makefile (Anthony PERARD)
- use SPDX in header file (Anthony PERARD)
- change function name to xenmanage_poll_changed_domain() (Anthony PERARD)
- add short library description (Anthony PERARD)
- narrow scope of xen_domctl_get_domain_state pointer (Anthony PERARD)
---
tools/include/xenmanage.h | 92 ++++++++++++++++
tools/libs/Makefile | 1 +
tools/libs/manage/Makefile | 10 ++
tools/libs/manage/Makefile.common | 3 +
tools/libs/manage/core.c | 168 +++++++++++++++++++++++++++++
tools/libs/manage/libxenmanage.map | 8 ++
tools/libs/uselibs.mk | 2 +
7 files changed, 284 insertions(+)
create mode 100644 tools/include/xenmanage.h
create mode 100644 tools/libs/manage/Makefile
create mode 100644 tools/libs/manage/Makefile.common
create mode 100644 tools/libs/manage/core.c
create mode 100644 tools/libs/manage/libxenmanage.map
diff --git a/tools/include/xenmanage.h b/tools/include/xenmanage.h
new file mode 100644
index 0000000000..5d169693b0
--- /dev/null
+++ b/tools/include/xenmanage.h
@@ -0,0 +1,92 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
+/*
+ * Copyright (c) 2024 SUSE Software Solutions Germany GmbH
+ *
+ * Interfaces of libxenmanage.
+ *
+ * libxenmanage provides management functions for the host using stable
+ * hypercall interfaces.
+ */
+#ifndef XENMANAGE_H
+#define XENMANAGE_H
+
+#include <stdint.h>
+
+/* Avoid the need to #include <xentoollog.h> */
+struct xentoollog_logger;
+
+typedef struct xenmanage_handle xenmanage_handle;
+
+/*
+ * Open libxenmanage.
+ *
+ * Get a handle of the xenmanage library. The handle is required for all
+ * further operations of the library.
+ * Parameters:
+ * logger: Logging function to use. If NULL logging is done to stderr.
+ * open_flags: Only 0 supported.
+ * Return value: Handle or NULL if error.
+ */
+xenmanage_handle *xenmanage_open(struct xentoollog_logger *logger,
+ unsigned int open_flags);
+
+/*
+ * Close libxenmanage.
+ *
+ * Return a handle of the xenmanage library.
+ * Parameters:
+ * hdl: Handle obtained by xenmanage_open().
+ * Return value: always 0.
+ */
+int xenmanage_close(xenmanage_handle *hdl);
+
+#define XENMANAGE_GETDOMSTATE_STATE_EXIST 0x0001 /* Domain is existing. */
+#define XENMANAGE_GETDOMSTATE_STATE_SHUTDOWN 0x0002 /* Shutdown finished. */
+#define XENMANAGE_GETDOMSTATE_STATE_DYING 0x0004 /* Domain dying. */
+#define XENMANAGE_GETDOMSTATE_STATE_DEAD 0x0008 /* Domain dead. */
+
+/*
+ * Return state information of an existing domain.
+ *
+ * Returns the domain state and unique id of the given domain.
+ * Parameters:
+ * hdl: handle returned by xenmanage_open()
+ * domid: domain id of the domain to get the information for
+ * state: where to store the state (XENMANAGE_GETDOMSTATE_STATE_ flags,
+ * nothing stored if NULL)
+ * unique_id: where to store the unique id of the domain (nothing stored if
+ * NULL)
+ * Return value: 0 if information was stored, -1 else (errno is set)
+ */
+int xenmanage_get_domain_info(xenmanage_handle *hdl, unsigned int domid,
+ unsigned int *state, uint64_t *unique_id);
+
+/*
+ * Return information of a domain having changed state recently.
+ *
+ * Returns the domain id, state and unique id of a domain having changed
+ * state (any of the state bits was modified) since the last time information
+ * for that domain was returned by this function. Only usable by callers who
+ * have registered the VIRQ_DOM_EXC event (normally Xenstore).
+ * Parameters:
+ * hdl: handle returned by xenmanage_open()
+ * domid: where to store the domid of the domain (not NULL)
+ * state: where to store the state (XENMANAGE_GETDOMSTATE_STATE_ flags,
+ * nothing stored if NULL)
+ * unique_id: where to store the unique id of the domain (nothing stored if
+ * NULL)
+ * Return value: 0 if information was stored, -1 else (errno is set)
+ */
+int xenmanage_poll_changed_domain(xenmanage_handle *hdl, unsigned int *domid,
+ unsigned int *state, uint64_t *unique_id);
+#endif /* XENMANAGE_H */
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/libs/Makefile b/tools/libs/Makefile
index 1afcd12e2b..d39516c1b3 100644
--- a/tools/libs/Makefile
+++ b/tools/libs/Makefile
@@ -12,6 +12,7 @@ SUBDIRS-y += devicemodel
SUBDIRS-y += ctrl
SUBDIRS-y += guest
SUBDIRS-y += hypfs
+SUBDIRS-y += manage
SUBDIRS-y += store
SUBDIRS-y += stat
SUBDIRS-$(CONFIG_Linux) += vchan
diff --git a/tools/libs/manage/Makefile b/tools/libs/manage/Makefile
new file mode 100644
index 0000000000..dbfe70d259
--- /dev/null
+++ b/tools/libs/manage/Makefile
@@ -0,0 +1,10 @@
+XEN_ROOT = $(CURDIR)/../../..
+include $(XEN_ROOT)/tools/Rules.mk
+
+MAJOR = 1
+MINOR = 0
+version-script := libxenmanage.map
+
+include Makefile.common
+
+include $(XEN_ROOT)/tools/libs/libs.mk
diff --git a/tools/libs/manage/Makefile.common b/tools/libs/manage/Makefile.common
new file mode 100644
index 0000000000..533ba30fba
--- /dev/null
+++ b/tools/libs/manage/Makefile.common
@@ -0,0 +1,3 @@
+CFLAGS += -D__XEN_TOOLS__
+
+OBJS-y += core.o
diff --git a/tools/libs/manage/core.c b/tools/libs/manage/core.c
new file mode 100644
index 0000000000..b5fa67b036
--- /dev/null
+++ b/tools/libs/manage/core.c
@@ -0,0 +1,168 @@
+/*
+ * Copyright (c) 2024 SUSE Software Solutions Germany GmbH
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define _GNU_SOURCE
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <xentoollog.h>
+#include <xenmanage.h>
+#include <xencall.h>
+#include <xentoolcore_internal.h>
+
+#include <xen/xen.h>
+#include <xen/domctl.h>
+
+struct xenmanage_handle {
+ xentoollog_logger *logger, *logger_tofree;
+ unsigned int flags;
+ xencall_handle *xcall;
+};
+
+xenmanage_handle *xenmanage_open(xentoollog_logger *logger,
+ unsigned open_flags)
+{
+ xenmanage_handle *hdl = calloc(1, sizeof(*hdl));
+ int saved_errno;
+
+ if ( !hdl )
+ return NULL;
+
+ if ( open_flags )
+ {
+ errno = EINVAL;
+ goto err;
+ }
+
+ hdl->flags = open_flags;
+ hdl->logger = logger;
+ hdl->logger_tofree = NULL;
+
+ if ( !hdl->logger )
+ {
+ hdl->logger = hdl->logger_tofree =
+ (xentoollog_logger *)
+ xtl_createlogger_stdiostream(stderr, XTL_PROGRESS, 0);
+ if ( !hdl->logger )
+ goto err;
+ }
+
+ hdl->xcall = xencall_open(hdl->logger, 0);
+ if ( !hdl->xcall )
+ goto err;
+
+ return hdl;
+
+err:
+ saved_errno = errno;
+ xenmanage_close(hdl);
+ errno = saved_errno;
+
+ return NULL;
+}
+
+int xenmanage_close(xenmanage_handle *hdl)
+{
+ if ( !hdl )
+ return 0;
+
+ xencall_close(hdl->xcall);
+ xtl_logger_destroy(hdl->logger_tofree);
+ free(hdl);
+ return 0;
+}
+
+static int xenmanage_do_domctl_get_domain_state(xenmanage_handle *hdl,
+ unsigned int domid_in,
+ unsigned int *domid_out,
+ unsigned int *state,
+ uint64_t *unique_id)
+{
+ struct xen_domctl *buf;
+ int saved_errno;
+ int ret;
+
+ buf = xencall_alloc_buffer(hdl->xcall, sizeof(*buf));
+ if ( !buf )
+ {
+ errno = ENOMEM;
+ return -1;
+ }
+
+ memset(buf, 0, sizeof(*buf));
+
+ buf->cmd = XEN_DOMCTL_get_domain_state;
+ buf->domain = domid_in;
+
+ ret = xencall1(hdl->xcall, __HYPERVISOR_domctl, (unsigned long)buf);
+ saved_errno = errno;
+ if ( !ret )
+ {
+ struct xen_domctl_get_domain_state *st = &buf->u.get_domain_state;
+
+ if ( domid_out )
+ *domid_out = buf->domain;
+ if ( state )
+ {
+ *state = 0;
+ if ( st->state & XEN_DOMCTL_GETDOMSTATE_STATE_EXIST )
+ *state |= XENMANAGE_GETDOMSTATE_STATE_EXIST;
+ if ( st->state & XEN_DOMCTL_GETDOMSTATE_STATE_SHUTDOWN )
+ *state |= XENMANAGE_GETDOMSTATE_STATE_SHUTDOWN;
+ if ( st->state & XEN_DOMCTL_GETDOMSTATE_STATE_DYING )
+ *state |= XENMANAGE_GETDOMSTATE_STATE_DYING;
+ if ( st->state & XEN_DOMCTL_GETDOMSTATE_STATE_DEAD )
+ *state |= XENMANAGE_GETDOMSTATE_STATE_DEAD;
+ }
+ if ( unique_id )
+ *unique_id = st->unique_id;
+ }
+
+ xencall_free_buffer(hdl->xcall, buf);
+
+ errno = saved_errno;
+
+ return ret;
+}
+
+int xenmanage_get_domain_info(xenmanage_handle *hdl, unsigned int domid,
+ unsigned int *state, uint64_t *unique_id)
+{
+ if ( !hdl || domid >= DOMID_FIRST_RESERVED )
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ return xenmanage_do_domctl_get_domain_state(hdl, domid, NULL, state,
+ unique_id);
+}
+
+int xenmanage_poll_changed_domain(xenmanage_handle *hdl, unsigned int *domid,
+ unsigned int *state, uint64_t *unique_id)
+{
+ if ( !hdl || !domid )
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ return xenmanage_do_domctl_get_domain_state(hdl, DOMID_INVALID, domid,
+ state, unique_id);
+}
diff --git a/tools/libs/manage/libxenmanage.map b/tools/libs/manage/libxenmanage.map
new file mode 100644
index 0000000000..64c793e603
--- /dev/null
+++ b/tools/libs/manage/libxenmanage.map
@@ -0,0 +1,8 @@
+VERS_1.0 {
+ global:
+ xenmanage_open;
+ xenmanage_close;
+ xenmanage_get_domain_info;
+ xenmanage_poll_changed_domain;
+ local: *; /* Do not expose anything by default */
+};
diff --git a/tools/libs/uselibs.mk b/tools/libs/uselibs.mk
index 7aa8d83e06..c0a234cfec 100644
--- a/tools/libs/uselibs.mk
+++ b/tools/libs/uselibs.mk
@@ -16,6 +16,8 @@ LIBS_LIBS += devicemodel
USELIBS_devicemodel := toollog toolcore call
LIBS_LIBS += hypfs
USELIBS_hypfs := toollog toolcore call
+LIBS_LIBS += manage
+USELIBS_manage := toollog toolcore call
LIBS_LIBS += ctrl
USELIBS_ctrl := toollog call evtchn gnttab foreignmemory devicemodel
LIBS_LIBS += guest
--
2.43.0
^ permalink raw reply related [flat|nested] 18+ messages in thread* Re: [PATCH v3 6/7] tools/libs: add a new libxenmanage library
2024-12-13 16:24 ` [PATCH v3 6/7] tools/libs: add a new libxenmanage library Juergen Gross
@ 2024-12-16 14:49 ` Anthony PERARD
2024-12-16 15:15 ` Juergen Gross
0 siblings, 1 reply; 18+ messages in thread
From: Anthony PERARD @ 2024-12-16 14:49 UTC (permalink / raw)
To: Juergen Gross; +Cc: xen-devel
On Fri, Dec 13, 2024 at 05:24:20PM +0100, Juergen Gross wrote:
> diff --git a/tools/include/xenmanage.h b/tools/include/xenmanage.h
> new file mode 100644
> index 0000000000..5d169693b0
> --- /dev/null
> +++ b/tools/include/xenmanage.h
> @@ -0,0 +1,92 @@
> +/* SPDX-License-Identifier: LGPL-2.1 */
This should read "LGPL-2.1-only".
> diff --git a/tools/libs/manage/core.c b/tools/libs/manage/core.c
> new file mode 100644
> index 0000000000..b5fa67b036
> --- /dev/null
> +++ b/tools/libs/manage/core.c
> @@ -0,0 +1,168 @@
> +static int xenmanage_do_domctl_get_domain_state(xenmanage_handle *hdl,
> + unsigned int domid_in,
> + unsigned int *domid_out,
> + unsigned int *state,
> + uint64_t *unique_id)
> +{
> + struct xen_domctl *buf;
> + int saved_errno;
> + int ret;
> +
> + buf = xencall_alloc_buffer(hdl->xcall, sizeof(*buf));
> + if ( !buf )
> + {
> + errno = ENOMEM;
Is this necessary? Isn't xencall_alloc_buffer() going to set `errno`? Or
is it to overwrite `errno` set by system calls which could be other than
ENOMEM?
> + return -1;
> + }
Otherwise, patch looks fine to me: Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Thanks,
--
Anthony Perard | Vates XCP-ng Developer
XCP-ng & Xen Orchestra - Vates solutions
web: https://vates.tech
^ permalink raw reply [flat|nested] 18+ messages in thread* Re: [PATCH v3 6/7] tools/libs: add a new libxenmanage library
2024-12-16 14:49 ` Anthony PERARD
@ 2024-12-16 15:15 ` Juergen Gross
0 siblings, 0 replies; 18+ messages in thread
From: Juergen Gross @ 2024-12-16 15:15 UTC (permalink / raw)
To: Anthony PERARD; +Cc: xen-devel
[-- Attachment #1.1.1: Type: text/plain, Size: 1687 bytes --]
On 16.12.24 15:49, Anthony PERARD wrote:
> On Fri, Dec 13, 2024 at 05:24:20PM +0100, Juergen Gross wrote:
>> diff --git a/tools/include/xenmanage.h b/tools/include/xenmanage.h
>> new file mode 100644
>> index 0000000000..5d169693b0
>> --- /dev/null
>> +++ b/tools/include/xenmanage.h
>> @@ -0,0 +1,92 @@
>> +/* SPDX-License-Identifier: LGPL-2.1 */
>
> This should read "LGPL-2.1-only".
Okay.
>
>> diff --git a/tools/libs/manage/core.c b/tools/libs/manage/core.c
>> new file mode 100644
>> index 0000000000..b5fa67b036
>> --- /dev/null
>> +++ b/tools/libs/manage/core.c
>> @@ -0,0 +1,168 @@
>
>> +static int xenmanage_do_domctl_get_domain_state(xenmanage_handle *hdl,
>> + unsigned int domid_in,
>> + unsigned int *domid_out,
>> + unsigned int *state,
>> + uint64_t *unique_id)
>> +{
>> + struct xen_domctl *buf;
>> + int saved_errno;
>> + int ret;
>> +
>> + buf = xencall_alloc_buffer(hdl->xcall, sizeof(*buf));
>> + if ( !buf )
>> + {
>> + errno = ENOMEM;
>
> Is this necessary? Isn't xencall_alloc_buffer() going to set `errno`? Or
> is it to overwrite `errno` set by system calls which could be other than
> ENOMEM?
There are many different errno values thinkable. I want to make sure
to have a value making clear that the allocation failed for some reason.
>
>> + return -1;
>> + }
>
> Otherwise, patch looks fine to me: Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Thanks,
Juergen
[-- Attachment #1.1.2: OpenPGP public key --]
[-- Type: application/pgp-keys, Size: 3743 bytes --]
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 495 bytes --]
^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH v3 7/7] tools/xenstored: use new stable interface instead of libxenctrl
2024-12-13 16:24 [PATCH v3 0/7] remove libxenctrl usage from xenstored Juergen Gross
` (5 preceding siblings ...)
2024-12-13 16:24 ` [PATCH v3 6/7] tools/libs: add a new libxenmanage library Juergen Gross
@ 2024-12-13 16:24 ` Juergen Gross
6 siblings, 0 replies; 18+ messages in thread
From: Juergen Gross @ 2024-12-13 16:24 UTC (permalink / raw)
To: xen-devel; +Cc: Juergen Gross, Anthony PERARD, Samuel Thibault, Julien Grall
Replace the current use of the unstable xc_domain_getinfo_single()
interface with the stable domctl XEN_DOMCTL_get_domain_state call
via the new libxenmanage library.
This will remove the last usage of libxenctrl by Xenstore, so update
the library dependencies accordingly.
For now only do a direct replacement without using the functionality
of obtaining information about domains having changed the state.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
---
V1:
- use library instead of direct hypercall, only replace current
libxenctrl use case
Please note that this patch can be committed only after the related
Mini-OS patch "config: add support for libxenmanage" has gone in AND
the Mini-OS commit-id has been updated in Config.mk accordingly!
Signed-off-by: Juergen Gross <jgross@suse.com>
---
stubdom/Makefile | 8 ++---
stubdom/mini-os.mk | 1 +
tools/xenstored/Makefile | 2 +-
tools/xenstored/Makefile.common | 2 +-
tools/xenstored/core.h | 1 -
tools/xenstored/domain.c | 52 ++++++++++++---------------------
tools/xenstored/lu.c | 1 +
tools/xenstored/lu_daemon.c | 1 +
8 files changed, 28 insertions(+), 40 deletions(-)
diff --git a/stubdom/Makefile b/stubdom/Makefile
index 2a81af28a1..ca800b243c 100644
--- a/stubdom/Makefile
+++ b/stubdom/Makefile
@@ -307,7 +307,7 @@ endif
# libraries under tools/libs
#######
-STUB_LIBS := toolcore toollog evtchn gnttab call foreignmemory devicemodel ctrl guest
+STUB_LIBS := toolcore toollog evtchn gnttab call foreignmemory devicemodel ctrl guest manage
LIBDEP_guest := cross-zlib
@@ -465,7 +465,7 @@ grub: cross-polarssl grub-upstream $(CROSS_ROOT) grub-$(XEN_TARGET_ARCH)-minios-
# xenstore
##########
-xenstore-minios.gen.cfg: APP_LIBS = gnttab evtchn toollog ctrl
+xenstore-minios.gen.cfg: APP_LIBS = gnttab evtchn toollog manage
xenstore-minios.gen.cfg: xenstore-minios.cfg Makefile
$(GEN_config) >$@
@@ -480,7 +480,7 @@ xenstore: $(CROSS_ROOT) xenstore-minios-config.mk
# xenstorepvh
#############
-xenstorepvh-minios.gen.cfg: APP_LIBS = gnttab evtchn toollog ctrl
+xenstorepvh-minios.gen.cfg: APP_LIBS = gnttab evtchn toollog manage
xenstorepvh-minios.gen.cfg: xenstorepvh-minios.cfg Makefile
$(GEN_config) >$@
@@ -523,7 +523,7 @@ else
pv-grub-if-enabled:
endif
-XENSTORE_DEPS := libxenevtchn libxengnttab libxenctrl
+XENSTORE_DEPS := libxenevtchn libxengnttab libxenmanage
.PHONY: xenstore-stubdom
xenstore-stubdom: mini-os-$(XEN_TARGET_ARCH)-xenstore $(XENSTORE_DEPS) xenstore
diff --git a/stubdom/mini-os.mk b/stubdom/mini-os.mk
index 7e4968e026..be32302f9e 100644
--- a/stubdom/mini-os.mk
+++ b/stubdom/mini-os.mk
@@ -13,5 +13,6 @@ GNTTAB_PATH = $(XEN_ROOT)/stubdom/libs-$(MINIOS_TARGET_ARCH)/gnttab
CALL_PATH = $(XEN_ROOT)/stubdom/libs-$(MINIOS_TARGET_ARCH)/call
FOREIGNMEMORY_PATH = $(XEN_ROOT)/stubdom/libs-$(MINIOS_TARGET_ARCH)/foreignmemory
DEVICEMODEL_PATH = $(XEN_ROOT)/stubdom/libs-$(MINIOS_TARGET_ARCH)/devicemodel
+MANAGE_PATH = $(XEN_ROOT)/stubdom/libs-$(MINIOS_TARGET_ARCH)/manage
CTRL_PATH = $(XEN_ROOT)/stubdom/libs-$(MINIOS_TARGET_ARCH)/ctrl
GUEST_PATH = $(XEN_ROOT)/stubdom/libs-$(MINIOS_TARGET_ARCH)/guest
diff --git a/tools/xenstored/Makefile b/tools/xenstored/Makefile
index 09adfe1d50..81c42838e0 100644
--- a/tools/xenstored/Makefile
+++ b/tools/xenstored/Makefile
@@ -5,7 +5,7 @@ include Makefile.common
xenstored: LDLIBS += $(LDLIBS_libxenevtchn)
xenstored: LDLIBS += $(LDLIBS_libxengnttab)
-xenstored: LDLIBS += $(LDLIBS_libxenctrl)
+xenstored: LDLIBS += $(LDLIBS_libxenmanage)
xenstored: LDLIBS += -lrt
xenstored: LDLIBS += $(SOCKET_LIBS)
diff --git a/tools/xenstored/Makefile.common b/tools/xenstored/Makefile.common
index 27fdb3b49e..271134fcc1 100644
--- a/tools/xenstored/Makefile.common
+++ b/tools/xenstored/Makefile.common
@@ -12,7 +12,7 @@ XENSTORED_OBJS-$(CONFIG_MiniOS) += minios.o lu_minios.o
# Include configure output (config.h)
CFLAGS += -include $(XEN_ROOT)/tools/config.h
CFLAGS += $(CFLAGS_libxenevtchn)
-CFLAGS += $(CFLAGS_libxenctrl)
+CFLAGS += $(CFLAGS_libxenmanage)
CFLAGS += $(CFLAGS_libxentoolcore)
$(XENSTORED_OBJS-y): CFLAGS += $(CFLAGS_libxengnttab)
diff --git a/tools/xenstored/core.h b/tools/xenstored/core.h
index e58779e88c..632886cecf 100644
--- a/tools/xenstored/core.h
+++ b/tools/xenstored/core.h
@@ -19,7 +19,6 @@
#ifndef _XENSTORED_CORE_H
#define _XENSTORED_CORE_H
-#include <xenctrl.h>
#include <xengnttab.h>
#include <sys/types.h>
diff --git a/tools/xenstored/domain.c b/tools/xenstored/domain.c
index 64c8fd0cc3..a6506a5bb2 100644
--- a/tools/xenstored/domain.c
+++ b/tools/xenstored/domain.c
@@ -34,14 +34,15 @@
#include "control.h"
#include <xenevtchn.h>
-#include <xenctrl.h>
+#include <xenmanage.h>
+#include <xen-barrier.h>
#include <xen/grant_table.h>
#ifdef __MINIOS__
#include <mini-os/xenbus.h>
#endif
-static xc_interface **xc_handle;
+static xenmanage_handle *xm_handle;
xengnttab_handle **xgt_handle;
static evtchn_port_t virq_port;
@@ -619,32 +620,28 @@ static int destroy_domain(void *_domain)
return 0;
}
-static bool get_domain_info(unsigned int domid, xc_domaininfo_t *dominfo)
-{
- return xc_domain_getinfo_single(*xc_handle, domid, dominfo) == 0;
-}
-
static int check_domain(const void *k, void *v, void *arg)
{
- xc_domaininfo_t dominfo;
+ unsigned int state;
struct connection *conn;
- bool dom_valid;
+ int dom_invalid;
struct domain *domain = v;
bool *notify = arg;
- dom_valid = get_domain_info(domain->domid, &dominfo);
+ dom_invalid = xenmanage_get_domain_info(xm_handle, domain->domid,
+ &state, NULL);
if (!domain->introduced) {
- if (!dom_valid)
+ if (dom_invalid)
talloc_free(domain);
return 0;
}
- if (dom_valid) {
- if ((dominfo.flags & XEN_DOMINF_shutdown)
+ if (!dom_invalid) {
+ if ((state & XENMANAGE_GETDOMSTATE_STATE_SHUTDOWN)
&& !domain->shutdown) {
domain->shutdown = true;
*notify = true;
}
- if (!(dominfo.flags & XEN_DOMINF_dying))
+ if (!(state & XENMANAGE_GETDOMSTATE_STATE_DEAD))
return 0;
}
if (domain->conn) {
@@ -786,10 +783,9 @@ static struct domain *find_or_alloc_domain(const void *ctx, unsigned int domid)
static struct domain *find_or_alloc_existing_domain(unsigned int domid)
{
struct domain *domain;
- xc_domaininfo_t dominfo;
domain = find_domain_struct(domid);
- if (!domain && get_domain_info(domid, &dominfo))
+ if (!domain && !xenmanage_get_domain_info(xm_handle, domid, NULL, NULL))
domain = alloc_domain(NULL, domid);
return domain;
@@ -1187,12 +1183,6 @@ int do_reset_watches(const void *ctx, struct connection *conn,
return 0;
}
-static int close_xc_handle(void *_handle)
-{
- xc_interface_close(*(xc_interface**)_handle);
- return 0;
-}
-
static int close_xgt_handle(void *_handle)
{
xengnttab_close(*(xengnttab_handle **)_handle);
@@ -1258,15 +1248,9 @@ void domain_early_init(void)
if (!domhash)
barf_perror("Failed to allocate domain hashtable");
- xc_handle = talloc(talloc_autofree_context(), xc_interface*);
- if (!xc_handle)
- barf_perror("Failed to allocate domain handle");
-
- *xc_handle = xc_interface_open(0,0,0);
- if (!*xc_handle)
- barf_perror("Failed to open connection to hypervisor");
-
- talloc_set_destructor(xc_handle, close_xc_handle);
+ xm_handle = xenmanage_open(NULL, 0);
+ if (!xm_handle)
+ barf_perror("Failed to open connection to libxenmanage");
xgt_handle = talloc(talloc_autofree_context(), xengnttab_handle*);
if (!xgt_handle)
@@ -1306,6 +1290,8 @@ void domain_deinit(void)
{
if (virq_port)
xenevtchn_unbind(xce_handle, virq_port);
+
+ xenmanage_close(xm_handle);
}
/*
@@ -1335,13 +1321,13 @@ int domain_alloc_permrefs(struct node_perms *perms)
{
unsigned int i, domid;
struct domain *d;
- xc_domaininfo_t dominfo;
for (i = 0; i < perms->num; i++) {
domid = perms->p[i].id;
d = find_domain_struct(domid);
if (!d) {
- if (!get_domain_info(domid, &dominfo))
+ if (xenmanage_get_domain_info(xm_handle, domid,
+ NULL, NULL))
perms->p[i].perms |= XS_PERM_IGNORE;
else if (!alloc_domain(NULL, domid))
return ENOMEM;
diff --git a/tools/xenstored/lu.c b/tools/xenstored/lu.c
index bec2a84e10..4fccbbc195 100644
--- a/tools/xenstored/lu.c
+++ b/tools/xenstored/lu.c
@@ -11,6 +11,7 @@
#include <stdlib.h>
#include <syslog.h>
#include <time.h>
+#include <unistd.h>
#include <sys/mman.h>
#include <sys/stat.h>
diff --git a/tools/xenstored/lu_daemon.c b/tools/xenstored/lu_daemon.c
index 6df6c80a2a..88d8d9e1b3 100644
--- a/tools/xenstored/lu_daemon.c
+++ b/tools/xenstored/lu_daemon.c
@@ -6,6 +6,7 @@
*/
#include <syslog.h>
+#include <unistd.h>
#include <sys/stat.h>
#include "talloc.h"
--
2.43.0
^ permalink raw reply related [flat|nested] 18+ messages in thread