* [Qemu-devel] [PULL 1/3] spapr: Correctly set query_hotpluggable_cpus hook based on machine version
2016-08-08 2:44 [Qemu-devel] [PULL 0/3] ppc-for-2.7 queue 20160808 David Gibson
@ 2016-08-08 2:44 ` David Gibson
2016-08-08 2:44 ` [Qemu-devel] [PULL 2/3] macio: set res_count value to 0 after non-block ATAPI DMA transfers David Gibson
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: David Gibson @ 2016-08-08 2:44 UTC (permalink / raw)
To: peter.maydell
Cc: agraf, qemu-ppc, qemu-devel, bharata, imammedo, David Gibson
Prior to c8721d3 "spapr: Error out when CPU hotplug is attempted on older
pseries machines", attempting to use query-hotpluggable-cpus on pseries-2.6
and earlier machine types would SEGV.
That change fixed that, but due to some unexpected interactions in init
order and a brown-paper-bag worthy failure to test, it accidentally
disabled query-hotpluggable-cpus for all pseries machine types, including
the current one which should allow it.
In fact, query_hotpluggable_cpus needs to be non-NULL when and only when
the dr_cpu_enabled flag in sPAPRMachineClass is set, which makes
dr_cpu_enabled itself redundant.
This patch removes dr_cpu_enabled, instead directly setting
query_hotpluggable_cpus from the machine class_init functions, and using
that to determine the availability of CPU hotplug when necessary.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
hw/ppc/spapr.c | 24 +++++++++---------------
hw/ppc/spapr_cpu_core.c | 7 ++-----
include/hw/ppc/spapr.h | 1 -
3 files changed, 11 insertions(+), 21 deletions(-)
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index bce2371..57564e5 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -938,6 +938,7 @@ static void spapr_finalize_fdt(sPAPRMachineState *spapr,
hwaddr rtas_size)
{
MachineState *machine = MACHINE(qdev_get_machine());
+ MachineClass *mc = MACHINE_GET_CLASS(machine);
sPAPRMachineClass *smc = SPAPR_MACHINE_GET_CLASS(machine);
const char *boot_device = machine->boot_order;
int ret, i;
@@ -1020,7 +1021,7 @@ static void spapr_finalize_fdt(sPAPRMachineState *spapr,
_FDT(spapr_drc_populate_dt(fdt, 0, NULL, SPAPR_DR_CONNECTOR_TYPE_LMB));
}
- if (smc->dr_cpu_enabled) {
+ if (mc->query_hotpluggable_cpus) {
int offset = fdt_path_offset(fdt, "/cpus");
ret = spapr_drc_populate_dt(fdt, offset, NULL,
SPAPR_DR_CONNECTOR_TYPE_CPU);
@@ -1712,6 +1713,7 @@ static void spapr_validate_node_memory(MachineState *machine, Error **errp)
static void ppc_spapr_init(MachineState *machine)
{
sPAPRMachineState *spapr = SPAPR_MACHINE(machine);
+ MachineClass *mc = MACHINE_GET_CLASS(machine);
sPAPRMachineClass *smc = SPAPR_MACHINE_GET_CLASS(machine);
const char *kernel_filename = machine->kernel_filename;
const char *kernel_cmdline = machine->kernel_cmdline;
@@ -1733,7 +1735,7 @@ static void ppc_spapr_init(MachineState *machine)
int spapr_cores = smp_cpus / smp_threads;
int spapr_max_cores = max_cpus / smp_threads;
- if (smc->dr_cpu_enabled) {
+ if (mc->query_hotpluggable_cpus) {
if (smp_cpus % smp_threads) {
error_report("smp_cpus (%u) must be multiple of threads (%u)",
smp_cpus, smp_threads);
@@ -1810,7 +1812,7 @@ static void ppc_spapr_init(MachineState *machine)
machine->cpu_model = kvm_enabled() ? "host" : "POWER7";
}
- if (smc->dr_cpu_enabled) {
+ if (mc->query_hotpluggable_cpus) {
char *type = spapr_get_cpu_core_type(machine->cpu_model);
spapr->cores = g_new0(Object *, spapr_max_cores);
@@ -2333,12 +2335,12 @@ static void spapr_machine_device_plug(HotplugHandler *hotplug_dev,
static void spapr_machine_device_unplug(HotplugHandler *hotplug_dev,
DeviceState *dev, Error **errp)
{
- sPAPRMachineClass *smc = SPAPR_MACHINE_GET_CLASS(qdev_get_machine());
+ MachineClass *mc = MACHINE_GET_CLASS(qdev_get_machine());
if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
error_setg(errp, "Memory hot unplug not supported by sPAPR");
} else if (object_dynamic_cast(OBJECT(dev), TYPE_SPAPR_CPU_CORE)) {
- if (!smc->dr_cpu_enabled) {
+ if (!mc->query_hotpluggable_cpus) {
error_setg(errp, "CPU hot unplug not supported on this machine");
return;
}
@@ -2376,11 +2378,8 @@ static HotpluggableCPUList *spapr_query_hotpluggable_cpus(MachineState *machine)
int i;
HotpluggableCPUList *head = NULL;
sPAPRMachineState *spapr = SPAPR_MACHINE(machine);
- sPAPRMachineClass *smc = SPAPR_MACHINE_GET_CLASS(machine);
int spapr_max_cores = max_cpus / smp_threads;
- g_assert(smc->dr_cpu_enabled);
-
for (i = 0; i < spapr_max_cores; i++) {
HotpluggableCPUList *list_item = g_new0(typeof(*list_item), 1);
HotpluggableCPU *cpu_item = g_new0(typeof(*cpu_item), 1);
@@ -2435,12 +2434,9 @@ static void spapr_machine_class_init(ObjectClass *oc, void *data)
hc->plug = spapr_machine_device_plug;
hc->unplug = spapr_machine_device_unplug;
mc->cpu_index_to_socket_id = spapr_cpu_index_to_socket_id;
- if (smc->dr_cpu_enabled) {
- mc->query_hotpluggable_cpus = spapr_query_hotpluggable_cpus;
- }
smc->dr_lmb_enabled = true;
- smc->dr_cpu_enabled = true;
+ mc->query_hotpluggable_cpus = spapr_query_hotpluggable_cpus;
fwc->get_dev_path = spapr_get_fw_dev_path;
nc->nmi_monitor_handler = spapr_nmi;
}
@@ -2521,10 +2517,8 @@ static void spapr_machine_2_6_instance_options(MachineState *machine)
static void spapr_machine_2_6_class_options(MachineClass *mc)
{
- sPAPRMachineClass *smc = SPAPR_MACHINE_CLASS(mc);
-
spapr_machine_2_7_class_options(mc);
- smc->dr_cpu_enabled = false;
+ mc->query_hotpluggable_cpus = NULL;
SET_MACHINE_COMPAT(mc, SPAPR_COMPAT_2_6);
}
diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c
index 170ed15..704803a 100644
--- a/hw/ppc/spapr_cpu_core.c
+++ b/hw/ppc/spapr_cpu_core.c
@@ -153,7 +153,6 @@ void spapr_core_unplug(HotplugHandler *hotplug_dev, DeviceState *dev,
void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
Error **errp)
{
- sPAPRMachineClass *smc = SPAPR_MACHINE_GET_CLASS(OBJECT(hotplug_dev));
sPAPRMachineState *spapr = SPAPR_MACHINE(OBJECT(hotplug_dev));
sPAPRCPUCore *core = SPAPR_CPU_CORE(OBJECT(dev));
CPUCore *cc = CPU_CORE(dev);
@@ -166,8 +165,6 @@ void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
int index = cc->core_id / smp_threads;
int smt = kvmppc_smt_threads();
- g_assert(smc->dr_cpu_enabled);
-
drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_CPU, index * smt);
spapr->cores[index] = OBJECT(dev);
@@ -209,7 +206,7 @@ void spapr_core_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
Error **errp)
{
MachineState *machine = MACHINE(OBJECT(hotplug_dev));
- sPAPRMachineClass *smc = SPAPR_MACHINE_GET_CLASS(OBJECT(hotplug_dev));
+ MachineClass *mc = MACHINE_GET_CLASS(hotplug_dev);
sPAPRMachineState *spapr = SPAPR_MACHINE(OBJECT(hotplug_dev));
int spapr_max_cores = max_cpus / smp_threads;
int index;
@@ -218,7 +215,7 @@ void spapr_core_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
char *base_core_type = spapr_get_cpu_core_type(machine->cpu_model);
const char *type = object_get_typename(OBJECT(dev));
- if (!smc->dr_cpu_enabled) {
+ if (!mc->query_hotpluggable_cpus) {
error_setg(&local_err, "CPU hotplug not supported for this machine");
goto out;
}
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index bd8ac28..caf7be9 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -38,7 +38,6 @@ struct sPAPRMachineClass {
/*< public >*/
bool dr_lmb_enabled; /* enable dynamic-reconfig/hotplug of LMBs */
- bool dr_cpu_enabled; /* enable dynamic-reconfig/hotplug of CPUs */
bool use_ohci_by_default; /* use USB-OHCI instead of XHCI */
};
--
2.7.4
^ permalink raw reply related [flat|nested] 5+ messages in thread* [Qemu-devel] [PULL 3/3] spapr: Fix undefined behaviour in spapr_tce_reset()
2016-08-08 2:44 [Qemu-devel] [PULL 0/3] ppc-for-2.7 queue 20160808 David Gibson
2016-08-08 2:44 ` [Qemu-devel] [PULL 1/3] spapr: Correctly set query_hotpluggable_cpus hook based on machine version David Gibson
2016-08-08 2:44 ` [Qemu-devel] [PULL 2/3] macio: set res_count value to 0 after non-block ATAPI DMA transfers David Gibson
@ 2016-08-08 2:44 ` David Gibson
2016-08-08 11:41 ` [Qemu-devel] [PULL 0/3] ppc-for-2.7 queue 20160808 Peter Maydell
3 siblings, 0 replies; 5+ messages in thread
From: David Gibson @ 2016-08-08 2:44 UTC (permalink / raw)
To: peter.maydell
Cc: agraf, qemu-ppc, qemu-devel, bharata, imammedo, David Gibson
When a TCE table (sPAPR IOMMU context) is in disabled state (which is true
by default for the 64-bit window), it has tcet->nb_table == 0 and
tcet->table == NULL. However, on system reset, spapr_tce_reset() executes,
which unconditionally calls
memset(tcet->table, 0, table_size);
We get away with this in practice, because it's a zero length memset(),
but memset() on a NULL pointer is undefined behaviour, so we should not
call it in this case.
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
hw/ppc/spapr_iommu.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/hw/ppc/spapr_iommu.c b/hw/ppc/spapr_iommu.c
index d57b05d..6bc4d4d 100644
--- a/hw/ppc/spapr_iommu.c
+++ b/hw/ppc/spapr_iommu.c
@@ -385,7 +385,9 @@ static void spapr_tce_reset(DeviceState *dev)
sPAPRTCETable *tcet = SPAPR_TCE_TABLE(dev);
size_t table_size = tcet->nb_table * sizeof(uint64_t);
- memset(tcet->table, 0, table_size);
+ if (tcet->nb_table) {
+ memset(tcet->table, 0, table_size);
+ }
}
static target_ulong put_tce_emu(sPAPRTCETable *tcet, target_ulong ioba,
--
2.7.4
^ permalink raw reply related [flat|nested] 5+ messages in thread