| Message ID | 1467786055-85835-16-git-send-email-imammedo@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
* Igor Mammedov (imammedo@redhat.com) wrote: > instance_id is generated by last_used_id + 1 for a given device type > so for QEMU with 3 CPUs instance_id for APICs is a seti of [0, 1, 2] > When CPU in the middle is hot-removed and migration started > APICs with instance_ids 0 and 2 are transferred in migration stream. > However target starts with 2 CPUs and APICs' instance_ids are > generated from scratch [0, 1] hence migration fails with error > Unknown savevm section or instance 'apic' 2 > > Fix issue by manually registering APIC's vmsd with apic_id as > instance_id, in this case instance_id on target will always > match instance_id on source as apic_id is the same for a given > cpu instance. > > Reported-by: Bharata B Rao <bharata@linux.vnet.ibm.com> > Signed-off-by: Igor Mammedov <imammedo@redhat.com> OK, I think this works from the migration side of things. The old version used the qdev registration but since you didn't have a bus it was still the simple "apic" naming, so I don't think that changes. Since you're tieing it to machine type we never have to worry about clashes between the old and new numbering. So, from the migration side of things I think this is about as simple a fix as we're going to see, although I'm expecting you're running into similar problems in other devices. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Dave > --- > hw/intc/apic_common.c | 12 +++++++++++- > include/hw/i386/apic_internal.h | 1 + > include/hw/i386/pc.h | 5 +++++ > 3 files changed, 17 insertions(+), 1 deletion(-) > > diff --git a/hw/intc/apic_common.c b/hw/intc/apic_common.c > index 0bb9ad5..14ac43c 100644 > --- a/hw/intc/apic_common.c > +++ b/hw/intc/apic_common.c > @@ -294,11 +294,14 @@ static int apic_load_old(QEMUFile *f, void *opaque, int version_id) > return 0; > } > > +static const VMStateDescription vmstate_apic_common; > + > static void apic_common_realize(DeviceState *dev, Error **errp) > { > APICCommonState *s = APIC_COMMON(dev); > APICCommonClass *info; > static DeviceState *vapic; > + int instance_id = s->id; > > info = APIC_COMMON_GET_CLASS(s); > info->realize(dev, errp); > @@ -313,6 +316,11 @@ static void apic_common_realize(DeviceState *dev, Error **errp) > info->enable_tpr_reporting(s, true); > } > > + if (s->legacy_instance_id) { > + instance_id = -1; > + } > + vmstate_register_with_alias_id(NULL, instance_id, &vmstate_apic_common, > + s, -1, 0); > } > > static void apic_common_unrealize(DeviceState *dev, Error **errp) > @@ -320,6 +328,7 @@ static void apic_common_unrealize(DeviceState *dev, Error **errp) > APICCommonState *s = APIC_COMMON(dev); > APICCommonClass *info = APIC_COMMON_GET_CLASS(s); > > + vmstate_unregister(NULL, &vmstate_apic_common, s); > info->unrealize(dev, errp); > > if (apic_report_tpr_access && info->enable_tpr_reporting) { > @@ -422,6 +431,8 @@ static Property apic_properties_common[] = { > DEFINE_PROP_UINT8("version", APICCommonState, version, 0x14), > DEFINE_PROP_BIT("vapic", APICCommonState, vapic_control, VAPIC_ENABLE_BIT, > true), > + DEFINE_PROP_BOOL("legacy-instance-id", APICCommonState, legacy_instance_id, > + false), > DEFINE_PROP_END_OF_LIST(), > }; > > @@ -429,7 +440,6 @@ static void apic_common_class_init(ObjectClass *klass, void *data) > { > DeviceClass *dc = DEVICE_CLASS(klass); > > - dc->vmsd = &vmstate_apic_common; > dc->reset = apic_reset_common; > dc->props = apic_properties_common; > dc->realize = apic_common_realize; > diff --git a/include/hw/i386/apic_internal.h b/include/hw/i386/apic_internal.h > index 52ca45d..a694322 100644 > --- a/include/hw/i386/apic_internal.h > +++ b/include/hw/i386/apic_internal.h > @@ -182,6 +182,7 @@ struct APICCommonState { > uint32_t vapic_control; > DeviceState *vapic; > hwaddr vapic_paddr; /* note: persistence via kvmvapic */ > + bool legacy_instance_id; > }; > > typedef struct VAPICState { > diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h > index 7e43b20..e2f0426 100644 > --- a/include/hw/i386/pc.h > +++ b/include/hw/i386/pc.h > @@ -374,6 +374,11 @@ bool e820_get_entry(int, uint32_t, uint64_t *, uint64_t *); > .driver = TYPE_X86_CPU,\ > .property = "cpuid-0xb",\ > .value = "off",\ > + },\ > + {\ > + .driver = "apic",\ > + .property = "legacy-instance-id",\ > + .value = "on",\ > }, > > #define PC_COMPAT_2_5 \ > -- > 2.7.0 > > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
diff --git a/hw/intc/apic_common.c b/hw/intc/apic_common.c index 0bb9ad5..14ac43c 100644 --- a/hw/intc/apic_common.c +++ b/hw/intc/apic_common.c @@ -294,11 +294,14 @@ static int apic_load_old(QEMUFile *f, void *opaque, int version_id) return 0; } +static const VMStateDescription vmstate_apic_common; + static void apic_common_realize(DeviceState *dev, Error **errp) { APICCommonState *s = APIC_COMMON(dev); APICCommonClass *info; static DeviceState *vapic; + int instance_id = s->id; info = APIC_COMMON_GET_CLASS(s); info->realize(dev, errp); @@ -313,6 +316,11 @@ static void apic_common_realize(DeviceState *dev, Error **errp) info->enable_tpr_reporting(s, true); } + if (s->legacy_instance_id) { + instance_id = -1; + } + vmstate_register_with_alias_id(NULL, instance_id, &vmstate_apic_common, + s, -1, 0); } static void apic_common_unrealize(DeviceState *dev, Error **errp) @@ -320,6 +328,7 @@ static void apic_common_unrealize(DeviceState *dev, Error **errp) APICCommonState *s = APIC_COMMON(dev); APICCommonClass *info = APIC_COMMON_GET_CLASS(s); + vmstate_unregister(NULL, &vmstate_apic_common, s); info->unrealize(dev, errp); if (apic_report_tpr_access && info->enable_tpr_reporting) { @@ -422,6 +431,8 @@ static Property apic_properties_common[] = { DEFINE_PROP_UINT8("version", APICCommonState, version, 0x14), DEFINE_PROP_BIT("vapic", APICCommonState, vapic_control, VAPIC_ENABLE_BIT, true), + DEFINE_PROP_BOOL("legacy-instance-id", APICCommonState, legacy_instance_id, + false), DEFINE_PROP_END_OF_LIST(), }; @@ -429,7 +440,6 @@ static void apic_common_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); - dc->vmsd = &vmstate_apic_common; dc->reset = apic_reset_common; dc->props = apic_properties_common; dc->realize = apic_common_realize; diff --git a/include/hw/i386/apic_internal.h b/include/hw/i386/apic_internal.h index 52ca45d..a694322 100644 --- a/include/hw/i386/apic_internal.h +++ b/include/hw/i386/apic_internal.h @@ -182,6 +182,7 @@ struct APICCommonState { uint32_t vapic_control; DeviceState *vapic; hwaddr vapic_paddr; /* note: persistence via kvmvapic */ + bool legacy_instance_id; }; typedef struct VAPICState { diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h index 7e43b20..e2f0426 100644 --- a/include/hw/i386/pc.h +++ b/include/hw/i386/pc.h @@ -374,6 +374,11 @@ bool e820_get_entry(int, uint32_t, uint64_t *, uint64_t *); .driver = TYPE_X86_CPU,\ .property = "cpuid-0xb",\ .value = "off",\ + },\ + {\ + .driver = "apic",\ + .property = "legacy-instance-id",\ + .value = "on",\ }, #define PC_COMPAT_2_5 \
instance_id is generated by last_used_id + 1 for a given device type so for QEMU with 3 CPUs instance_id for APICs is a seti of [0, 1, 2] When CPU in the middle is hot-removed and migration started APICs with instance_ids 0 and 2 are transferred in migration stream. However target starts with 2 CPUs and APICs' instance_ids are generated from scratch [0, 1] hence migration fails with error Unknown savevm section or instance 'apic' 2 Fix issue by manually registering APIC's vmsd with apic_id as instance_id, in this case instance_id on target will always match instance_id on source as apic_id is the same for a given cpu instance. Reported-by: Bharata B Rao <bharata@linux.vnet.ibm.com> Signed-off-by: Igor Mammedov <imammedo@redhat.com> --- hw/intc/apic_common.c | 12 +++++++++++- include/hw/i386/apic_internal.h | 1 + include/hw/i386/pc.h | 5 +++++ 3 files changed, 17 insertions(+), 1 deletion(-)