target-i386: block migration and savevm if invariant tsc is exposed

Invariant TSC documentation mentions that "invariant TSC will run at a
constant rate in all ACPI P-, C-. and T-states".

This is not the case if migration to a host with different TSC frequency
is allowed, or if savevm is performed. So block migration/savevm.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[AF+mtosatti: Updated error message]
Signed-off-by: Andreas Färber <afaerber@suse.de>
This commit is contained in:
Marcelo Tosatti 2014-05-14 16:30:09 -03:00 committed by Andreas Färber
parent 7d854c471a
commit 68bfd0ad4a
3 changed files with 17 additions and 2 deletions

View File

@ -121,7 +121,7 @@ static inline X86CPU *x86_env_get_cpu(CPUX86State *env)
#define ENV_OFFSET offsetof(X86CPU, env)
#ifndef CONFIG_USER_ONLY
extern const struct VMStateDescription vmstate_x86_cpu;
extern struct VMStateDescription vmstate_x86_cpu;
#endif
/**

View File

@ -35,6 +35,8 @@
#include "exec/ioport.h"
#include <asm/hyperv.h>
#include "hw/pci/pci.h"
#include "migration/migration.h"
#include "qapi/qmp/qerror.h"
//#define DEBUG_KVM
@ -448,6 +450,8 @@ static bool hyperv_enabled(X86CPU *cpu)
cpu->hyperv_relaxed_timing);
}
static Error *invtsc_mig_blocker;
#define KVM_MAX_CPUID_ENTRIES 100
int kvm_arch_init_vcpu(CPUState *cs)
@ -705,6 +709,17 @@ int kvm_arch_init_vcpu(CPUState *cs)
!!(c->ecx & CPUID_EXT_SMX);
}
c = cpuid_find_entry(&cpuid_data.cpuid, 0x80000007, 0);
if (c && (c->edx & 1<<8) && invtsc_mig_blocker == NULL) {
/* for migration */
error_setg(&invtsc_mig_blocker,
"State blocked by non-migratable CPU device"
" (invtsc flag)");
migrate_add_blocker(invtsc_mig_blocker);
/* for savevm */
vmstate_x86_cpu.unmigratable = 1;
}
cpuid_data.cpuid.padding = 0;
r = kvm_vcpu_ioctl(cs, KVM_SET_CPUID2, &cpuid_data);
if (r) {

View File

@ -603,7 +603,7 @@ static const VMStateDescription vmstate_msr_hyperv_time = {
}
};
const VMStateDescription vmstate_x86_cpu = {
VMStateDescription vmstate_x86_cpu = {
.name = "cpu",
.version_id = 12,
.minimum_version_id = 3,