target-i386: Report known CPUID[EAX=0xD,ECX=0]:EAX bits as migratable

A regression was introduced by commit 96193c22a "target-i386:
Move xsave component mask to features array": all
CPUID[EAX=0xD,ECX=0]:EAX bits were being reported as unmigratable
because they don't have feature names defined. This broke
"-cpu host" because it enables only migratable features by
default.

This adds a new field to FeatureWordInfo: migratable_flags, which
will make those features be reported as migratable even if they
don't have a property name defined.

Reported-by: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Paolo Bonzini <bonzini@gnu.org>
Reviewed-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
This commit is contained in:
Eduardo Habkost 2016-09-28 12:00:29 -03:00
parent c5d128ffeb
commit 6fb2fff75d

View File

@ -258,6 +258,7 @@ typedef struct FeatureWordInfo {
int cpuid_reg; /* output register (R_* constant) */
uint32_t tcg_features; /* Feature flags supported by TCG */
uint32_t unmigratable_flags; /* Feature flags known to be unmigratable */
uint32_t migratable_flags; /* Feature flags known to be migratable */
} FeatureWordInfo;
static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
@ -494,6 +495,10 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
.cpuid_needs_ecx = true, .cpuid_ecx = 0,
.cpuid_reg = R_EAX,
.tcg_features = ~0U,
.migratable_flags = XSTATE_FP_MASK | XSTATE_SSE_MASK |
XSTATE_YMM_MASK | XSTATE_BNDREGS_MASK | XSTATE_BNDCSR_MASK |
XSTATE_OPMASK_MASK | XSTATE_ZMM_Hi256_MASK | XSTATE_Hi16_ZMM_MASK |
XSTATE_PKRU_MASK,
},
[FEAT_XSAVE_COMP_HI] = {
.cpuid_eax = 0xD,
@ -600,16 +605,14 @@ static uint32_t x86_cpu_get_migratable_flags(FeatureWord w)
for (i = 0; i < 32; i++) {
uint32_t f = 1U << i;
/* If the feature name is unknown, it is not supported by QEMU yet */
if (!wi->feat_names[i]) {
continue;
}
/* Skip features known to QEMU, but explicitly marked as unmigratable */
if (wi->unmigratable_flags & f) {
continue;
}
/* If the feature name is known, it is implicitly considered migratable,
* unless it is explicitly set in unmigratable_flags */
if ((wi->migratable_flags & f) ||
(wi->feat_names[i] && !(wi->unmigratable_flags & f))) {
r |= f;
}
}
return r;
}