Right now, QEMU is using the "feature" and "bits" fields of ExtSaveArea
to query the accelerator for the support status of extended save areas.
This is a problem for AVX10, which attaches two feature bits (AVX512F
and AVX10) to the same extended save states.
To keep the AVX10 hacks to the minimum, limit usage of esa->features
and esa->bits. Instead, just query the accelerator for the 0xD leaf.
Do it in common code and clear esa->size if an extended save state is
unsupported.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
target/i386/cpu.c | 33 +++++++++++++++++++++++++++++++--
target/i386/kvm/kvm-cpu.c | 4 ----
2 files changed, 31 insertions(+), 6 deletions(-)
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index f08e9b8f1bc..1ee4d988caf 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -7102,6 +7102,15 @@ static void x86_cpu_set_sgxlepubkeyhash(CPUX86State *env)
#endif
}
+static bool cpuid_has_xsave_feature(CPUX86State *env, const ExtSaveArea *esa)
+{
+ if (!esa->size) {
+ return false;
+ }
+
+ return (env->features[esa->feature] & esa->bits);
+}
+
static void x86_cpu_reset_hold(Object *obj, ResetType type)
{
CPUState *cs = CPU(obj);
@@ -7210,7 +7219,7 @@ static void x86_cpu_reset_hold(Object *obj, ResetType type)
if (!((1 << i) & CPUID_XSTATE_XCR0_MASK)) {
continue;
}
- if (env->features[esa->feature] & esa->bits) {
+ if (cpuid_has_xsave_feature(env, esa)) {
xcr0 |= 1ull << i;
}
}
@@ -7348,7 +7357,7 @@ static void x86_cpu_enable_xsave_components(X86CPU *cpu)
mask = 0;
for (i = 0; i < ARRAY_SIZE(x86_ext_save_areas); i++) {
const ExtSaveArea *esa = &x86_ext_save_areas[i];
- if (env->features[esa->feature] & esa->bits) {
+ if (cpuid_has_xsave_feature(env, esa)) {
mask |= (1ULL << i);
}
}
@@ -8020,6 +8029,26 @@ static void x86_cpu_register_feature_bit_props(X86CPUClass *xcc,
static void x86_cpu_post_initfn(Object *obj)
{
+ static bool first = true;
+ uint64_t supported_xcr0;
+ int i;
+
+ if (first) {
+ first = false;
+
+ supported_xcr0 =
+ ((uint64_t) x86_cpu_get_supported_feature_word(NULL, FEAT_XSAVE_XCR0_HI) << 32) |
+ x86_cpu_get_supported_feature_word(NULL, FEAT_XSAVE_XCR0_LO);
+
+ for (i = XSTATE_SSE_BIT + 1; i < XSAVE_STATE_AREA_COUNT; i++) {
+ ExtSaveArea *esa = &x86_ext_save_areas[i];
+
+ if (!(supported_xcr0 & (1 << i))) {
+ esa->size = 0;
+ }
+ }
+ }
+
accel_cpu_instance_init(CPU(obj));
}
diff --git a/target/i386/kvm/kvm-cpu.c b/target/i386/kvm/kvm-cpu.c
index 6bf8dcfc607..d9306418490 100644
--- a/target/i386/kvm/kvm-cpu.c
+++ b/target/i386/kvm/kvm-cpu.c
@@ -133,10 +133,6 @@ static void kvm_cpu_xsave_init(void)
if (!esa->size) {
continue;
}
- if ((x86_cpu_get_supported_feature_word(NULL, esa->feature) & esa->bits)
- != esa->bits) {
- continue;
- }
host_cpuid(0xd, i, &eax, &ebx, &ecx, &edx);
if (eax != 0) {
assert(esa->size == eax);
--
2.47.0