summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--target-i386/helper.c46
1 files changed, 31 insertions, 15 deletions
diff --git a/target-i386/helper.c b/target-i386/helper.c
index 957b3fc1f..08e6d6c39 100644
--- a/target-i386/helper.c
+++ b/target-i386/helper.c
@@ -1638,6 +1638,24 @@ static void host_cpuid(uint32_t function, uint32_t count,
#endif
}
+static void get_cpuid_vendor(CPUX86State *env, uint32_t *ebx,
+ uint32_t *ecx, uint32_t *edx)
+{
+ *ebx = env->cpuid_vendor1;
+ *edx = env->cpuid_vendor2;
+ *ecx = env->cpuid_vendor3;
+
+ /* sysenter isn't supported on compatibility mode on AMD, syscall
+ * isn't supported in compatibility mode on Intel.
+ * Normally we advertise the actual cpu vendor, but you can override
+ * this if you want to use KVM's sysenter/syscall emulation
+ * in compatibility mode and when doing cross vendor migration
+ */
+ if (kvm_enabled() && env->cpuid_vendor_override) {
+ host_cpuid(0, 0, NULL, ebx, ecx, edx);
+ }
+}
+
void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
uint32_t *eax, uint32_t *ebx,
uint32_t *ecx, uint32_t *edx)
@@ -1654,16 +1672,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
switch(index) {
case 0:
*eax = env->cpuid_level;
- *ebx = env->cpuid_vendor1;
- *edx = env->cpuid_vendor2;
- *ecx = env->cpuid_vendor3;
-
- /* sysenter isn't supported on compatibility mode on AMD. and syscall
- * isn't supported in compatibility mode on Intel. so advertise the
- * actuall cpu, and say goodbye to migration between different vendors
- * is you use compatibility mode. */
- if (kvm_enabled() && !env->cpuid_vendor_override)
- host_cpuid(0, 0, NULL, ebx, ecx, edx);
+ get_cpuid_vendor(env, ebx, ecx, edx);
break;
case 1:
*eax = env->cpuid_version;
@@ -1759,11 +1768,18 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
*ecx = env->cpuid_ext3_features;
*edx = env->cpuid_ext2_features;
- if (env->nr_cores * env->nr_threads > 1 &&
- env->cpuid_vendor1 == CPUID_VENDOR_AMD_1 &&
- env->cpuid_vendor2 == CPUID_VENDOR_AMD_2 &&
- env->cpuid_vendor3 == CPUID_VENDOR_AMD_3) {
- *ecx |= 1 << 1; /* CmpLegacy bit */
+ /* The Linux kernel checks for the CMPLegacy bit and
+ * discards multiple thread information if it is set.
+ * So dont set it here for Intel to make Linux guests happy.
+ */
+ if (env->nr_cores * env->nr_threads > 1) {
+ uint32_t tebx, tecx, tedx;
+ get_cpuid_vendor(env, &tebx, &tecx, &tedx);
+ if (tebx != CPUID_VENDOR_INTEL_1 ||
+ tedx != CPUID_VENDOR_INTEL_2 ||
+ tecx != CPUID_VENDOR_INTEL_3) {
+ *ecx |= 1 << 1; /* CmpLegacy bit */
+ }
}
if (kvm_enabled()) {