Instead of getting an exact leaf, follow the spec and fall back to the last
main leaf instead. This lets us easily emulate the cpuid instruction in the
emulator.
Signed-off-by: Avi Kivity <avi@xxxxxxxxxx>
---
arch/x86/include/asm/kvm_emulate.h | 4 +--
arch/x86/kvm/emulate.c | 53 ++++++++++++++++++------------------
arch/x86/kvm/x86.c | 20 ++------------
3 files changed, 30 insertions(+), 47 deletions(-)
diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h
index 1ac46c22..cd5c96b 100644
--- a/arch/x86/include/asm/kvm_emulate.h
+++ b/arch/x86/include/asm/kvm_emulate.h
@@ -192,8 +192,8 @@ struct x86_emulate_ops {
struct x86_instruction_info *info,
enum x86_intercept_stage stage);
- bool (*get_cpuid)(struct x86_emulate_ctxt *ctxt,
- u32 *eax, u32 *ebx, u32 *ecx, u32 *edx);
+ void (*get_cpuid)(struct x86_emulate_ctxt *ctxt,
+ u32 *eax, u32 *ebx, u32 *ecx, u32 *edx);
};
typedef u32 __attribute__((vector_size(16))) sse128_t;
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index f95d242..ba1f8ec 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1993,8 +1993,8 @@ static bool vendor_intel(struct x86_emulate_ctxt *ctxt)
u32 eax, ebx, ecx, edx;
eax = ecx = 0;
- return ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx)
- && ebx == X86EMUL_CPUID_VENDOR_GenuineIntel_ebx
+ ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx);
+ return ebx == X86EMUL_CPUID_VENDOR_GenuineIntel_ebx
&& ecx == X86EMUL_CPUID_VENDOR_GenuineIntel_ecx
&& edx == X86EMUL_CPUID_VENDOR_GenuineIntel_edx;
}
@@ -2013,32 +2013,31 @@ static bool em_syscall_is_enabled(struct x86_emulate_ctxt *ctxt)
eax = 0x00000000;
ecx = 0x00000000;
- if (ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx)) {
- /*
- * Intel ("GenuineIntel")
- * remark: Intel CPUs only support "syscall" in 64bit
- * longmode. Also an 64bit guest with a
- * 32bit compat-app running will #UD !! While this
- * behaviour can be fixed (by emulating) into AMD
- * response - CPUs of AMD can't behave like Intel.
- */
- if (ebx == X86EMUL_CPUID_VENDOR_GenuineIntel_ebx &&
- ecx == X86EMUL_CPUID_VENDOR_GenuineIntel_ecx &&
- edx == X86EMUL_CPUID_VENDOR_GenuineIntel_edx)
- return false;
+ ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx);
+ /*
+ * Intel ("GenuineIntel")
+ * remark: Intel CPUs only support "syscall" in 64bit
+ * longmode. Also an 64bit guest with a
+ * 32bit compat-app running will #UD !! While this
+ * behaviour can be fixed (by emulating) into AMD
+ * response - CPUs of AMD can't behave like Intel.
+ */
+ if (ebx == X86EMUL_CPUID_VENDOR_GenuineIntel_ebx &&
+ ecx == X86EMUL_CPUID_VENDOR_GenuineIntel_ecx &&
+ edx == X86EMUL_CPUID_VENDOR_GenuineIntel_edx)
+ return false;
- /* AMD ("AuthenticAMD") */
- if (ebx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ebx &&
- ecx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ecx &&
- edx == X86EMUL_CPUID_VENDOR_AuthenticAMD_edx)
- return true;
-
- /* AMD ("AMDisbetter!") */
- if (ebx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ebx &&
- ecx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ecx &&
- edx == X86EMUL_CPUID_VENDOR_AMDisbetterI_edx)
- return true;
- }
+ /* AMD ("AuthenticAMD") */
+ if (ebx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ebx &&
+ ecx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ecx &&
+ edx == X86EMUL_CPUID_VENDOR_AuthenticAMD_edx)
+ return true;
+
+ /* AMD ("AMDisbetter!") */
+ if (ebx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ebx &&
+ ecx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ecx &&
+ edx == X86EMUL_CPUID_VENDOR_AMDisbetterI_edx)
+ return true;
/* default: (not Intel, not AMD), apply Intel's stricter rules... */
return false;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a01a424..016cec5 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4297,26 +4297,10 @@ static int emulator_intercept(struct x86_emulate_ctxt *ctxt,
return kvm_x86_ops->check_intercept(emul_to_vcpu(ctxt), info, stage);
}
-static bool emulator_get_cpuid(struct x86_emulate_ctxt *ctxt,
+static void emulator_get_cpuid(struct x86_emulate_ctxt *ctxt,
u32 *eax, u32 *ebx, u32 *ecx, u32 *edx)
{
- struct kvm_cpuid_entry2 *cpuid = NULL;
-
- if (eax && ecx)
- cpuid = kvm_find_cpuid_entry(emul_to_vcpu(ctxt),
- *eax, *ecx);
-
- if (cpuid) {
- *eax = cpuid->eax;
- *ecx = cpuid->ecx;
- if (ebx)
- *ebx = cpuid->ebx;
- if (edx)
- *edx = cpuid->edx;
- return true;
- }
-
- return false;
+ kvm_cpuid(emul_to_vcpu(ctxt), eax, ebx, ecx, edx);
}
static struct x86_emulate_ops emulate_ops = {
--
1.7.10.1
--
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