KVM: X86: Report SVM bit to userspace only when supported

This patch fixes a bug in KVM where it _always_ reports the support of the SVM feature to userspace. But KVM only supports SVM on AMD hardware and only when it is enabled in the kernel module. This patch fixes the wrong reporting. Cc: [email protected] Signed-off-by: Joerg Roedel <[email protected]> Signed-off-by: Avi Kivity <[email protected]>
kyagi · Oct 24, 2010 · 4c62a2d · 4c62a2d
1 parent 3d4aeaa
commit 4c62a2d
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Showing 2 changed files with 5 additions and 1 deletion.
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
@@ -3469,6 +3469,10 @@ static void svm_cpuid_update(struct kvm_vcpu *vcpu)
 static void svm_set_supported_cpuid(u32 func, struct kvm_cpuid_entry2 *entry)
 {
 	switch (func) {
+	case 0x80000001:
+		if (nested)
+			entry->ecx |= (1 << 2); /* Set SVM bit */
+		break;
 	case 0x8000000A:
 		entry->eax = 1; /* SVM revision 1 */
 		entry->ebx = 8; /* Lets support 8 ASIDs in case we add proper

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
@@ -2209,7 +2209,7 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 		0 /* Reserved, AES */ | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX);
 	/* cpuid 0x80000001.ecx */
 	const u32 kvm_supported_word6_x86_features =
-		F(LAHF_LM) | F(CMP_LEGACY) | F(SVM) | 0 /* ExtApicSpace */ |
+		F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ |
 		F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) |
 		F(3DNOWPREFETCH) | 0 /* OSVW */ | 0 /* IBS */ | F(SSE5) |
 		0 /* SKINIT */ | 0 /* WDT */;