Commit 4c62a2dc authored by Joerg Roedel's avatar Joerg Roedel Committed by Avi Kivity
Browse files

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: stable@kernel.org
Signed-off-by: default avatarJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent 3d4aeaad

arch/x86/kvm/svm.c

+4 −0
Original line number Diff line number Diff line
@@ -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

arch/x86/kvm/x86.c

+1 −1
Original line number Diff line number Diff line
@@ -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 */;

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