Commit 3b9c723e authored by Wei Huang's avatar Wei Huang Committed by Paolo Bonzini
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KVM: SVM: Add support for SVM instruction address check change 



New AMD CPUs have a change that checks #VMEXIT intercept on special SVM
instructions before checking their EAX against reserved memory region.
This change is indicated by CPUID_0x8000000A_EDX[28]. If it is 1, #VMEXIT
is triggered before #GP. KVM doesn't need to intercept and emulate #GP
faults as #GP is supposed to be triggered.

Co-developed-by: default avatarBandan Das <bsd@redhat.com>
Signed-off-by: default avatarBandan Das <bsd@redhat.com>
Signed-off-by: default avatarWei Huang <wei.huang2@amd.com>
Reviewed-by: default avatarMaxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210126081831.570253-4-wei.huang2@amd.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 82a11e9c

arch/x86/include/asm/cpufeatures.h

+1 −0
Original line number Diff line number Diff line
@@ -338,6 +338,7 @@ 
#define X86_FEATURE_AVIC		(15*32+13) /* Virtual Interrupt Controller */

#define X86_FEATURE_V_VMSAVE_VMLOAD	(15*32+15) /* Virtual VMSAVE VMLOAD */

#define X86_FEATURE_VGIF		(15*32+16) /* Virtual GIF */

#define X86_FEATURE_SVME_ADDR_CHK	(15*32+28) /* "" SVME addr check */



/* Intel-defined CPU features, CPUID level 0x00000007:0 (ECX), word 16 */

#define X86_FEATURE_AVX512VBMI		(16*32+ 1) /* AVX512 Vector Bit Manipulation instructions*/

arch/x86/kvm/svm/svm.c

+3 −0
Original line number Diff line number Diff line
@@ -1040,6 +1040,9 @@ static __init int svm_hardware_setup(void) 
		}

	}



	if (boot_cpu_has(X86_FEATURE_SVME_ADDR_CHK))

		svm_gp_erratum_intercept = false;



	if (vgif) {

		if (!boot_cpu_has(X86_FEATURE_VGIF))

			vgif = false;