Commit faabfcb1 authored by Kim Phillips's avatar Kim Phillips Committed by Borislav Petkov (AMD)
Browse files

x86/cpu, kvm: Add the SMM_CTL MSR not present feature 



The SMM_CTL MSR not present feature was being open-coded for KVM.
Add it to its newly added CPUID leaf 0x80000021 EAX proper.

Also drop the bit description comments now the code is more
self-describing.

Signed-off-by: default avatarKim Phillips <kim.phillips@amd.com>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Acked-by: default avatarSean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20230124163319.2277355-7-kim.phillips@amd.com
parent 5b909d4a

arch/x86/include/asm/cpufeatures.h

+1 −0
Original line number Diff line number Diff line
@@ -431,6 +431,7 @@ 
#define X86_FEATURE_NO_NESTED_DATA_BP	(20*32+ 0) /* "" No Nested Data Breakpoints */

#define X86_FEATURE_LFENCE_RDTSC	(20*32+ 2) /* "" LFENCE always serializing / synchronizes RDTSC */

#define X86_FEATURE_NULL_SEL_CLR_BASE	(20*32+ 6) /* "" Null Selector Clears Base */

#define X86_FEATURE_NO_SMM_CTL_MSR	(20*32+ 9) /* "" SMM_CTL MSR is not present */



/*

 * BUG word(s)

arch/x86/kvm/cpuid.c

+1 −1
Original line number Diff line number Diff line
@@ -760,7 +760,7 @@ void kvm_set_cpu_caps(void) 
		kvm_cpu_cap_set(X86_FEATURE_LFENCE_RDTSC);

	if (!static_cpu_has_bug(X86_BUG_NULL_SEG))

		kvm_cpu_cap_set(X86_FEATURE_NULL_SEL_CLR_BASE);

	kvm_cpu_caps[CPUID_8000_0021_EAX] |= BIT(9) /* NO_SMM_CTL_MSR */;

	kvm_cpu_cap_set(X86_FEATURE_NO_SMM_CTL_MSR);



	kvm_cpu_cap_mask(CPUID_C000_0001_EDX,

		F(XSTORE) | F(XSTORE_EN) | F(XCRYPT) | F(XCRYPT_EN) |