Page modification logging(PML) is a hardware feature designed to track guest modified memory pages. PML enables the hypervisor to identify which pages in a guest's memory have been changed since the last checkpoint or during live migration. The PML feature is advertised via CPUID leaf 0x8000000A ECX[4] bit. Acked-by: Borislav Petkov (AMD) Signed-off-by: Nikunj A Dadhania --- arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/kernel/cpu/scattered.c | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index f70ee74b5f92..cbfcc66a18e9 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -238,6 +238,7 @@ // free: was #define X86_FEATURE_PVUNLOCK ( 8*32+20) /* PV unlock function */ #define X86_FEATURE_VCPUPREEMPT ( 8*32+21) /* PV vcpu_is_preempted function */ #define X86_FEATURE_TDX_GUEST ( 8*32+22) /* "tdx_guest" Intel Trust Domain Extensions Guest */ +#define X86_FEATURE_PML ( 8*32+23) /* AMD Page Modification logging */ /* Intel-defined CPU features, CPUID level 0x00000007:0 (EBX), word 9 */ #define X86_FEATURE_FSGSBASE ( 9*32+ 0) /* "fsgsbase" RDFSBASE, WRFSBASE, RDGSBASE, WRGSBASE instructions*/ diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c index 8665a6474806..b18cc9c88dd5 100644 --- a/arch/x86/kernel/cpu/scattered.c +++ b/arch/x86/kernel/cpu/scattered.c @@ -55,6 +55,7 @@ static const struct cpuid_bit cpuid_bits[] = { { X86_FEATURE_AMD_FAST_CPPC, CPUID_EDX, 15, 0x80000007, 0 }, { X86_FEATURE_CPPC_PERF_PRIO, CPUID_EDX, 16, 0x80000007, 0 }, { X86_FEATURE_MBA, CPUID_EBX, 6, 0x80000008, 0 }, + { X86_FEATURE_PML, CPUID_ECX, 4, 0x8000000a, 0 }, { X86_FEATURE_X2AVIC_EXT, CPUID_ECX, 6, 0x8000000a, 0 }, { X86_FEATURE_COHERENCY_SFW_NO, CPUID_EBX, 31, 0x8000001f, 0 }, { X86_FEATURE_SMBA, CPUID_EBX, 2, 0x80000020, 0 }, -- 2.48.1