Enumerate Linear Address Masking and provide defines for CR3 and CR4 flags. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Reviewed-by: Alexander Potapenko <glider@xxxxxxxxxx> Tested-by: Alexander Potapenko <glider@xxxxxxxxxx> Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> --- arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/include/asm/processor-flags.h | 2 ++ arch/x86/include/uapi/asm/processor-flags.h | 6 ++++++ 3 files changed, 9 insertions(+) diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index 235dc85c91c3..73c0cf5bd8a1 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -308,6 +308,7 @@ /* Intel-defined CPU features, CPUID level 0x00000007:1 (EAX), word 12 */ #define X86_FEATURE_AVX_VNNI (12*32+ 4) /* AVX VNNI instructions */ #define X86_FEATURE_AVX512_BF16 (12*32+ 5) /* AVX512 BFLOAT16 instructions */ +#define X86_FEATURE_LAM (12*32+26) /* Linear Address Masking */ /* AMD-defined CPU features, CPUID level 0x80000008 (EBX), word 13 */ #define X86_FEATURE_CLZERO (13*32+ 0) /* CLZERO instruction */ diff --git a/arch/x86/include/asm/processor-flags.h b/arch/x86/include/asm/processor-flags.h index a7f3d9100adb..d8cccadc83a6 100644 --- a/arch/x86/include/asm/processor-flags.h +++ b/arch/x86/include/asm/processor-flags.h @@ -28,6 +28,8 @@ * On systems with SME, one bit (in a variable position!) is stolen to indicate * that the top-level paging structure is encrypted. * + * On systemms with LAM, bits 61 and 62 are used to indicate LAM mode. + * * All of the remaining bits indicate the physical address of the top-level * paging structure. * diff --git a/arch/x86/include/uapi/asm/processor-flags.h b/arch/x86/include/uapi/asm/processor-flags.h index c47cc7f2feeb..d898432947ff 100644 --- a/arch/x86/include/uapi/asm/processor-flags.h +++ b/arch/x86/include/uapi/asm/processor-flags.h @@ -82,6 +82,10 @@ #define X86_CR3_PCID_BITS 12 #define X86_CR3_PCID_MASK (_AC((1UL << X86_CR3_PCID_BITS) - 1, UL)) +#define X86_CR3_LAM_U57_BIT 61 /* Activate LAM for userspace, 62:57 bits masked */ +#define X86_CR3_LAM_U57 _BITULL(X86_CR3_LAM_U57_BIT) +#define X86_CR3_LAM_U48_BIT 62 /* Activate LAM for userspace, 62:48 bits masked */ +#define X86_CR3_LAM_U48 _BITULL(X86_CR3_LAM_U48_BIT) #define X86_CR3_PCID_NOFLUSH_BIT 63 /* Preserve old PCID */ #define X86_CR3_PCID_NOFLUSH _BITULL(X86_CR3_PCID_NOFLUSH_BIT) @@ -132,6 +136,8 @@ #define X86_CR4_PKE _BITUL(X86_CR4_PKE_BIT) #define X86_CR4_CET_BIT 23 /* enable Control-flow Enforcement Technology */ #define X86_CR4_CET _BITUL(X86_CR4_CET_BIT) +#define X86_CR4_LAM_SUP_BIT 28 /* LAM for supervisor pointers */ +#define X86_CR4_LAM_SUP _BITUL(X86_CR4_LAM_SUP_BIT) /* * x86-64 Task Priority Register, CR8 -- 2.35.1