When AMD introduced "Long Mode Segment Limit Enable" (a.k.a. "VMware mode"), the feature was not enumerated by a CPUID bit. Now that VMware has abandoned binary translation, AMD has deprecated EFER.LMSLE. The absence of the feature *is* now enumerated by a CPUID bit (a la Intel's X86_FEATURE_ZERO_FCS_DCS and X86_FEATURE_FDP_EXCPTN_ONLY). This defeature bit is already present in feature word 13, but it was previously anonymous. Name it X86_FEATURE_NO_LMSLE, so that KVM can reference it when deciding whether or not EFER.LMSLE should be a reserved bit in a KVM guest. Since this bit indicates the absence of a feature, don't enumerate it in /proc/cpuinfo. Signed-off-by: Jim Mattson <jmattson@xxxxxxxxxx> --- arch/x86/include/asm/cpufeatures.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index ef4775c6db01..0f5a3285d8d8 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -319,6 +319,7 @@ #define X86_FEATURE_AMD_IBRS (13*32+14) /* "" Indirect Branch Restricted Speculation */ #define X86_FEATURE_AMD_STIBP (13*32+15) /* "" Single Thread Indirect Branch Predictors */ #define X86_FEATURE_AMD_STIBP_ALWAYS_ON (13*32+17) /* "" Single Thread Indirect Branch Predictors always-on preferred */ +#define X86_FEATURE_NO_LMSLE (13*32+20) /* "" EFER_LMSLE is unsupported */ #define X86_FEATURE_AMD_PPIN (13*32+23) /* Protected Processor Inventory Number */ #define X86_FEATURE_AMD_SSBD (13*32+24) /* "" Speculative Store Bypass Disable */ #define X86_FEATURE_VIRT_SSBD (13*32+25) /* Virtualized Speculative Store Bypass Disable */ -- 2.37.3.968.ga6b4b080e4-goog
