These MSRs are available if the CPU features SPEC_CTRL (CPUID(EAX=7,ECX=0).EDX[26]) is present. The PRED_CMD MSR is also available if the CPU feature IBPB_SUPPORT (CPUID(EAX=0x80000008).EBX[12]) is present.
KVM will soon start using PRED_CMD and will make SPEC_CTRL available to guests. Reviewed-by: Liran Alon <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]> --- arch/x86/include/asm/msr-index.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index 03ffde6217d0..828a03425571 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -464,8 +464,15 @@ #define MSR_SMI_COUNT 0x00000034 #define MSR_IA32_FEATURE_CONTROL 0x0000003a #define MSR_IA32_TSC_ADJUST 0x0000003b -#define MSR_IA32_BNDCFGS 0x00000d90 +#define MSR_IA32_SPEC_CTRL 0x00000048 +#define SPEC_CTRL_FEATURE_DISABLE_IBRS (0 << 0) +#define SPEC_CTRL_FEATURE_ENABLE_IBRS (1 << 0) + +#define MSR_IA32_PRED_CMD 0x00000049 +#define PRED_CMD_IBPB (1UL << 0) + +#define MSR_IA32_BNDCFGS 0x00000d90 #define MSR_IA32_BNDCFGS_RSVD 0x00000ffc #define MSR_IA32_XSS 0x00000da0 -- 1.8.3.1
