Re: [PATCH 1/7] x86/feature: Detect the x86 feature to control Speculation

Thomas Gleixner
2018-01-05T13:09:50Z

On Thu, 4 Jan 2018, Tim Chen wrote:
> +#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 MSR_IA32_PERFCTR0 0x000000c1
> #define MSR_IA32_PERFCTR1 0x000000c2
> #define MSR_FSB_FREQ 0x000000cd
> @@ -439,6 +445,7 @@
> #define FEATURE_CONTROL_VMXON_ENABLED_INSIDE_SMX (1<<1)
> #define FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX (1<<2)
> #define FEATURE_CONTROL_LMCE (1<<20)
> +#define FEATURE_SET_IBPB (1<<0)

So how is that bit related to the control bits above? This file is
structured in obvious ways ....

Thanks,

tglx