On 16/01/2020 22:16, speck for mark gross wrote:
> +static void __init srbds_select_mitigation(void)
> +{
> +	u64 ia32_cap;
> +
> +	if (!boot_cpu_has_bug(X86_BUG_SRBDS)) {
> +		srbds_mitigation = SRBDS_NOT_AFFECTED;
> +		return;
> +	}
> +
> +	if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
> +		srbds_mitigation = SRBDS_HYPERVISOR;
> +		return;
> +	}

These two ought to be reversing (and with a suitable adjustment to the
docs in patch 2).

If you're running as a guest, you can't even trust the model number used
to divine X86_BUG_SRBDS in the first place.

~Andrew