Re: [PATCH v5 13/19] x86/cpufeatures: Add flag to track whether MSR IA32_FEAT_CTL is configured

Jacob Keller
2020-02-26T21:53:27Z

On 2/26/2020 1:25 PM, Sean Christopherson wrote:
> Arguably, setup_pku() should be a little less heavy handed in updating
> cpufeatures for X86_FEATURE_OSPKE, but init_ia32_feat_ctl() should also be
> more robust.
>

Right.

>> But it looks like rdmsr is global and not tied to a given CPU anyways?
>

> For better or worse, the MSR is thread scoped.
>

Ahh. Definitely not obvious at a glance.

> I've reproduced the bug, should have a fix ready by EOD.
>

Nice, glad to hear it.

Thanks,
Jake