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Subject: Re: [PATCH v5 13/19] x86/cpufeatures: Add flag to track whether MSR
 IA32_FEAT_CTL is configured
To:     Sean Christopherson <sean.j.christopherson@intel.com>
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From:   Jacob Keller <jacob.e.keller@intel.com>
Organization: Intel Corporation
Message-ID: <5f480e36-f6ed-e72d-2e18-96617b37958e@intel.com>
Date:   Wed, 26 Feb 2020 13:53:21 -0800
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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