Re: [PATCH] KVM: x86: Reset MMU context if guest toggles CR4.SMAP or CR4.PKE

From: Jim Mattson
Date: Thu Sep 24 2020 - 17:48:25 EST


On Wed, Sep 23, 2020 at 2:54 PM Sean Christopherson
<sean.j.christopherson@xxxxxxxxx> wrote:
>
> Reset the MMU context during kvm_set_cr4() if SMAP or PKE is toggled.
> Recent commits to (correctly) not reload PDPTRs when SMAP/PKE are
> toggled inadvertantly skipped the MMU context reset due to the mask
> of bits that triggers PDPTR loads also being used to trigger MMU context
> resets.
>
> Fixes: 427890aff855 ("kvm: x86: Toggling CR4.SMAP does not load PDPTEs in PAE mode")
> Fixes: cb957adb4ea4 ("kvm: x86: Toggling CR4.PKE does not load PDPTEs in PAE mode")
> Cc: Jim Mattson <jmattson@xxxxxxxxxx>
> Cc: Peter Shier <pshier@xxxxxxxxxx>
> Cc: Oliver Upton <oupton@xxxxxxxxxx>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>

Thanks for the fix!

Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>