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Date:   Mon, 10 Apr 2023 16:30:17 -0700
In-Reply-To: <20230405002608.418442-1-seanjc@google.com>
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Subject: Re: [PATCH] KVM: x86/mmu: Refresh CR0.WP prior to checking for
 emulated permission faults
From:   Sean Christopherson <seanjc@google.com>
To:     Sean Christopherson <seanjc@google.com>,
        Paolo Bonzini <pbonzini@redhat.com>
Cc:     kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        Mathias Krause <minipli@grsecurity.net>
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On Tue, 04 Apr 2023 17:26:08 -0700, Sean Christopherson wrote:
> If CR0.WP may be guest-owned, i.e. TDP is enabled, refresh the MMU's
> snapshot of the guest's CR0.WP prior to checking for permission faults
> when emulating a guest memory access.  If the guest toggles only CR0.WP
> and triggers emulation of a supervisor write, e.g. when KVM is emulating
> UMIP, KVM may consume a stale CR0.WP, i.e. use stale protection bits
> metadata.
> 
> [...]

Applied to kvm-x86 misc, with a reworked changelog.

[1/1] KVM: x86/mmu: Refresh CR0.WP prior to checking for emulated permission faults
      https://github.com/kvm-x86/linux/commit/cf9f4c0eb169

--
https://github.com/kvm-x86/linux/tree/next
https://github.com/kvm-x86/linux/tree/fixes