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Date:   Thu, 14 Oct 2021 18:50:58 +0000
From:   Sean Christopherson <seanjc@google.com>
To:     Lai Jiangshan <jiangshanlai@gmail.com>
Cc:     linux-kernel@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>, kvm@vger.kernel.org,
        Lai Jiangshan <laijs@linux.alibaba.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH 2/2] KVM: X86: Don't reset mmu context when toggling
 X86_CR4_PGE
Message-ID: <YWh8EndpDdHYX7aY@google.com>
References: <20210919024246.89230-1-jiangshanlai@gmail.com>
 <20210919024246.89230-3-jiangshanlai@gmail.com>
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On Sun, Sep 19, 2021, Lai Jiangshan wrote:
> From: Lai Jiangshan <laijs@linux.alibaba.com>
> 
> X86_CR4_PGE doesn't participate in kvm_mmu_role, so the mmu context
> doesn't need to be reset.  It is only required to flush all the guest
> tlb.
> 
> It is also inconsistent that X86_CR4_PGE is in KVM_MMU_CR4_ROLE_BITS
> while kvm_mmu_role doesn't use X86_CR4_PGE.  So X86_CR4_PGE is also
> removed from KVM_MMU_CR4_ROLE_BITS.
> 
> Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
> ---

With the KVM_REQ_TLB_FLUSH_GUEST caveat, 

Reviewed-by: Sean Christopherson <seanjc@google.com>