From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: KVM: VMX: remove GUEST_CR3 write from vmx_vcpu_run
Date: Tue, 20 Oct 2009 22:14:52 +0900
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Cc: kvm <kvm@vger.kernel.org>
To: Marcelo Tosatti <mtosatti@redhat.com>
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On 10/20/2009 09:37 PM, Marcelo Tosatti wrote:
> GUEST_CR3 is updated via kvm_set_cr3 whenever CR3 value
> changes.
>
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index 364263a..325075f 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -3638,10 +3638,9 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu)
>   {
>   	struct vcpu_vmx *vmx = to_vmx(vcpu);
>
> -	if (enable_ept&&  is_paging(vcpu)) {
> -		vmcs_writel(GUEST_CR3, vcpu->arch.cr3);
> +	if (enable_ept&&  is_paging(vcpu))
>   		ept_load_pdptrs(vcpu);
> -	}
> +
>   	/* Record the guest's net vcpu time for enforced NMI injections. */
>   	if (unlikely(!cpu_has_virtual_nmis()&&  vmx->soft_vnmi_blocked))
>   		vmx->entry_time = ktime_get();
>    

Nice.  Any reason why ept_load_pdptrs() couldn't go the same way?

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.