Re: KVM: VMX: move CR3/PDPTR update to vmx_set_cr3

["Yang, Sheng" <sheng.yang@intel.com>]

On Tuesday 27 October 2009 02:48:33 Marcelo Tosatti wrote:
> GUEST_CR3 is updated via kvm_set_cr3 whenever CR3 is modified from
> outside guest context. Similarly pdptrs are updated via load_pdptrs.
>
> Let kvm_set_cr3 perform the update, removing it from the vcpu_run
> fast path.

Looks fine to me.

Acked-by: Sheng Yang <sheng@linux.intel.com>

-- 
regards
Yang, Sheng
>
> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
>
> Index: b/arch/x86/kvm/vmx.c
> ===================================================================
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -1748,6 +1748,7 @@ static void vmx_set_cr3(struct kvm_vcpu
>  		vmcs_write64(EPT_POINTER, eptp);
>  		guest_cr3 = is_paging(vcpu) ? vcpu->arch.cr3 :
>  			vcpu->kvm->arch.ept_identity_map_addr;
> +		ept_load_pdptrs(vcpu);
>  	}
>
>  	vmx_flush_tlb(vcpu);
> @@ -3638,10 +3639,6 @@ static void vmx_vcpu_run(struct kvm_vcpu
>  {
>  	struct vcpu_vmx *vmx = to_vmx(vcpu);
>
> -	if (enable_ept && is_paging(vcpu)) {
> -		vmcs_writel(GUEST_CR3, vcpu->arch.cr3);
> -		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();
> Index: b/arch/x86/kvm/x86.c
> ===================================================================
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -4517,8 +4517,10 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct
>
>  	mmu_reset_needed |= vcpu->arch.cr4 != sregs->cr4;
>  	kvm_x86_ops->set_cr4(vcpu, sregs->cr4);
> -	if (!is_long_mode(vcpu) && is_pae(vcpu))
> +	if (!is_long_mode(vcpu) && is_pae(vcpu)) {
>  		load_pdptrs(vcpu, vcpu->arch.cr3);
> +		mmu_reset_needed = 1;
> +	}
>
>  	if (mmu_reset_needed)
>  		kvm_mmu_reset_context(vcpu);