Re: [PATCH] nVMX: Keep arch.pat in sync on L1-L2 switches

[Gleb Natapov <gleb@redhat.com>]

On Sun, Aug 04, 2013 at 05:17:27PM +0200, Jan Kiszka wrote:
> From: Jan Kiszka <jan.kiszka@siemens.com>
> 
> When asking vmx to load the PAT MSR for us while switching from L1 to L2
> or vice versa, we have to update arch.pat as well as it may later be
> used again to load or read out the MSR content.
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Gleb Natapov <gleb@redhat.com>

> ---
> 
> Arthur, please add your tested-by also officially.
> 
>  arch/x86/kvm/vmx.c |    9 ++++++---
>  1 files changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index 45fd70c..396572d 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -7535,9 +7535,10 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
>  	vmcs_write32(VM_ENTRY_CONTROLS, vmcs12->vm_entry_controls |
>  		(vmcs_config.vmentry_ctrl & ~VM_ENTRY_IA32E_MODE));
>  
> -	if (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_IA32_PAT)
> +	if (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_IA32_PAT) {
>  		vmcs_write64(GUEST_IA32_PAT, vmcs12->guest_ia32_pat);
> -	else if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT)
> +		vcpu->arch.pat = vmcs12->guest_ia32_pat;
> +	} else if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT)
>  		vmcs_write64(GUEST_IA32_PAT, vmx->vcpu.arch.pat);
>  
>  
> @@ -8025,8 +8026,10 @@ static void load_vmcs12_host_state(struct kvm_vcpu *vcpu,
>  	vmcs_writel(GUEST_IDTR_BASE, vmcs12->host_idtr_base);
>  	vmcs_writel(GUEST_GDTR_BASE, vmcs12->host_gdtr_base);
>  
> -	if (vmcs12->vm_exit_controls & VM_EXIT_LOAD_IA32_PAT)
> +	if (vmcs12->vm_exit_controls & VM_EXIT_LOAD_IA32_PAT) {
>  		vmcs_write64(GUEST_IA32_PAT, vmcs12->host_ia32_pat);
> +		vcpu->arch.pat = vmcs12->host_ia32_pat;
> +	}
>  	if (vmcs12->vm_exit_controls & VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL)
>  		vmcs_write64(GUEST_IA32_PERF_GLOBAL_CTRL,
>  			vmcs12->host_ia32_perf_global_ctrl);
> -- 
> 1.7.3.4

--
			Gleb.