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

Gleb Natapov
2013-08-05T08:40:16Z

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.