Re: [PATCH] KVM/nSVM: properly map nested VMCB

From: Paolo Bonzini
Date: Tue Jun 04 2019 - 13:31:03 EST


On 04/06/19 18:09, Vitaly Kuznetsov wrote:
> Commit 8c5fbf1a7231 ("KVM/nSVM: Use the new mapping API for mapping guest
> memory") broke nested SVM completely: kvm_vcpu_map()'s second parameter is
> GFN so vmcb_gpa needs to be converted with gpa_to_gfn(), not the other way
> around.
>
> Fixes: 8c5fbf1a7231 ("KVM/nSVM: Use the new mapping API for mapping guest memory")
> Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
> ---
> arch/x86/kvm/svm.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index 735b8c01895e..5beca1030c9a 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -3293,7 +3293,7 @@ static int nested_svm_vmexit(struct vcpu_svm *svm)
> vmcb->control.exit_int_info_err,
> KVM_ISA_SVM);
>
> - rc = kvm_vcpu_map(&svm->vcpu, gfn_to_gpa(svm->nested.vmcb), &map);
> + rc = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(svm->nested.vmcb), &map);
> if (rc) {
> if (rc == -EINVAL)
> kvm_inject_gp(&svm->vcpu, 0);
> @@ -3583,7 +3583,7 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
>
> vmcb_gpa = svm->vmcb->save.rax;
>
> - rc = kvm_vcpu_map(&svm->vcpu, gfn_to_gpa(vmcb_gpa), &map);
> + rc = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(vmcb_gpa), &map);
> if (rc) {
> if (rc == -EINVAL)
> kvm_inject_gp(&svm->vcpu, 0);
>

Oops. Queued, thanks.

Paolo