On Wed, May 30, 2018 at 11:10:50AM -0700, Jim Mattson wrote:
> It is never correct for a VMX instruction to fail with "invalid VMCS"
> if there is, in fact, a current VMCS. Reads from unbacked addresses
> return all 1's, which means that an unbacked VMCS will not have the
> correct VMCS revision ID.
Yikes.
Is there a particular Hypervisor that does this? Would it make sense
to also have some kiund of test-cases?
>
> Signed-off-by: Jim Mattson <jmattson@xxxxxxxxxx>
> ---
> arch/x86/kvm/vmx.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index e50beb76d846..705a5afe5374 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -8348,7 +8348,8 @@ static int handle_vmptrld(struct kvm_vcpu *vcpu)
> struct page *page;
> page = kvm_vcpu_gpa_to_page(vcpu, vmptr);
> if (is_error_page(page)) {
> - nested_vmx_failInvalid(vcpu);
> + nested_vmx_failValid(vcpu,
> + VMXERR_VMPTRLD_INCORRECT_VMCS_REVISION_ID);
> return kvm_skip_emulated_instruction(vcpu);
> }
> new_vmcs12 = kmap(page);
> --
> 2.17.0.921.gf22659ad46-goog
>
