On Mon, Nov 26, 2018 at 01:08:31PM -0800, Jim Mattson wrote:
> On Wed, May 30, 2018 at 11:55 AM Jim Mattson <jmattson@xxxxxxxxxx> wrote:
> >
> > Hi Konrad,
> >
> > I don't expect any hypervisor to do this, but I'll see if I can put
> > together a unit test.
Thank you for doing the test-case.
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
.. and sorry for the delay.
> >
> > On Wed, May 30, 2018 at 11:19 AM, Konrad Rzeszutek Wilk
> > <konrad.wilk@xxxxxxxxxx> wrote:
> > > 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
> > >>
>
> Ping.
