On 27/07/2018 19:01, Sean Christopherson wrote:
> On Wed, 2018-07-18 at 13:26 -0700, Sean Christopherson wrote:
>> KVM relies on hardware to perform the "vTPR < threshold" consistency
>> check, i.e. the check will occur after KVM has done some amount of
>> guest state checking in software. As such, KVM will signal a VMExit
>> consistency check (due to bad guest state) instead of the expected
>> VMFAIL (due to bad controls).
> This analysis is wrong, the actual issue is that L1 and L2 were
> sharing an APIC access page, which was causing the vTPR check to
> pull the value from L1 instead of L2. That bug was fixed by commit
> ab5df31cee7f ("kvm: nVMX: Eliminate APIC access page sharing between
> L1 and L2"). The vTPR tests should pass with kvm/{master,next,queue}.
>
> Lucky for me, Paolo didn't queue this patch, so nothing further needs
> to be done.
>
Yep, I didn't queue it because the tests were failing and I didn't have
time to analyze it. :)
Paolo
