[Bug 216177] kvm-unit-tests vmx has about 60% of failure chance

bugzilla-daemon
2022-06-28T02:21:02Z

--- Comment #7 from Yang Lixiao (lixiao.yang@intel.com) ---
(In reply to Sean Christopherson from comment #6)
> On Tue, Jun 28, 2022, bugzilla-daemon@kernel.org wrote:
> > https://bugzilla.kernel.org/show_bug.cgi?id=216177
> >
> > --- Comment #5 from Nadav Amit (nadav.amit@gmail.com) ---
> > > On Jun 27, 2022, at 6:19 PM, bugzilla-daemon@kernel.org wrote:
> > >
> > > https://bugzilla.kernel.org/show_bug.cgi?id=216177
> > >
> > > --- Comment #3 from Yang Lixiao (lixiao.yang@intel.com) ---
> > > (In reply to Nadav Amit from comment #2)
> > >>> On Jun 27, 2022, at 5:28 PM, bugzilla-daemon@kernel.org wrote:
> > >>>
> > >>> https://bugzilla.kernel.org/show_bug.cgi?id=216177
> > >>>
> > >>> Sean Christopherson (seanjc@google.com) changed:
> > >>>
> > >>> What |Removed |Added
> > >>>
> > >>
> >
> ----------------------------------------------------------------------------
> > >>> CC| |seanjc@google.com
> > >>>
> > >>> --- Comment #1 from Sean Christopherson (seanjc@google.com) ---
> > >>> It's vmx_preemption_timer_expiry_test, which is known to be flaky
> (though
> > >>> IIRC
> > >>> it's KVM that's at fault).
> > >>>
> > >>> Test suite: vmx_preemption_timer_expiry_test
> > >>> FAIL: Last stored guest TSC (28067103426) < TSC deadline (28067086048)
> > >>
> > >> For the record:
> > >>
> > >>
> > https://lore.kernel.org/kvm/D121A03E-6861-4736-8070-5D1E4FEE1D32@gmail.com/
> > >
> > > Thanks for your reply. So this is a KVM bug, and you have sent a patch to
> > kvm
> > > to fix this bug, right?
> >
> > As I noted, at some point I did not manage to reproduce the failure.
> >
> > The failure on bare-metal that I experienced hints that this is either a
> test
> > bug or (much less likely) a hardware bug. But I do not think it is likely
> to
> > be
> > a KVM bug.
>
> Oooh, your failure was on bare-metal. I didn't grok that. Though it could
> be
> both a hardware bug and a KVM bug :-)

In my tests, I tested kvm-unit-tests vmx on bare-metal (not on VM) and this bug
happened on two different Ice Lake machines and one Cooper Lake machine.