Re: [kvm-unit-tests GIT PULL] x86: random smattering of changes

[Sean Christopherson <seanjc@google.com>]

On Thu, May 28, 2026, Yosry Ahmed wrote:
> On Thu, May 28, 2026 at 12:07 PM Sean Christopherson <seanjc@google.com> wrote:
> >
> > On Wed, May 27, 2026, Yosry Ahmed wrote:
> > > > > ----------------------------------------------------------------
> > > > > Isaku Yamahata (2):
> > > > >       x86: Replace NOP with CPUID after WRMSR(TSCDEADLINE) to serialize deadline timer
> > > > >       x86: tscdeadline_latency: Remove unnecessary nop
> > > > >
> > > > > Jim Mattson (1):
> > > > >       x86: nVMX: Add retry loop to advanced RTM debugging subtest
> > > > >
> > > > > Kevin Cheng (2):
> > > > >       x86/svm: Add missing svm intercepts
> > > > >       x86/svm: Add unsupported instruction intercept test
> > > >
> > > > Any reason not to include this series:
> > > > https://lore.kernel.org/kvm/20260312200308.3089379-1-chengkev@google.com/?
> >
> > I ran out of steam (and time), and I don't want to merge like this without a high
> > level of confidence that it's the least awful option.
> 
> We're already doing this for vmx:
> https://gitlab.com/kvm-unit-tests/kvm-unit-tests/-/blob/master/x86/vmx_tests.c?ref_type=heads#L806.
> 
> If this is the only thing holding that series, I think cleaning it up
> should be done separately for both VMX and SVM.

I don't buy that argument.  Taking it to the extreme, that's like saying it's ok
to use bare "unsigned" because there exists such code in the kernel.  It's very
difficult to make progress if we don't raise the bar.

I'm not saying "no" to the series, nor am saying you (or Kevin) needs to clean
up the nVMX code in order to land the nSVM code.  I'm simply explaining why I
didn't grab the series: it's got some fugly code I want to look at more closely,
but I ran out of time and brainpower.