Re: [PATCH kvm-unit-tests] x86: provide enabled and disabled variation of the PCID test

[Sean Christopherson <sean.j.christopherson@intel.com>]

On Wed, Feb 05, 2020 at 06:22:05PM +0100, Andrew Jones wrote:
> On Wed, Feb 05, 2020 at 07:49:04AM -0800, Sean Christopherson wrote:
> > On Wed, Feb 05, 2020 at 04:29:40PM +0100, Paolo Bonzini wrote:
> > > The PCID test checks for exceptions when PCID=0 or INVPCID=0 in
> > > CPUID.  Cover that by adding a separate testcase with different
> > > CPUID.
> > > 
> > > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> > > ---
> > >  x86/unittests.cfg | 7 ++++++-
> > >  1 file changed, 6 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/x86/unittests.cfg b/x86/unittests.cfg
> > > index aae1523..f2401eb 100644
> > > --- a/x86/unittests.cfg
> > > +++ b/x86/unittests.cfg
> > > @@ -228,7 +228,12 @@ extra_params = --append "10000000 `date +%s`"
> > >  
> > >  [pcid]
> > >  file = pcid.flat
> > > -extra_params = -cpu qemu64,+pcid
> > > +extra_params = -cpu qemu64,+pcid,+invpcid
> > > +arch = x86_64
> > > +
> > > +[pcid-disabled]
> > > +file = pcid.flat
> > > +extra_params = -cpu qemu64,-pcid,-invpcid
> > >  arch = x86_64
> > 
> > Hrm, but "-cpu qemu64,-pcid,+invpcid" is arguably the more interesting test
> > from a KVM perspective because of the logic in KVM to hide invpcid if pcid
> > isn't supported.
> > 
> > And +pcid,-invpcid is also interesting.
> > 
> > Is there an easy-ish change that can be made to allow iterating over
> > multiple CPU configurations for single test case?
> >
> 
> Just a small change to Paolo's patch
> 
> [pcid]
> file = pcid.flat
> extra_params = -cpu qemu64,+pcid,+invpcid
> arch = x86_64
> group = pcid
> 
> [pcid-disabled]
> file = pcid.flat
> extra_params = -cpu qemu64,-pcid,-invpcid
> arch = x86_64
> group = pcid
> 
> [pcid-more-interesting]
> file = pcid.flat
> extra_params = -cpu qemu64,-pcid,+invpcid
> arch = x86_64
> group = pcid
> 
> Then run the group with ./run_tests.sh -g pcid

Ya, I was thinking more long term, e.g. syntax like:

  [pcid]
  file = pcid.flat
  permute_features = pcid,invpcid
  arch = x86_64

In general, I would love to have infrastructure to permute over *all* the
interesting bits of KVM, e.g. module params and whatnot.