Re: [PATCH 0/2] KVM: x86: Rep string I/O WARN removal and test

From: Sean Christopherson
Date: Thu Dec 09 2021 - 10:50:14 EST


On Thu, Dec 09, 2021, Paolo Bonzini wrote:
> On 12/9/21 06:48, Sean Christopherson wrote:
> > On Mon, Oct 25, 2021, Sean Christopherson wrote:
> > > Remove a WARN that was added as part of the recent I/O overhaul to play
> > > nice with SEV-ES string I/O.
> > >
> > > For the record, my FIXME in lieu of a WARN was deliberate, as I suspected
> > > userspace could trigger a WARN ;-)
> > >
> > > Based on kvm/master, commit 95e16b4792b0 ("KVM: SEV-ES: go over the
> > > sev_pio_data buffer in multiple passes if needed").
> > >
> > > Sean Christopherson (2):
> > > KVM: x86: Don't WARN if userspace mucks with RCX during string I/O
> > > exit
> > > KVM: selftests: Add test to verify KVM doesn't explode on "bad" I/O
> > >
> > > arch/x86/kvm/x86.c | 9 +-
> > > tools/testing/selftests/kvm/.gitignore | 1 +
> > > tools/testing/selftests/kvm/Makefile | 1 +
> > > .../selftests/kvm/x86_64/userspace_io_test.c | 114 ++++++++++++++++++
> > > 4 files changed, 123 insertions(+), 2 deletions(-)
> > > create mode 100644 tools/testing/selftests/kvm/x86_64/userspace_io_test.c
> >
> > Ping. I completely forgot about this too, until I unintentionally ran a
> > userspace_io_test that was lying around.
> >
>
> Queued now, thanks. I don't know if I want the honor of having KVM singled
> out again on the -rc release message, but these are bugs nevertheless...

Heh, you could always wait an -rc to send the fixes and hope Linus has a short
memory :-D