Re: [PATCH 0/3] KVM: x86: Fix fault-related bugs in LTR/LLDT emulation

From: Sean Christopherson
Date: Thu Jul 14 2022 - 14:21:32 EST


On Mon, Jul 11, 2022, Nadav Amit wrote:
> On Jul 11, 2022, at 4:27 PM, Sean Christopherson <seanjc@xxxxxxxxxx> wrote:
>
> > Patch 1 fixes a bug found by syzkaller where KVM attempts to set the
> > TSS.busy bit during LTR before checking that the new TSS.base is valid.
> >
> > Patch 2 fixes a bug found by inspection (when reading the APM to verify
> > the non-canonical logic is correct) where KVM doesn't provide the correct
> > error code if the new TSS.base is non-canonical.
> >
> > Patch 3 makes the "dangling userspace I/O" WARN_ON two separate WARN_ON_ONCE
> > so that a KVM bug doesn't spam the kernel log (keeping the WARN is desirable
> > specifically to detect these types of bugs).
>
> Hi Sean,
>
> If/when you find that I screwed up, would you be kind enough to cc me?

Will do!

> Very likely I won’t be able to assist too much in fixing the bugs under my
> current affiliation, but it is always interesting to see the escapees of
> Intel’s validation tools… ;-)
>
> Only if you can.
>
> Thanks,
> Nadav
>
> [ p.s. - please use my gmail account for the matter ]

Yep, still got an alias for ya :-)