Re: linux-next: build warning after merge of the kvm tree

From: Sean Christopherson
Date: Wed Nov 13 2024 - 09:11:37 EST


On Wed, Nov 13, 2024, Stephen Rothwell wrote:
> Hi all,
>
> On Mon, 28 Oct 2024 19:29:45 +1100 Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> wrote:
> >
> > After merging the kvm tree, today's linux-next build (htmldocs) produced
> > this warning:
> >
> > Documentation/virt/kvm/locking.rst:157: ERROR: Malformed table.
> >
> > +-------------------------------------------------------------------------+
> > | At the beginning:: |
> > | |
> > | spte.W = 0 |
> > | spte.Accessed = 1 |
> > +-------------------------------------+-----------------------------------+
> > | CPU 0: | CPU 1: |
> > +-------------------------------------+-----------------------------------+
> > | In mmu_spte_update():: | |
> > | | |
> > | old_spte = *spte; | |
> > | | |
> > | | |
> > | /* 'if' condition is satisfied. */ | |
> > | if (old_spte.Accessed == 1 && | |
> > | old_spte.W == 0) | |
> > | spte = new_spte; | |
> > +-------------------------------------+-----------------------------------+
> > | | on fast page fault path:: |
> > | | |
> > | | spte.W = 1 |
> > | | |
> > | | memory write on the spte:: |
> > | | |
> > | | spte.Dirty = 1 |
> > +-------------------------------------+-----------------------------------+
> > | :: | |
> > | | |
> > | else | |
> > | old_spte = xchg(spte, new_spte);| |
> > | if (old_spte.Accessed && | |
> > | !new_spte.Accessed) | |
> > | flush = true; | |
> > | if (old_spte.Dirty && | |
> > | !new_spte.Dirty) | |
> > | flush = true; | |
> > | OOPS!!! | |
> > +-------------------------------------+-----------------------------------+
> >
> > Introduced by commit
> >
> > 5f6a3badbb74 ("KVM: x86/mmu: Mark page/folio accessed only when zapping leaf SPTEs")
>
> I am still seeing this warning.

Paolo, can you grab the patch from Bagas?

https://lore.kernel.org/all/20241028125835.26714-1-bagasdotme@xxxxxxxxx