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From:   Suren Baghdasaryan <surenb@google.com>
Date:   Wed, 5 Jul 2023 17:32:09 -0700
Message-ID: <CAJuCfpGWW7wsrtqi4rZUz4vxW-N0CaUEeUqY4e7iX1hzgRsT2g@mail.gmail.com>
Subject: Re: [PATCH v3 2/2] mm: disable CONFIG_PER_VMA_LOCK until its fixed
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     Peter Xu <peterx@redhat.com>, David Hildenbrand <david@redhat.com>,
        jirislaby@kernel.org, jacobly.alt@gmail.com,
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On Wed, Jul 5, 2023 at 5:30=E2=80=AFPM Suren Baghdasaryan <surenb@google.co=
m> wrote:
>
> On Wed, Jul 5, 2023 at 5:24=E2=80=AFPM Andrew Morton <akpm@linux-foundati=
on.org> wrote:
> >
> > On Wed, 5 Jul 2023 13:33:26 -0700 Suren Baghdasaryan <surenb@google.com=
> wrote:
> >
> > > I was hoping we could re-enable VMA locks in 6.4 once we get more
> > > confirmations that the problem is gone. Is that not possible once the
> > > BROKEN dependency is merged?
> >
> > I think "no".  By doing this we're effectively backporting a minor
> > performance optimization, which isn't a thing we'd normally do.
>
> In that case, maybe for 6.4 we send the fix and only disable it by
> default without marking BROKEN? That way we still have a way to enable
> it if desired?

I'm preparing the next version with Liam's corrections. If the above
option I suggested is acceptable I can send a modified second patch
which would not have BROKEN dependency.

>
> >