Re: [PATCH v3 2/2] mm: disable CONFIG_PER_VMA_LOCK until its fixed

[Suren Baghdasaryan]

On Wed, Jul 5, 2023 at 10:24 AM David Hildenbrand <david@xxxxxxxxxx> wrote:
>
> On 05.07.23 19:22, Suren Baghdasaryan wrote:
> > On Wed, Jul 5, 2023 at 10:16 AM David Hildenbrand <david@xxxxxxxxxx> wrote:
> >>
> >> On 05.07.23 19:12, Suren Baghdasaryan wrote:
> >>> A memory corruption was reported in [1] with bisection pointing to the
> >>> patch [2] enabling per-VMA locks for x86.
> >>> Disable per-VMA locks config to prevent this issue while the problem is
> >>> being investigated. This is expected to be a temporary measure.
> >>>
> >>> [1] https://bugzilla.kernel.org/show_bug.cgi?id=217624
> >>> [2] https://lore.kernel.org/all/20230227173632.3292573-30-surenb@xxxxxxxxxx
> >>>
> >>> Reported-by: Jiri Slaby <jirislaby@xxxxxxxxxx>
> >>> Closes: https://lore.kernel.org/all/dbdef34c-3a07-5951-e1ae-e9c6e3cdf51b@xxxxxxxxxx/
> >>> Reported-by: Jacob Young <jacobly.alt@xxxxxxxxx>
> >>> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217624
> >>> Fixes: 0bff0aaea03e ("x86/mm: try VMA lock-based page fault handling first")
> >>> Cc: stable@xxxxxxxxxxxxxxx
> >>> Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> >>> ---
> >>>    mm/Kconfig | 3 ++-
> >>>    1 file changed, 2 insertions(+), 1 deletion(-)
> >>>
> >>> diff --git a/mm/Kconfig b/mm/Kconfig
> >>> index 09130434e30d..0abc6c71dd89 100644
> >>> --- a/mm/Kconfig
> >>> +++ b/mm/Kconfig
> >>> @@ -1224,8 +1224,9 @@ config ARCH_SUPPORTS_PER_VMA_LOCK
> >>>           def_bool n
> >>>
> >>>    config PER_VMA_LOCK
> >>> -     def_bool y
> >>> +     bool "Enable per-vma locking during page fault handling."
> >>>        depends on ARCH_SUPPORTS_PER_VMA_LOCK && MMU && SMP
> >>> +     depends on BROKEN
> >>>        help
> >>>          Allow per-vma locking during page fault handling.
> >>>
> >> Do we have any testing results (that don't reveal other issues :) ) for
> >> patch #1? Not sure if we really want to mark it broken if patch #1 fixes
> >> the issue.
> >
> > I tested the fix using the only reproducer provided in the reports
> > plus kernel compilation and my fork stress test. All looked good and
> > stable but I don't know if other reports had the same issue or
> > something different.
>
> Can you point me at the other reports, so I can quickly scan them?

by Jacob Young: https://bugzilla.kernel.org/show_bug.cgi?id=217624
by Jiri Slaby: https://lore.kernel.org/all/dbdef34c-3a07-5951-e1ae-e9c6e3cdf51b@xxxxxxxxxx/
by Holger Hoffstätte:
https://lore.kernel.org/all/b198d649-f4bf-b971-31d0-e8433ec2a34c@xxxxxxxxxxxxxxxxxxxxxx/
only saying that Firefox started crashing after upgrading to 6.4.1

>
> --
> Cheers,
>
> David / dhildenb
>