The patch titled Subject: mm: disable CONFIG_PER_VMA_LOCK until its fixed has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-disable-config_per_vma_lock-until-its-fixed.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days

------------------------------------------------------ From: Suren Baghdasaryan surenb@google.com Subject: mm: disable CONFIG_PER_VMA_LOCK until its fixed Date: Tue, 4 Jul 2023 23:37:11 -0700

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@google.com

Link: https://lkml.kernel.org/r/20230705063711.2670599-3-surenb@google.com Signed-off-by: Suren Baghdasaryan surenb@google.com Reported-by: Jiri Slaby jirislaby@kernel.org Closes: https://lore.kernel.org/all/dbdef34c-3a07-5951-e1ae-e9c6e3cdf51b@kernel.org/ Reported-by: Jacob Young jacobly.alt@gmail.com Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217624 Fixes: 0bff0aaea03e ("x86/mm: try VMA lock-based page fault handling first") Cc: Andy Lutomirski luto@kernel.org Cc: Axel Rasmussen axelrasmussen@google.com Cc: Bagas Sanjaya bagasdotme@gmail.com Cc: Chris Li chriscli@google.com Cc: David Hildenbrand david@redhat.com Cc: David Howells dhowells@redhat.com Cc: Davidlohr Bueso dave@stgolabs.net Cc: David Rientjes rientjes@google.com Cc: Eric Dumazet edumazet@google.com Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: Greg Thelen gthelen@google.com Cc: Hans de Goede hdegoede@redhat.com Cc: Holger Hoffst��tte holger@applied-asynchrony.com Cc: Hugh Dickins hughd@google.com Cc: Ingo Molnar mingo@redhat.com Cc: Jann Horn jannh@google.com Cc: Joel Fernandes joelaf@google.com Cc: Johannes Weiner hannes@cmpxchg.org Cc: Kent Overstreet kent.overstreet@linux.dev Cc: Laurent Dufour ldufour@linux.ibm.com Cc: Liam R. Howlett Liam.Howlett@oracle.com Cc: Lorenzo Stoakes lstoakes@gmail.com Cc: Matthew Wilcox willy@infradead.org Cc: Mel Gorman mgorman@techsingularity.net Cc: Michal Hocko mhocko@suse.com Cc: Michel Lespinasse michel@lespinasse.org Cc: Mike Rapoport (IBM) rppt@kernel.org Cc: Minchan Kim minchan@google.com Cc: "Paul E. McKenney" paulmck@kernel.org Cc: Peter Xu peterx@redhat.com Cc: peterz@infradead.org Cc: Punit Agrawal punit.agrawal@bytedance.com Cc: regressions@lists.linux.dev Cc: Sebastian Andrzej Siewior bigeasy@linutronix.de Cc: Shakeel Butt shakeelb@google.com Cc: Song Liu songliubraving@fb.com Cc: Vlastimil Babka vbabka@suse.cz Cc: Will Deacon will@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

mm/Kconfig | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/mm/Kconfig~mm-disable-config_per_vma_lock-until-its-fixed +++ a/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.

_

Patches currently in -mm which might be from surenb@google.com are

fork-lock-vmas-of-the-parent-process-when-forking.patch mm-disable-config_per_vma_lock-until-its-fixed.patch swap-remove-remnants-of-polling-from-read_swap_cache_async.patch mm-add-missing-vm_fault_result_trace-name-for-vm_fault_completed.patch mm-drop-per-vma-lock-when-returning-vm_fault_retry-or-vm_fault_completed.patch mm-change-folio_lock_or_retry-to-use-vm_fault-directly.patch mm-handle-swap-page-faults-under-per-vma-lock.patch mm-handle-userfaults-under-vma-lock.patch mm-disable-config_per_vma_lock-by-default-until-its-fixed.patch