+ mm-prevent-do_swap_page-from-handling-page-faults-under-vma-lock.patch added to mm-unstable branch

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



The patch titled
     Subject: mm: prevent do_swap_page from handling page faults under VMA lock
has been added to the -mm mm-unstable branch.  Its filename is
     mm-prevent-do_swap_page-from-handling-page-faults-under-vma-lock.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-prevent-do_swap_page-from-handling-page-faults-under-vma-lock.patch

This patch will later appear in the mm-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@xxxxxxxxxx>
Subject: mm: prevent do_swap_page from handling page faults under VMA lock
Date: Mon, 27 Feb 2023 09:36:25 -0800

Due to the possibility of do_swap_page dropping mmap_lock, abort fault
handling under VMA lock and retry holding mmap_lock.  This can be handled
more gracefully in the future.

Link: https://lkml.kernel.org/r/20230227173632.3292573-27-surenb@xxxxxxxxxx
Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Reviewed-by: Laurent Dufour <laurent.dufour@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---


--- a/mm/memory.c~mm-prevent-do_swap_page-from-handling-page-faults-under-vma-lock
+++ a/mm/memory.c
@@ -3689,6 +3689,11 @@ vm_fault_t do_swap_page(struct vm_fault
 	if (!pte_unmap_same(vmf))
 		goto out;
 
+	if (vmf->flags & FAULT_FLAG_VMA_LOCK) {
+		ret = VM_FAULT_RETRY;
+		goto out;
+	}
+
 	entry = pte_to_swp_entry(vmf->orig_pte);
 	if (unlikely(non_swap_entry(entry))) {
 		if (is_migration_entry(entry)) {
_

Patches currently in -mm which might be from surenb@xxxxxxxxxx are

mm-introduce-config_per_vma_lock.patch
mm-move-mmap_lock-assert-function-definitions.patch
mm-add-per-vma-lock-and-helper-functions-to-control-it.patch
mm-mark-vma-as-being-written-when-changing-vm_flags.patch
mm-mmap-move-vma_prepare-before-vma_adjust_trans_huge.patch
mm-khugepaged-write-lock-vma-while-collapsing-a-huge-page.patch
mm-mmap-write-lock-vmas-in-vma_prepare-before-modifying-them.patch
mm-mremap-write-lock-vma-while-remapping-it-to-a-new-address-range.patch
mm-write-lock-vmas-before-removing-them-from-vma-tree.patch
mm-conditionally-write-lock-vma-in-free_pgtables.patch
kernel-fork-assert-no-vma-readers-during-its-destruction.patch
mm-mmap-prevent-pagefault-handler-from-racing-with-mmu_notifier-registration.patch
mm-introduce-vma-detached-flag.patch
mm-introduce-lock_vma_under_rcu-to-be-used-from-arch-specific-code.patch
mm-fall-back-to-mmap_lock-if-vma-anon_vma-is-not-yet-set.patch
mm-add-fault_flag_vma_lock-flag.patch
mm-prevent-do_swap_page-from-handling-page-faults-under-vma-lock.patch
mm-prevent-userfaults-to-be-handled-under-per-vma-lock.patch
mm-introduce-per-vma-lock-statistics.patch
x86-mm-try-vma-lock-based-page-fault-handling-first.patch
arm64-mm-try-vma-lock-based-page-fault-handling-first.patch
mm-mmap-free-vm_area_struct-without-call_rcu-in-exit_mmap.patch
mm-separate-vma-lock-from-vm_area_struct.patch
per-vma-locks.patch




[Index of Archives]     [Kernel Archive]     [IETF Annouce]     [DCCP]     [Netdev]     [Networking]     [Security]     [Bugtraq]     [Yosemite]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux SCSI]

  Powered by Linux