The patch titled
Subject: mm/mmap: write-lock VMAs in vma_prepare before modifying them
has been added to the -mm mm-unstable branch. Its filename is
mm-mmap-write-lock-vmas-in-vma_prepare-before-modifying-them.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-mmap-write-lock-vmas-in-vma_prepare-before-modifying-them.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Subject: mm/mmap: write-lock VMAs in vma_prepare before modifying them
Date: Mon, 27 Feb 2023 09:36:15 -0800
Write-lock all VMAs which might be affected by a merge, split, expand or
shrink operations. All these operations use vma_prepare() before making
the modifications, therefore it provides a centralized place to perform
VMA locking.
Link: https://lkml.kernel.org/r/20230227173632.3292573-17-surenb@xxxxxxxxxx
Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/mm/mmap.c~mm-mmap-write-lock-vmas-in-vma_prepare-before-modifying-them
+++ a/mm/mmap.c
@@ -502,6 +502,16 @@ static inline void init_vma_prep(struct
*/
static inline void vma_prepare(struct vma_prepare *vp)
{
+ if (vp->vma)
+ vma_start_write(vp->vma);
+ if (vp->adj_next)
+ vma_start_write(vp->adj_next);
+ /* vp->insert is always a newly created VMA, no need for locking */
+ if (vp->remove)
+ vma_start_write(vp->remove);
+ if (vp->remove2)
+ vma_start_write(vp->remove2);
+
if (vp->file) {
uprobe_munmap(vp->vma, vp->vma->vm_start, vp->vma->vm_end);
_
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
