mm: lock newly mapped VMA with corrected ordering
authorHugh Dickins <hughd@google.com>
Sat, 8 Jul 2023 23:04:00 +0000 (16:04 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Sat, 8 Jul 2023 23:44:11 +0000 (16:44 -0700)
commit1c7873e3364570ec89343ff4877e0f27a7b21a61
tree1368b56679e63ef9a016aca41408e66ba7d6365f
parent946c6b59c56dc6e7d8364a8959cb36bf6d10bc37
mm: lock newly mapped VMA with corrected ordering

Lockdep is certainly right to complain about

  (&vma->vm_lock->lock){++++}-{3:3}, at: vma_start_write+0x2d/0x3f
                 but task is already holding lock:
  (&mapping->i_mmap_rwsem){+.+.}-{3:3}, at: mmap_region+0x4dc/0x6db

Invert those to the usual ordering.

Fixes: 33313a747e81 ("mm: lock newly mapped VMA which can be modified after it becomes visible")
Cc: stable@vger.kernel.org
Signed-off-by: Hugh Dickins <hughd@google.com>
Tested-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/mmap.c