+ mm-use-mmap_assert_write_locked-instead-of-open-coding-it.patch added to -mm tree

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm/mmap.c: use mmap_assert_write_locked() instead of open coding it
has been added to the -mm tree.  Its filename is
     mm-use-mmap_assert_write_locked-instead-of-open-coding-it.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-use-mmap_assert_write_locked-instead-of-open-coding-it.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-use-mmap_assert_write_locked-instead-of-open-coding-it.patch

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------------------------------------------------------
From: Rolf Eike Beer <eb@emlix.com>
Subject: mm/mmap.c: use mmap_assert_write_locked() instead of open coding it

In case the lock is actually not held at this point this also avoids a
stale lock reference if built with NDEBUG.

Link: https://lkml.kernel.org/r/5827758.TJ1SttVevJ@mobilepool36.emlix.com
Signed-off-by: Rolf Eike Beer <eb@emlix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/mmap.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/mm/mmap.c~mm-use-mmap_assert_write_locked-instead-of-open-coding-it
+++ a/mm/mmap.c
@@ -3561,7 +3561,7 @@ int mm_take_all_locks(struct mm_struct *
 	struct vm_area_struct *vma;
 	struct anon_vma_chain *avc;
 
-	BUG_ON(mmap_read_trylock(mm));
+	mmap_assert_write_locked(mm);
 
 	mutex_lock(&mm_all_locks_mutex);
 
@@ -3641,7 +3641,7 @@ void mm_drop_all_locks(struct mm_struct
 	struct vm_area_struct *vma;
 	struct anon_vma_chain *avc;
 
-	BUG_ON(mmap_read_trylock(mm));
+	mmap_assert_write_locked(mm);
 	BUG_ON(!mutex_is_locked(&mm_all_locks_mutex));
 
 	for (vma = mm->mmap; vma; vma = vma->vm_next) {
_

Patches currently in -mm which might be from eb@emlix.com are

mm-use-mmap_assert_write_locked-instead-of-open-coding-it.patch