From: Rolf Eike Beer 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. Link: https://lkml.kernel.org/r/5827758.TJ1SttVevJ@mobilepool36.emlix.com Signed-off-by: Rolf Eike Beer Reviewed-by: Christoph Hellwig Signed-off-by: Andrew Morton --- 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 @@ -3553,7 +3553,7 @@ 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); @@ -3633,7 +3633,7 @@ 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) { _