diff options
| author | zhong jiang <zhongjiang@huawei.com> | 2019-11-18 11:26:10 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-11-25 09:53:09 +0100 |
| commit | e0088cfbd8c94554f96b9b20897d9c3496305a09 (patch) | |
| tree | 135abfabd47d4d94c0115315c593aeed4926d768 /mm | |
| parent | 6988feec3da07e2c67a4ef8ab015fab23ea33c6e (diff) | |
memfd: Use radix_tree_deref_slot_protected to avoid the warning.
The commit 3ce6b467b9b2 ("memfd: Fix locking when tagging pins")
introduces the following warning messages.
*WARNING: suspicious RCU usage in memfd_wait_for_pins*
It is because we still use radix_tree_deref_slot without read_rcu_lock.
We should use radix_tree_deref_slot_protected instead in the case.
Cc: stable@vger.kernel.org
Fixes: 3ce6b467b9b2 ("memfd: Fix locking when tagging pins")
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/shmem.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/shmem.c b/mm/shmem.c index ac8a5fedc245..6266a7d1ba00 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2464,7 +2464,7 @@ static void shmem_tag_pins(struct address_space *mapping) spin_lock_irq(&mapping->tree_lock); radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) { - page = radix_tree_deref_slot(slot); + page = radix_tree_deref_slot_protected(slot, &mapping->tree_lock); if (!page || radix_tree_exception(page)) { if (radix_tree_deref_retry(page)) { slot = radix_tree_iter_retry(&iter); |