This is a note to let you know that I've just added the patch titled lockdep: Let lock_is_held_type() detect recursive read as read to the 5.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: lockdep-let-lock_is_held_type-detect-recursive-read-.patch and it can be found in the queue-5.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 0c56655920aaa8d592b34d0f5aa3b7c76bf55431 Author: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Date: Fri Sep 3 10:40:01 2021 +0200 lockdep: Let lock_is_held_type() detect recursive read as read [ Upstream commit 2507003a1d10917c9158077bf6030719d02c941e ] lock_is_held_type(, 1) detects acquired read locks. It only recognized locks acquired with lock_acquire_shared(). Read locks acquired with lock_acquire_shared_recursive() are not recognized because a `2' is stored as the read value. Rework the check to additionally recognise lock's read value one and two as a read held lock. Fixes: e918188611f07 ("locking: More accurate annotations for read_lock()") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Acked-by: Boqun Feng <boqun.feng@xxxxxxxxx> Acked-by: Waiman Long <longman@xxxxxxxxxx> Link: https://lkml.kernel.org/r/20210903084001.lblecrvz4esl4mrr@xxxxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 8a509672a4cc9..d624231eab2bb 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -5366,7 +5366,7 @@ int __lock_is_held(const struct lockdep_map *lock, int read) struct held_lock *hlock = curr->held_locks + i; if (match_held_lock(hlock, lock)) { - if (read == -1 || hlock->read == read) + if (read == -1 || !!hlock->read == read) return LOCK_STATE_HELD; return LOCK_STATE_NOT_HELD;