Commit 2507003a authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Peter Zijlstra
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lockdep: Let lock_is_held_type() detect recursive read as read 



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: e9181886 ("locking: More accurate annotations for read_lock()")
Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: default avatarBoqun Feng <boqun.feng@gmail.com>
Acked-by: default avatarWaiman Long <longman@redhat.com>
Link: https://lkml.kernel.org/r/20210903084001.lblecrvz4esl4mrr@linutronix.de
parent 12235da8

kernel/locking/lockdep.c

+1 −1
Original line number Diff line number Diff line
@@ -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;