Documentation/locking/lockdep-design.rst

129 deadlock may happen. For example, in the scenario that after this lock
131 lock will be attempted to acquire twice, which creates a deadlock,
132 referred to as lock recursion deadlock.
148 because this could lead to a deadlock - referred to as lock inversion
149 deadlock - as attempts to acquire the two locks form a circle which
164 thus could result in a lock inversion deadlock. Likewise, a softirq-safe
189 could lead to a lock inversion deadlock - even if that lock scenario did
289 lock related deadlock. [1]_
292 occur in practice to prove a deadlock: only the simple 'component'
402 to deadlock possibility.
421 While non-recursive readers will cause a self deadlock if trying to acquire inside
439 and there is no deadlock. However, if read_lock_2() is non-recursive readers,
440 it will get blocked by writer waiter B, and cause a self deadlock.
480 is not a deadlock for recursive read locks, as while the task B is waiting for
483 case is a deadlock, because even if the write_lock() in TASK B cannot get the
500 A deadlock case with recursive locks involved is as follow::
517 deadlock detection.
524 And in deadlock detection, we care whether we could get blocked on L2 with L1 held,
581 Recursive Read Deadlock Detection:
589 combination of locking sequences that causes deadlock. I.e. a strong circle is
590 sufficient for deadlock detection.
595 combination of locking sequences that could cause deadlock. I.e.  strong
596 circles are necessary for deadlock detection.
600 deadlock possibility. As a closed strong path stands for a dependency chain that
618 We now can construct a combination of locking sequences that cause deadlock:
634 waiting scenario and nobody can get progress, therefore a deadlock.
638 Lemma 2 is equivalent to: If there is a deadlock scenario, then there must be a
641 According to Wikipedia[1], if there is a deadlock, then there must be a circular
662 [1]: https://en.wikipedia.org/wiki/Deadlock