On Sun, Feb 12, 2023 at 10:23:44AM -0500, Alan Stern wrote: > Provided it acquires the parent device's lock first, this is > utterly safe no matter what order the children are locked in. Try > telling that to lockdep! mutex_lock_next_lock(child->lock, parent->lock) is there to express this exact pattern, it allows taking multiple child->lock class locks (in any order) provided parent->lock is held.
