On Tue, 23 Oct 2007, Rafael J. Wysocki wrote: > > The problem here is that the buffer mutexes are not distinguishable. > > I don't quite get the "which lock already depends on the new lock" part. > > Well, I have always had problems with understanding what lockdep actually > traces ... The basic idea is simple enough. Lockdep looks for events which seem to be problematic, such as lock A being acquired while lock B is held if earlier on somebody acquired B while holding A. The difficulty lies in the "_seem_ to be" part -- lockdep can't keep track of each and every individual lock in the system. Instead it groups them into categories based on the structures they lie in. So if A and A' are both pm_mutex members but belonging to two different structures, lockdep won't be able to tell them apart without help. If someone acquires A then B, and someone else acquires B then A', lockdep will report a violation. Alan Stern _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
