On Wed, 2017-09-20 at 21:27 +0200, Christian Lamparter wrote: > It seems this is caused as a result of: > -> lock_map_acquire(&work->lockdep_map); > lock_map_release(&work->lockdep_map); > > in flush_work() [0]
Agree. > This was added by: > > commit 0976dfc1d0cd80a4e9dfaf87bd8744612bde475a > Author: Stephen Boyd <sb...@codeaurora.org> > Date: Fri Apr 20 17:28:50 2012 -0700 > > workqueue: Catch more locking problems with flush_work() Yes, but that doesn't matter. > Looking at the Stephen's patch, it's clear that it was made > with "static DECLARE_WORK(work, my_work)" in mind. However > p54's led_work is "per-device", hence it is stored in the > devices context p54_common, which is dynamically allocated. > So, maybe revert Stephen's patch? I disagree - as the lockdep warning says: > > INFO: trying to register non-static key. > > the code is fine but needs lockdep annotation. > > turning off the locking correctness validator. What it needs is to actually correctly go through initializing the work at least once. Without more information, I can't really say what's going on, but I assume that something is failing and p54_unregister_leds() is getting invoked without p54_init_leds() having been invoked, so essentially it's trying to flush a work that was never initialized? INIT_DELAYED_WORK() does, after all, initialize the lockdep map properly via __INIT_WORK(). johannes
