At Wed, 23 Jan 2013 17:25:08 +0100, Daniel Vetter wrote: > > From: Alan Cox <alan at lxorguk.ukuu.org.uk> > > Adjust the console layer to allow a take over call where the caller already > holds the locks. Make the fb layer lock in order. > > This s partly a band aid, the fb layer is terminally confused about the > locking rules it uses for its notifiers it seems. > > Signed-off-by: Alan Cox <alan at linux.intel.com> > [danvet: Tiny whitespace cleanup.] > Reported-and-tested-by: Hugh Dickins <hughd at google.com> > Reported-and-tested-by: Sasha Levin <levinsasha928 at gmail.com> > References: https://lkml.org/lkml/2012/10/25/516 > Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch> FYI, the latest patch of this is found in mm tree: http://ozlabs.org/~akpm/mmots/broken-out/fb-rework-locking-to-fix-lock-ordering-on-takeover.patch Also I hit the same problem in another code paths (for unbind and unregister): http://marc.info/?t=135309396400003&r=1&w=2 My additional patch is found in mm tree, too: http://ozlabs.org/~akpm/mmots/broken-out/fb-yet-another-band-aid-for-fixing-lockdep-mess.patch Takashi
