On Sat, Apr 11, 2009 at 11:21:31AM -0700, Andrew Morton wrote: > On Sat, 11 Apr 2009 17:04:00 +0200 Andrea Righi <righi.andrea@xxxxxxxxx> wrote: > > > fbdev: fix info->lock deadlock in fbcon_event_notify() > > > > fb_notifier_call_chain() is called with info->lock held, i.e. in > > do_fb_ioctl() => FBIOPUT_VSCREENINFO => fb_set_var() and the some > > notifier callbacks, like fbcon_event_notify(), try to re-acquire > > info->lock again. > > > > Remove the lock/unlock_fb_info() in all the framebuffer notifier > > callbacks' and be sure to always call fb_notifier_call_chain() with > > info->lock held. > > Thanks. So do you think we should proceed with this patch instead of > reverting 66c1ca0? Yes, there's no need to revert 66c1ca0 now, otherwise we'll simply reintroduce the info->lock / mm->mmap_sem circular locking dependency. I'd like to test the fbdev mode switching, but it seems intelfb doesn't support it with LVDS ports (and at the moment I've not a CRT here...). Anyway, if someone will have troubles with mode switching I'm quite sure we can fix it on top of this patch. -Andrea _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
