Hi Tomi, On 11/11/2013 09:59 PM, Tomi Valkeinen wrote: > On 2013-11-05 12:00, Gu Zheng wrote: >> Following commits: >> 50e244cc79 fb: rework locking to fix lock ordering on takeover >> e93a9a8687 fb: Yet another band-aid for fixing lockdep mess >> 054430e773 fbcon: fix locking harder >> reworked locking to fix related lock ordering on takeover, and introduced console_lock >> into fbmem, but it seems that the new lock sequence(fb_info->lock ---> console_lock) >> is against with the one in console_callback(console_lock ---> fb_info->lock), and leads to >> a potential dead lock as following: > > <snip> > >> so we reorder the lock sequence the same as it in console_callback() to >> avoid this issue. And following Tomi's suggestion, fix these similar >> issues all in fb subsystem. >> >> Signed-off-by: Gu Zheng <guz.fnst@xxxxxxxxxxxxxx> >> --- >> drivers/video/fbmem.c | 50 ++++++++++++++++++++++++------------- >> drivers/video/fbsysfs.c | 19 ++++++++++---- >> drivers/video/sh_mobile_lcdcfb.c | 10 ++++--- >> 3 files changed, 51 insertions(+), 28 deletions(-) > > I'll apply this for 3.13. It's a bit difficult to verify if the locking > is now correct, but looks fine to me. And we can revert this easily if > things break badly. Thanks very munch.:) Regards, Gu > > Tomi > > -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
