On Tue 29-04-14 11:38:04, Andy Shevchenko wrote: > On Mon, 2014-04-28 at 21:24 +0200, Jan Kara wrote: > > On Mon 28-04-14 14:14:39, Steven Rostedt wrote: > > > On Mon, 28 Apr 2014 19:51:39 +0200 > > > Jan Kara wrote: > > > > > > > On Mon 28-04-14 13:43:31, Steven Rostedt wrote: > > > > > Things have changed with regard to printk() in linux-next. Now it > > > > > appears that lockdep is going haywire over it. I don't understand the > > > > > exact reason for the lockdep_off() and lockdep_on() logic that is in > > > > > printk(), but it obviously seems to be causing issues with the new > > > > > changes. > > > > > > > > > > Care to take a look? > > > > The obvious cause is that I moved lockdep_on() somewhat earlier in > > > > vprintk_emit() so lockdep now covers more of printk code. And apparently > > > > something is wrong there... > > > > > > > > > > Exactly, and I rather know *exactly* what is wrong before we just start > > > throwing patches at the problem and hope it goes away. That's not how > > > to solve a software bug. > > So I had a look and we are missing mutex_release() in > > console_trylock_for_printk() if we don't have a console to print to. > > Attached patch should fix the problem. > > Besides it doesn't apply clearly on top of today's linux-next, it > doesn't fix the issue, but modifies it a bit. Sorry, I was too tired and missed conversion of one place. Attached is a new version of the patch which also applies cleanly against linux-next. Honza -- Jan Kara SUSE Labs, CR