Re: [PATCH 0/2] console_lock debug improvements

On Wed, 22 Aug 2012 00:34:30 +0200 Daniel Vetter daniel.vetter@ffwll.ch wrote:

Hi all,

After Dave Airlie blew through a few days to track down a deadlock at boot-up when handing over from the firmware fb to the kms/drm framebuffer driver (1), I've figured that lockdep /should/ have caught this.

And indeed, by adding proper annotations to the console_lock it complains about the potential deadlock when exercising the entire driver life-cycle of just one fb driver (i.e. not even a handover required). While at it, I've replaced the existing in_interrupt check with the more paranoid might_sleep.

Comments, flames and review highly welcome.

This will be an absolute godsend for DRI debugging. Definitely wants to go in.

Alan