At Thu, 18 Feb 2010 07:25:38 -0500, Ed Tomlinson wrote:
On Wednesday 17 February 2010 09:29:37 Takashi Iwai wrote:
At Wed, 17 Feb 2010 08:16:32 -0500, Ed Tomlinson wrote:
On Tuesday 16 February 2010 08:37:46 Takashi Iwai wrote:
Thanks for the patch. It helps in that it eliminates the opps but lockdep still triggers and aplay still fails. Here is the new traceback.
Hmm, fixing this isn't so trivial. The same problem occurs on other subsystems like NFS over years. And it's still there, AFAIK. The mmap mutex appears suddenly in the strange code path at close.
The patch below might fix, but I'm not 100% sure whether this has no side effect.
Anyway, I doubt very much it being a regression. There is no change in ALSA core side, and also in V4L em28xx code. Maybe the lockdep wasn't triggered by some reason. And, this lockdep warning is almost harmless...
Takashi,
The second patch eliminating the lock causes oppes every time (one follows just in case its helpful).
Are you sure? The patch should causes a compile error, so you must have patched manually in a wrong place ;)
Yes I am sure. I fixed the compile error the same way it is fixed below.
But the Oops looks pretty irrelevant from the code path.
Takashi