[PATCH 0/1] iwlwifi: trace debug messages

Seth Forshee seth.forshee at canonical.com
Tue Sep 4 15:00:05 UTC 2012


On Tue, Sep 04, 2012 at 12:04:59PM +0100, Andy Whitcroft wrote:
> On Mon, Sep 03, 2012 at 01:52:44PM +0100, Luis Henriques wrote:
> 
> > It looks like the issue is due to an overflow of debug messages to the
> > kernel logs.  After bisecting the kernel, commit:
> > 
> > 2655e314c4b204966008689eaf3e87ba1f38d55c iwlwifi: trace debug messages
> > 
> > does fix the problem.  This commit had to be backported to the Precise
> > kernel as it didn't applied cleanly.  The original bug reporter claims
> > the issue is fixed with this backport.
> 
> This is rather a large patch which must fix the issue as a side effect
> rather than really fixing the original issue.  I am not against fixing
> this this way I guess, but it does feel a little heavy handed.  Did we
> have any idea which debug message was triggering the crash?

The upside of bringing in all of these changes (besides fixing the
issue) is that we can get the messages in the trace buffer. I got a demo
from Johannes Berg last week of how he uses the tracing in mac80211 and
iwlwifi for debugging wirless problems, and it looks *very* useful.
While the changes may be a bit of overkill for fixing the particular
bug, I think they'll prove useful.

Seth




More information about the kernel-team mailing list