[alsa-devel] Problems with snd_hda_intel in Linux kernel 2.6.38

[Takashi Iwai]

At Tue, 29 Mar 2011 12:58:16 +0200,
Svante Signell wrote:
> 
> On Tue, 2011-03-29 at 12:31 +0200, Takashi Iwai wrote:
> > At Tue, 29 Mar 2011 12:24:40 +0200,
> > Svante Signell wrote:
> > > 
> > > > This problem was also reported as Debian bug #613979, as kernel ticket
> > > > 
> > > > https://bugzilla.kernel.org/show_bug.cgi?id=30552
> > 
> > Did you look at this?
> 
> Yes I did. So you recommend me to compile a new kernel? 

Yes, at least, we can know whether it's a regression in HD-audio side
or in another part.  But let's check the Oops first as below.

> > Also, please try to decode the line from the code shown in the Oops.
> > It's a bit too little information to analyze, unfortunately.
> 
> I know there is little information, but the computer hangs during boot
> as shown in the bug report and the information there is copied manually
> during the timeout period. Then everything is blanked out since the boot
> continues. Any ideas?

As mentioned, you can decode the binary dump in Oops to guess which
line of the source code corresponds to the Oops point.
Use gdb or objdump to figure out the disassembled code.
For example,

	% objdump -D -l /lib/modules/$(uname -r)/kernel/sound/pci/hda/snd-hda-intel.ko

Then look for azx_probe.  Calculate the position from the offset
Oops gave, compare the hex codes with the data show in "Code" section
of Oops.
objdump with -l will show the source code line as well, so you'll see
now more exactly where it was triggered.


Takashi