At Sat, 25 Aug 2012 07:16:21 -0500, Bruno Wolff III wrote:

On Sat, Aug 25, 2012 at 08:13:27 -0400, Josh Boyer jwboyer@redhat.com wrote:

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On Sat, Aug 25, 2012 at 07:07:40AM -0500, Bruno Wolff III wrote:

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On Sat, Aug 25, 2012 at 14:02:51 +0200, Daniel Mack zonque@gmail.com wrote:

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Can you revert commit e9ba389c5 ("ALSA: usb-audio: Fix scheduling-while-atomic bug in PCM capture stream") and see if that

I can try that, but it takes a long time to build a new kernel on my old hardware.

I started a scratch build of a kernel with that patch reverted (via patch -R). You'll find it here when it finishes:

http://koji.fedoraproject.org/koji/taskinfo?taskID=4421817

josh

I'll test it when it finishes. Thanks. It takes me a long time to build kernels locally, and I wasn't sure how to do a scratch build on koji without committing stuff remotely.

Actually you don't have to rebuild the whole kernel at all just for debugging this usb-audio bug. The workflow below is what I do often for debugging a driver problem on a distro kernel.

1. Prepare the compile-ready kernel source tree corresponding to your running kernel. This may depend on distro; in the case of SUSE, kernel-default-devel.rpm must be installed for kernel-default.rpm, for example.

2. Copy sound/usb subdirectory of the kernel source tree locally anywhere else, say, $HOME/usb. It can be a normal user directory.

3. Apply the patch to that local directory.

4. Build modules as a normal user like % make -C /lib/modules/$(uname -r)/build M=$HOME/usb modules

5. Make an extra update directory in the module directory once, e.g. # mkdir /lib/modules/$(uname -r)/updates

6. Copy *.ko files to there # cp $HOME/usb/*.ko /lib/modules/$(uname -r)/updates

7. Run depmod once # /sbin/depmod -a

8. Reload snd-usb-audio module.

If you want to take back to the original module, just remove updates module directory and run depmod again. Pretty convenient, eh?

HTH,

Takashi