On 21.10.2012 22:43, Artem S. Tashkinov wrote:

...

Nice. Could you do that again with the patch applied I sent yo some hours ago?

That patch was of no help - the system has crashed and I couldn't spot relevant messages.

I've no idea what it means.

The sequence of driver callbacks issued on a stream start is

.open() .hw_params() .prepare() .trigger()

If the ALSA part really causes this issue, the bad things happen either in any of the driver callback functions or in the core underneath.

The patch I sent returns an error from the hw_params callback, and as you still see the problem, that means that the crash happens before any of the USB audio streaming really starts.

Could you try and return -EINVAL from snd_usb_capture_open() please?

If anyone has a better idea on how to debug this, please chime in.

Daniel