On 21.10.2012 16:57, Artem S. Tashkinov wrote:

...

On Oct 21, 2012, Daniel Mack wrote:

[Cc: alsa-devel]

On 21.10.2012 14:30, Artem S. Tashkinov wrote:

...

On Oct 21, 2012, Daniel Mack wrote:

...

A hint at least. How did you enable the audio record exactly? Can you reproduce this with arecord?

What chipset are you on? Please provide both "lspci -v" and "lsusb -v" dumps. As I said, I fail to reproduce that issue on any of my machines.

All other applications can read from the USB audio without problems, it's just something in the way Adobe Flash polls my audio input which causes a crash.

Just video capture (without audio) works just fine in Adobe Flash.

Ok, so that pretty much rules out the host controller. I just wonder why I still don't see it here, and I haven't heard of any such problem from anyone else.

Some more questions:

• Which version of Flash are you running?

Google Chrome has its own version of Adobe Flash:

Name: Shockwave Flash Description: Shockwave Flash 11.4 r31 Version: 11.4.31.110

So that's the same that I'm using.

...

• Does this also happen with Firefox?

No, Adobe Flash in Firefox is an older version (Shockwave Flash 11.1 r102), it shows just two input devices instead of three which the newer Flash players sees.

• HDA Intel PCH
• USB Device 0x46d:0x81d

And that works, I assume? Does the second choice in the newer Flash version work maybe?

...

• Does flash access the device directly or via PulseAudio?

PA is not installed on my computer, so Flash accesses it directly via ALSA calls.

Ok, Same here.

...

• Could you please apply the attached patch and see what it spits out to

dmesg once Flash opens the device? It returns -EINVAL in the hw_params callback to prevent the actual streaming. On my machine with Flash 11.4.31.110, I get values of 2/44800/1/32768/2048/0, which seems sane. Or does your machine still crash before anything is written to the logs?

I will try it a bit later.

Yes, we need to trace the call chain and see at which point the trouble starts. What could help is tracing the google-chrome binary with strace maybe. At least we would see the ioctl command sequence, if the log file survives the crash.

As the usb list is still in Cc: - Artem's lcpci dump shows that his machine features XHCI controllers. Can anyone think of a relation to this problem?

And Artem, is there any way you boot your system on an older machine that only has EHCI ports? Thinking about it, I wonder whether the freeze in VBox and the crashes on native hardware have the same root cause. In that case, would it be possible to share that VBox image?

Daniel