Bug #2308

System freeze when unloading snd_hda

Added by jaydg over 2 years ago. Updated over 2 years ago.

Status:NewStart date:02/17/2012
Priority:NormalDue date:
Assignee:-% Done:

0%

Category:-
Target version:-

Description

When unloading snd_hda, the system (v3.1.0.197.gcc1635-DEVELOPMENT) freezes completely.
There is no panic; the screen just gets garbled and the system no longer responds to any interaction, may it be local or via network.

This shows up when loading the module:

pcm0: <NVidia MCP51 High Definition Audio Controller> mem 0xf2300000-0xf2303fff irq 21 at device 16.1 on pci0
pcm0: <HDA Codec: Realtek ALC260>
pcm0: <HDA Driver Revision: 20071129_0050>

DSC00003.JPG (422 KB) jaydg, 02/19/2012 07:15 AM

History

#1 Updated by herrgard over 2 years ago

On Fri, Feb 17, 2012 at 11:36:58PM -0800, Joachim de Groot via Redmine wrote:
> When unloading snd_hda, the system (v3.1.0.197.gcc1635-DEVELOPMENT) freezes completely.
> There is no panic; the screen just gets garbled and the system no longer responds to any interaction, may it be local or via network.

Are you in X? If you are, try from console.

You could also try debug.debugger_on_panic set to 0. This will make your box
panic insead of going into the debugger.

Max

#2 Updated by jaydg over 2 years ago

The effects are the same whether X is started or not. Setting debug.debugger_on_panic has no effect, the system just freezes. I've attached a "screen shot" of a garbled console screen.

While trying this out, I found two other variations of this:

2) Module doesn't find sound card at first, system freezes at the second attempt to load the module:

root@deimos:~ # kldload snd_hda
pcm0: <NVidia MCP51 High Definition Audio Controller> mem 0xf2300000-0xf2303fff irq 21 at device 16.1 on pci0
pcm0: Audio Function Group not found!

root@deimos:~ # kldunload snd_hda
pcm0: detached

root@deimos:~ # kldload snd_hda

==> freeze

3) Sort of a interrupt conflict when loading the module:

pcm0: <NVidia MCP51 High Definition Audio Controller> mem 0xf2300000-0xf2303fff irq 21 at device 16.1 on pci0
pcm0: <HDA Codec: Realtek ALC260>
pcm0: <HDA Driver Revision: 20071129_0050>
intr 18 on cpu0 at 40001/40000 hz, livelocked limit engaged!

And then keyboard and mouse are no longer usable as interrupt 18 is occupied by the usb controller:
ohci0: <OHCI (generic) USB controller> mem 0xf2304000-0xf2304fff irq 18 at device 11.0 on pci0

When unloading the module via ssh, the system freezes as usual.

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