[alsa-devel] SB X-Fi driver fixes (Re: Testers wanted: New SB X-Fi driver)

[Takashi Iwai]

At Tue, 09 Jun 2009 07:44:29 +0200,
Gernot Kohlhaas wrote:
> 
> Takashi Iwai schrieb:
> > At Tue, 09 Jun 2009 07:23:56 +0200,
> > Gernot Kohlhaas wrote:
> >> Takashi Iwai schrieb:
> >>> Also, do you mean that the default output works without 1/3 second
> >>> distortion?  Or, the distortion happens regardless of your PCM device
> >>> setup?
> >>>
> >>> I'd like to concentrate on debugging the default setup at first,
> >>> so better to reduce the risk of brokenness of ladspa plugin.
> >>> If you get any severe problems with the default setup, please let me
> >>> know more details.
> >>>
> >>>
> >>> thanks,
> >>>
> >>> Takashi
> >>>
> >> No, this distortion happens "everywhere" when I compile the module with
> >> --debug=full.
> > 
> > That's weird.  Do you get any kernel messages?
> > 
> Unfortunately not. Just the "standard" ones (when loading the module).

Hm, please double-check later.  I really don't see any possible cause
of this.

> >> For the crashes: They only happen when I use the LADSPA low pass filter
> >> AND when I am fast forwarding in xmms. When I don't use fast forwarding,
> >> everything works fine. But I will try use_system_timer=1 when I get back
> >> from work today.
> >> It really seems like the plug-in is doing some weird stuff.
> > 
> > But the plugin itself cannot lead to a system crash.  It's the driver.
> > 
> > Do I understand correctly that your system locks up when this happens,
> > right?  If yes, the cause might be the mmap mode access.
> > 
> Yes, it locks up. No kernel panic or something like that. A "hard"
> lock-up/freeze.

OK, this implies either a spin deadlock or a dead-end in the irq
handler.

Anyway, please try the very latest alsa-driver-snapshot.  If it still
doesn't work, let me know whether use_system_timer=1 works around the
crash.  If yes, just try to comment out all spin_*() calls in
cttimer.c.


thanks,

Takashi