Re: [BUG/WARNING?] 2.5.57 ALSA sound/core/pcm_lib.c

[Takashi Iwai <tiwai@suse.de>]

At Wed, 15 Jan 2003 01:27:37 +0100 (CET),
Martijn Uffing wrote:
> 
> Ave people.
> 
> In 2.5.57 I get a bug/warning  when I'm using xmms. Xmms is configured for 
> OSS output,and the kernel is configured for ALSA sound including OSS emulation.
> 
> The following message is found in dmesg.
> "ALSA sound/core/pcm_lib.c:123: Unexpected hw_pointer value (stream = 0, 
> delta: -280, max jitter = 8192): wrong interrupt acknowledge? "
> I tried to reproduce the error and got another one. Only know the 
> delta 
> is -1008.
> 
> I didn't notice this messages until I looked in dmesg. So no hickup or 
> something from xmms. The song played fine.
> So the question is: Is this just a warning or a bug?

the message appears when the period (fragment) has not been processed
enough fast as expected.  a typical reason is the delay of hardware
interrupts, but this could be, of course, a bug of the driver, too.

this would be a bit problem if the application uses small numbers of
periods.  but in the case of xmms, it won't be serious.
if you don't see such a message not too often, you can ignore it...
(at least, i've never heard about this kind of bug on ens1371 driver.)

-- 
Takashi Iwai <tiwai@suse.de>		SuSE Linux AG - www.suse.de
ALSA Developer				ALSA Project - www.alsa-project.org