Subject: Re: BUG-REPORT Re: ml403 ac97 driver

From: Joachim Förster <[email-masked]>
Date: Thu, 09 Aug 2007 19:01:42 +0200

Hi Qin Lin,

sorry for my late answer.

On Tue, 2007-07-31 at 04:49 -0700, Qin Lin wrote:
> When i used the aplay to test the drive first time,it played well. But 
> after restart the board 
> it is not well again.

Well, I don't think the problem occurs due to the restart of your
board ...

> # aplay yonggan.wav
> Playing WAVE 'yonggan.wav' : Signed 16 bit Little Endian, Rate 44100 Hz,
> Stereo
> [  258.518119] Kernel stack overflow in process c039ec00, r1=c3e0bf50

... but unfortunately I can't tell how such an error results from the
driver. Are you able to reproduce it?
Since the driver "works", I never got such an error nor another kernel
panic/error.

[The only thing that comes to my mind is the very high interrupt volume,
because of the very small size (32 byte) of the playback FIFO (of the
AC97 controller) => hardware issue. But, since interrupts are _disabled_
during execution of interrupt handlers, I am sure that this cannot be
the source of the problem.]

 Joachim