[alsa-devel] Backported sbxfi driver (UNTESTED!)

[Takashi Iwai]

At Thu, 23 Oct 2008 19:15:26 +0200,
I wrote:
> 
> At Thu, 23 Oct 2008 19:07:40 +0200,
> I wrote:
> > 
> > At Thu, 23 Oct 2008 15:23:24 +0100,
> > Jason Harvey wrote:
> > > 
> > > Takashi Iwai wrote:
> > > > What is the last kernel message from sbxfi driver?
> > > > Usually it prints some messages (as debug=1 as default).
> > > >
> > > >   
> > > 
> > > I applied the patch and when trying "mplayer wn.wav" I consistently get 
> > > the following message on the console
> > > 
> > > PANIC: double fault, gdt at c13f6000 [255 bytes]
> > > 
> > > nothing else, either reboots instantly or locks up.
> > > 
> > > In case you might find it of use I modprobed at debug=3 and ran dmesg 
> > > before I ran mplayer. Output attached.
> > 
> > Thanks.
> > 
> > The last entries are:
> > 
> > > SBXFI: Setting TLB buffer page 0x1daff000
> > > SBXFI:   write(0) 0x13b004 = 0x1daff000
> > > SBXFI:   write(0) 0x13b000 = 0x0
> > 
> > Hm, this smells like a buffer handling issue.
> > 
> > I updated the sbxfi driver code now, added mutex around the code
> > handling TLB pages.
> > Please give it a try.
> 
> Another patch to try is the one like below (on the top of the latest
> code).  Any change with this?

One another thing I'm wondering is whether this happens only with
OSS.  What happens if you do like the following to disable the sample
rate conversion?

	# echo mplayer 0 0 direct > /proc/asound/card0/pcm0p/oss


Takashi