[alsa-devel] USB transfer_buffer allocations on 64bit systems

[Daniel Mack]

On Mon, Apr 12, 2010 at 02:12:43PM +0200, Andi Kleen wrote:
> > I'm not putting into question whether something is broken in my
> > system, but if it is, it must be the ICH9 platform, because I was able
> > to reproduce it in another laptop.
> > 
> > My laptop is a Lenovo T400 and I was able to reproduce it in a Acer
> > Aspire 59xx (I don't remember the exact model, but it is one of the
> > new ones with 15.6 inch - i think they all use the same base). And the
> > common thing between them is the ICH9 platform.
> 
> There are lots of systems around with ICH9 that work fine.
> I'm typing on one.

FWIW, the fix that made it work for Pedro was to use usb_buffer_alloc()
for the transfer_buffer of the audio module.

Another detail I can't explain is that on his machine, the kernel oopses
when kmalloc() with GFP_DMA32 is used. The patch to try this also only
touched the allocation in sound/usb/caiaq/audio.c.

> > The only which solved this problem was the first patch sent to me by
> > Daniel Mack. I've been using it for days straight and it works fine.
> 
> Can you send a full boot log?

He just did. I put it online here:

  http://caiaq.de/download/tmp/pedro-dmesg

Daniel