[ath9k-devel] Dirty Laundry List

[Alistair John Strachan <alistair@devzero.co.uk>]

On Thursday 20 November 2008 23:28:47 Luis R. Rodriguez wrote:
> On Thu, Nov 20, 2008 at 03:23:19PM -0800, Alistair John Strachan wrote:
[snip]
> > Why does this have to be a MacBook Pro 3.1? If the ath9k driver's got
> > swiotlb issues it should be possible to use any supported hardware in
> > combination with the sw-iommu right? The IOMMU can be forced on with
> > machines less than ~4GB, so just about anybody could test it.
>
> You would think right!? Have you seen the bug report?
>
> http://bugzilla.kernel.org/show_bug.cgi?id=11811

No, very interesting! Fortunately I was able to reproduce the problem on my 
2GB RAM Macbook v2, despite the experiences you guys have had.

I built a kernel (2.6.28-rc5) with SWIOTLB set, and then booted with 
"iommu=soft swiotlb=force mem=512M" and then copied a TV show onto the laptop 
from another computer. It broke almost instantly (and took some of my data 
with it :-)).

[snip]
> So we have patches now, so what we
> need is to see if it still occurs with such patches. If anyone has a
> MacBook pro 3.1 and is willing to test please let me know.

I applied the patches, re-ran my test case, and half a gig later the problem 
seems to be gone. So if this is any use to you at all I'd say it's fixed by 
those patches, which do make a lot of sense.

The driver tested was the one in 2.6.28-rc5. I had to apply the patch manually 
because the driver in 2.6.28-rc5 is formatted in a substantially different 
way. No functional differences afaict.

-- 
Cheers,
Alistair.