Re: [discuss] Re: x86_64: 2.6.14-rc4 swiotlb broken

[Ravikiran G Thirumalai <kiran@scalex86.org>]

On Mon, Oct 17, 2005 at 09:09:52PM +0200, Andi Kleen wrote:
> On Monday 17 October 2005 21:04, Linus Torvalds wrote:
> 
> > So the only thing that worried me (and made me ask whether there might be
> > machines where it doesn't work) is if some machines might have their high
> > memory (or no memory at all) on NODE(0). It does sound unlikely, but I
> > simple don't know what kind of strange NUMA configs there are out there.
> 
> It could happen in VirtualIron (they seem to interleave node 0 over many nodes 
> to get equal use of lowmem in 32bit NUMA), but should not in x86-64..
>  
> > And I'm definitely only interested in machines that are out there, not
> > some theoretical issues.
> 
> According to Alex W. it will break their sx1000 IA64 boxen.

sx1000 is probably already broken;  Unless the last pgdat happens to be the
memory only node with 0-4G?  How about the fix I suggested which would iterate 
across all nodes until it found the right node for swiotlb?

Thanks,
Kiran