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

[Alex Williamson <alex.williamson@hp.com>]

On Tue, 2005-10-18 at 16:04 -0600, Alex Williamson wrote:
> On Tue, 2005-10-18 at 14:53 -0700, Ravikiran G Thirumalai wrote:
> > On Tue, Oct 18, 2005 at 03:28:27PM -0600, Alex Williamson wrote:
> > > So, it looks like we're iterating over the nodes, but
> > > alloc_bootmem_node() isn't even guaranteed to try to get memory from the
> > > low memory on that node.
> > 
> > Thanks Alex. 2.6.14-rc4-mm1 already has the 
> > guarantee-dma-area-for-alloc_bootmem_low.patch by Yasunori-san.  So it is 
> > safer to confirm results on latest 2.6.14 stock.
> 
>    Ok. I'll need to build a stock tree then.
> 

   Nope, it breaks with a current git-2.6.14.  Here's what my extra
printk says:

Node 0: 0xe000074104e67200
Node 1: 0xe000082080722000
Node 2: 0xe000000101532000
Placing software IO TLB between 0x74108e68000 - 0x7410ce68000

So same scenario as on -mm w/ the iterating across nodes, but now
alloc_bootmem_low_pages() doesn't catch us in the end.  This will fail
in any case where MAX_DMA_ADDRESS is 4GB and every node has memory
sufficient for the swiotlb size above 4GB.  Thanks,

	Alex