Re: [BUG?] cavium cn56xx and dma_map_single warning

[David Daney <ddaney@caviumnetworks.com>]

On 03/22/2010 06:30 PM, Zhuang Yuyao wrote:
> Thanks for your reply. Will this issue be solved soon? Is it a
> hardware issue or a software one?
A combination.  I think a Software fix is possible.

> Can I make the 4G-256M memory
> reserved so that kernel will not try to allocate memory in this area?
I have never tried it.

The issue is maintaining mappings for 32-bit PCI devices.  If you only 
want to support 64-bit devices, it would be easier to address the issue.
David Daney

> can not use more than 4G ram is bothersome since the memory is so cheap now. :-)
>
> Thanks very much.
>
> On Tue, Mar 23, 2010 at 12:44 AM, David Daney<ddaney@caviumnetworks.com>  wrote:
> > This is a known issue.
> >
> > passing mem==3072M will restrict kernel memory usage thus avoiding the
> > issue.
> >
> > David Daney