Subject: Re: Announce: DEC AlphaServer 8400 is coming
To: Jason Thorpe <thorpej@shagadelic.org>
From: Michael L. Hitch <mhitch@lightning.msu.montana.edu>
List: port-alpha
Date: 07/27/2005 23:11:34
On Wed, 27 Jul 2005, Jason Thorpe wrote:
> > SGMAP_DEBUG. What appears to be happening is that a spill page is
> > loaded in the sgmap_load routine, but the sgmap_unload routine doesn't
> > account for the spill page. Now to try to figure out why.
>
> Lemme take a look at the code and see if I can see anything. It'll
> be a good diversion while I burn CDs for a drive down to LA I have to
> do after work tomorrow.
Aha - I see what happened, but not why yet. The sgmap_load checks the
flags passed as an argument for BUS_DMA_READ being zero, an the
sgmap_unload checks the flags in map->_dm_flags. The problem occurs when
BUS_DMA_READ is cleared in the passed argument, but is set in
map->_dm_flags. I don't know why that is yet.
--
Michael L. Hitch mhitch@montana.edu
Computer Consultant
Information Technology Center
Montana State University Bozeman, MT USA