lkml.org 
[lkml]   [2002]   [Dec]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Reserving physical memory at boot time
On Wed, 4 Dec 2002, Richard B. Johnson wrote:

| On Wed, 4 Dec 2002, Mike Galbraith wrote:
|
| > At 08:25 AM 12/4/2002 -0500, Richard B. Johnson wrote:
| > >On 3 Dec 2002, Alan Cox wrote:
| > >
| > > > On Tue, 2002-12-03 at 21:11, Richard B. Johnson wrote:
| > > > > If you need a certain page reserved at boot-time you are out-of-luck.
| > > >
| > > > Wrong - you can specify the precise memory map of a box as well as use
| > > > mem= to set the top of used memory. Its a painful way of marking a page
| > > > and it only works for a page the kernel isnt loaded into.
| > > >
| > >
| > >If you are refering to the "reserve=" kernel parameter, I don't
| > >think it works for memory addresses that are inside existing RAM.
| > >I guess if you used the "mem=" parameter to keep the kernel from
| > >using that RAM, the combination might work, but I have never
| > >tried it.
| >
| > reserve= is for IO ports (kernel/resource.c). I think Alan was referring to
| > mem=exactmap.
| >
| > If Duncan didn't have the pesky requirement that his module work in an
| > unmodified kernel, it would be easy to use __alloc_bootmem() to reserve an
| > address range and expose via /proc. But alas...
| >
|
| Well that parameter is not documented in:
|
| .../linux-2.4.18/Documentation/kernel-parameters.txt.
|
| Perhaps it's a 2.5.++ thing.

Patch for 'mem=exactmap' in 2.4 was submitted several weeks ago and
Alan merged it into -ac. It does need to be pushed to Marcelo...

--
~Randy

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:31    [W:0.116 / U:0.316 seconds]
©2003-2011 Jasper Spaans