[PATCH v3 -next] Documentation: Improve crashkernel= description

Ahmed S. Darwish
2011-02-07T16:02:51Z

On Mon, Feb 07, 2011 at 09:25:50AM -0500, Vivek Goyal wrote:
> On Mon, Feb 07, 2011 at 01:30:54PM +0200, Ahmed S. Darwish wrote:
> >
> > Had to explore two C code files to make sense of the 'crashkernel='
> > kernel parameter values. Improve the situation.
> >
>
> Did you look at Documentation/kdump/kdump.txt before looking into the
> code. I thought kdump.txt explained the meaning of crashkernel= well.
>
> In case if it was not obivious that for further details look into
> kdump.txt, I will suggest to add a line asking reader to look into
> kdump.txt for more details.
>

Yes, I jumped to the code first :-) Here's a new patch with the link:

(Also applicable over latest -rc3)

==>

Complete the crashkernel= kernel parameter documentation.

Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
---

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 89835a4..050b0e5 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -545,16 +545,20 @@ and is between 256 and 4096 characters. It is defined in the file
Format:
<first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]

- crashkernel=nn[KMG]@ss[KMG]
- [KNL] Reserve a chunk of physical memory to
- hold a kernel to switch to with kexec on panic.
+ crashkernel=size[KMG][@offset[KMG]]
+ [KNL] Using kexec, Linux can switch to a 'crash kernel'
+ upon panic. This parameter reserves the physical
+ memory region [offset, offset + size] for that kernel
+ image. If '@offset' is omitted, then a suitable offset
+ is selected automatically. Check
+ Documentation/kdump/kdump.txt for further details.

crashkernel=range1:size1[,range2:size2,...][@offset]
[KNL] Same as above, but depends on the memory
in the running system. The syntax of range is
start-[end] where start and end are both
a memory unit (amount[KMG]). See also
- Documentation/kdump/kdump.txt for a example.
+ Documentation/kdump/kdump.txt for an example.

cs89x0_dma= [HW,NET]
Format: <dma>

>
> Acked-by: Vivek Goyal <vgoyal@redhat.com>
>

thanks,

--
Darwish