Re: [PATCH 00/26] Dynamic kernel command-line

Martin Schwidefsky
2006-09-04T08:32:15Z

On Mon, 2006-09-04 at 12:50 +1000, Nigel Cunningham wrote:
> I agree. The current limit varies widely, most often being 256 or 512,
> but sometimes also 896 (s390!) or 1024 (arm, arm26, parisc) or 4096
> (uml). Would users and developers of those arches care to enlighten? Why
> 896?

Simple. Between 0x10480 and 0x10800 there are 0x380 bytes available.
That makes 895 characters for the commandline. Completly obvious, how
could you miss it ? ;-)
The reason is our initial address space layout for the very first kernel
images. Now it is hard to changed because the different ipl tools rely
on the layout. We choose to add a few more bytes than 256 because on
s390 we potentially have many devices. The dasd= parameter can really be
big.

--
blue skies,
Martin.

Martin Schwidefsky
Linux for zSeries Development & Services
IBM Deutschland Entwicklung GmbH

"Reality continues to ruin my life." - Calvin.

--
VGER BF report: H 0