Subject: Re: CVS commit: src/sys/arch
To: Izumi Tsutsui <tsutsui@ceres.dti.ne.jp>
From: David Laight <david@l8s.co.uk>
List: tech-kern
Date: 11/08/2006 22:18:36
On Wed, Nov 08, 2006 at 10:11:45PM +0900, Izumi Tsutsui wrote:
> 
> BTW, is it really worth to check about overwriting disklabel
> in bounds_check_with_label()? I guess it's almost the only reason
> why RAW_PART shall be 3 (D partition) on ports which support MBR,
> and some ports (macppc etc.) don't have the check.

AFAICR the only place that the 'c' partition is used in i386 is in
the check against overwriting the disklabel.
The kernel also sets 'c' to be the mbr partition where it found the label,
regardless of the label contents.
(I can't remember what happens when the label comes from sector 0 of
the disk.)

I've sometimes thought that this is pointless, and the 'label-sector'
should be remembered by other means.  That would free up 'c' - so it
could be used to represesnt the 'd' partition of disks from systems
where 'd' is a user partition....

	David

-- 
David Laight: david@l8s.co.uk