Subject: Re: renaming /boot to /boot_
To: Simon Burge <simonb@netbsd.org>
From: Chris G. Demetriou <cgd@netbsd.org>
List: tech-kern
Date: 09/30/1999 00:16:06
Simon Burge <simonb@netbsd.org> writes:
> That was one question I had about the alpha.  Is the area _before_ the
> bootblock info and the end of sector 0 available for code?  On the pmax,
> we really have a 8k-64 limit on code size, not 7.5k, but obviously this
> makes sharing sector 0 almost unmanagable.

No.  IIRC, block 0 is not even loaded into memory in a well-defined
place.

Alpha can use a lot more than 7.5KB for the primary, but if you want
to fit into the space before an FFS superblock you're limited to 7.5K


> I saw this comment before and my first thought was "why?". libsa
> currenly can open a maximum of SOPEN_MAX (4) files.  Just a plain
> subdirectory scanner doesn't use open files, and my bit of pseudocode
> 
> 	if open("/boot/${MACHINE}") fails
> 		if open("/boot") fails
> 			die
> 
> only uses two of these at worst case...

Uhh, actually, it should use only one, eh?

upon further reflection, i think the 'close' issue is a red herring.

however, there's still the issue of consistency.  There's no reason
the bootxx_* blocks should look for different secondaries, and at
least the LFS boot blocks _can't_ cope with the sudir.  It's annoying
to explain clearly, and will only lead to confusion.  "but it was
there on the CD-ROM, why can't i boot from my hard disk?" is a very,
very bad place for a user to be.



cgd
-- 
Chris Demetriou - cgd@netbsd.org - http://www.netbsd.org/People/Pages/cgd.html
Disclaimer: Not speaking for NetBSD, just expressing my own opinion.