lkml.org 
[lkml]   [1998]   [Oct]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Cyrix Detection -- NO SMP, please ?????
On Sun, 18 Oct 1998, Khimenko Victor wrote:

> In <3629E2F2.B1A546D4@nb.net> Rob Dale (rob@nb.net) wrote:
> RD> Khimenko Victor wrote:
> >>
> >> GM> First off, before you get all hot and bothered: SMP=1 SHOULD BE OFF BY
> >> GM> DEFAULT!. No one SHOULD be running a SMP kernel on a non SMP box! Yes, it
[...]
>
> RD> This is a distribution issue, not a kernel issue.
>
> No. It's kernel issue. Installation CD has image of ONE, EXACTLY ONE floppy
> (1.44" -- even 2.88" not supported by all BIOS'es). Since this floppy MUST
> include kernel and all drivers needed to obtain access to CD this effectively
> means that this floppy could include EXACTLY ONE kernel -- SMP one since we
> must detect SMP :-)


You seem to be missing something here, the kernel image the install
CD/floppy boots in not necessarily the image that will go into the new
Linux installation. The distribution installer program can choose later
on the most appropriate image from the CD and copy it to the hard drive.

Also, we don't need an SMP kernel to detect SMP, just a setuid root
program that can probe a few IO ports around the system. This is not
optimal but making SMP 100% realiable under UP is hard and not a priority
of the SMP developers, and understandably so: it is agreed that "you
shalt not run SMP on UP" since performance will suck.

Lastly, Linus has said (and it has been repeated a zillion times) that the
current SMP=1 line in the 2.1.x Makefile is just a convenience for him and
will go away on 2.2. So yes, SMP=1 *is* off by default.


> >> Dists should select right kernel automatically in most cases. Windows NT do
> >> this for last few years -- why Linux could not do this ? "Joe Average" viewpoint
> >> of course :-))
> >>
>
> RD> Look at what you said: Dists should select...
> RD> That's exactly right! The distributions should do it.
> RD> Not the kernel. This has nothing to do with the kernel.
>
> You are wrong. It's kernel issue.
> 1. BEFORE distribution will select ANYTHING installation program MUST be
> able to start. Since installation program is program for Linux.


Simple, Boot an UP kernel, that should work on all setups, both UP and
SMP.


> 2. [Almost] All features MUST be turned on by default. For one or two (SMP?)
> distribution could produce special versions. Distribution COULD not include

Not true, all features *essential* to installing the distro. must be
enabled. This means just access to the CDROM and hard disk (and maybe the
network). But not multicasting, APM, frame-buffer, sound, and all other
extras. Think of it as booting into the dreaded Win95 safe mode. Once
the hardware has been identified the a proper non-conflicting image can be
selected. It is a distribution issue.

Cheers,

Rafael


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

\
 
 \ /
  Last update: 2005-03-22 13:45    [W:0.090 / U:0.072 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site