2002-01-21 06:27:11

by Richard Gooch

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Subject: Boot hang in 2.5.3-pre2

Hi, Linus. FYI: 2.5.3-pre2 hangs during boot. The last couple of
messages I get are:
Based upon Swansea University Computer Society NET3.039
apm: BIOS version 1.2 Flags 0x03 (Driver version 1.15)
apm: disabled - APM is not SMP safe (power off active).

Going back to 2.5.2, the next boot line is:
Starting kswapd

Regards,

Richard....
Permanent: [email protected]
Current: [email protected]


2002-01-21 12:29:18

by Dave Jones

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Subject: Re: Boot hang in 2.5.3-pre2

On Sun, Jan 20, 2002 at 11:26:42PM -0700, Richard Gooch wrote:
> Hi, Linus. FYI: 2.5.3-pre2 hangs during boot. The last couple of
> messages I get are:
> Based upon Swansea University Computer Society NET3.039
> apm: BIOS version 1.2 Flags 0x03 (Driver version 1.15)
> apm: disabled - APM is not SMP safe (power off active).

Ingo's scheduler patches solved this one for me (and others).

--
| Dave Jones. http://www.codemonkey.org.uk
| SuSE Labs

2002-01-21 12:33:08

by Ingo Molnar

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Subject: Re: Boot hang in 2.5.3-pre2


On Mon, 21 Jan 2002, Dave Jones wrote:

> > Hi, Linus. FYI: 2.5.3-pre2 hangs during boot. The last couple of
> > messages I get are:
> > Based upon Swansea University Computer Society NET3.039
> > apm: BIOS version 1.2 Flags 0x03 (Driver version 1.15)
> > apm: disabled - APM is not SMP safe (power off active).
>
> Ingo's scheduler patches solved this one for me (and others).

it's the migration-fixes-2.5.3-pre2-A1 sub-patch of the -J2 scheduler
patch, just in case someone wants to apply a minimal patch.

Ingo

2002-01-21 12:41:10

by Ingo Molnar

[permalink] [raw]
Subject: Re: Boot hang in 2.5.3-pre2


On Mon, 21 Jan 2002, Dave Jones wrote:

> > Hi, Linus. FYI: 2.5.3-pre2 hangs during boot. The last couple of
> > messages I get are:
> > Based upon Swansea University Computer Society NET3.039
> > apm: BIOS version 1.2 Flags 0x03 (Driver version 1.15)
> > apm: disabled - APM is not SMP safe (power off active).
>
> Ingo's scheduler patches solved this one for me (and others).

the bug is the following: the 2.5.3-pre2 kernel in essence includes the
-I3 patch. The -I3 scheduler doesnt have the task migration fixes yet, but
has the improved load-balancer. And exactly this improved load-balancer
makes task-migration much more likely to happen during bootup =>
triggering it for ksoftirqd migration, resulting in a hang.

older versions had the migration bug as well, but the first iteration of
the load-balancer was much less accurate at balancing runqueues, so it
didnt trigger the bug.

Ingo