Re: 2.5.59-mm6

[Mike Galbraith]

At 01:27 PM 1/27/2003 +0100, Luuk van der Duim wrote:
>Hello mm-users,
>
>
>   . The mysterious "machine hangs late in boot" problem has been narrowed
>     down thanks to some great work by Andres Salomon.  The machine is stuck
>     waiting on I/O completion when performing the initial lookup for
>     /sbin/devfs_helper:
>
>
>I don't believe it to be an exclusively small-devfs helper problem.

Well, my test box agrees (I have never ever used devfs, but could lock hard 
in minutes)  mm6 works fine here, so I _think_ it's probably resolved...

>It is an interaction at best. Sure I had problems using devfs-small, but
>mm2 worked and mm3 was the first that halted during boot. Both have
>devfs-small, and both need its helper. Or I am missing a subtlety here?

I don't think you're missing anything, but I also don't know wtf the 
interaction is.  I put a couple of man-days into looking for it, and came 
up with exactly nada of interest.

>Secondly, Andrew sent me a rollup of patches against 2.5.59 he thought
>were suspicious, without smalldevfs and it also halted, but at another
>place in boot, at adding swap.

Mine locked hard hard hard.  Booted fine, but died reliably under heavy load.

(something seems funky with nmi_watchdog... hard lock = no_more_nmi_ticks 
.  Anybody out there know enough about local APIC to explain why idle=poll 
gives nice 1 second nmi, but everything else depends upon cpu load?... and 
why when hardlock happens, it _stops_)

>Can someone besides me confirm this behavior or am I the loon who just
>won't understand?

My box agrees that you're not a loon fwTw :)

         -Mike