Hard lockup with 2.4.18-pre9 + preempt + lock break + O1k[23] + rmap

[Mike Fedyk]

On Fri, Feb 15, 2002 at 08:37:52AM -0500, Robert Love wrote:
> On Fri, 2002-02-15 at 03:51, Robert Jameson wrote:
> > I have been seeing this oops from 2.4.16 -> 2.4.18-pre9, so here we go!
> 
> Do you see this on device close?  It looks like there may be a race
> between device closer -> usb release.
> 

I don't use USB, and I have had several machines lock up hard while doing
medium to heavy IO.  I've had this happen with pre9-mjc2 and another patch
that just contained pre9-preempt-schedo1
(nyu.dyn.dhs.org:8080/patches/2.4.18-pre9-to-rmap12e-schedO1-rml.patch.bz2)

I'm running 2.4.18-pre9-ac3 now to see if I can reproduce without prempt and
O(1).

I have someone else from IRC that has the same issue with prempt+O(1)
against vanilla 2.4.17.  He should be sending you a bug report soon.

BTW, all machines ran the same kernel compiled for SMP, but some machines
were UP.

Has anyone else seen this?

Mike