I need some help tracking down an old bug

[Bruno Wolff III]

I had a bug introduced between kernel-2.6.29.1-68.fc11 and 
kernel-2.6.29.1-69.fc11 that I am trying to track down. It looks like 
the obvious change between these two kernels is dropping a patch 
that is for a wireless module and the machine I am having the issue 
on doesn't have wireless. The issue is a hard lockup that occurs when 
playing motherboard sound with signiificant network traffic and both 
processors (Athlon XMPs) enabled. It doesn't seem like that patch should 
effect that unless it triggers some different code to compile differently.

I looked at the root logs for those builds and they both use the same gcc. 
The kernel headers package is different, but I wouldn't expect a kernel 
build to use the installed version of kernel headers. (I want to check 
for differences there just in case, but haven't gotten to it.) 
e2fsprogs-libs also changed versions, but it seems like a long shot that 
that is what triggered the problem.

I have built a vanilla 2.6.29 kernel in an f11 chroot (with f11 updates 
installed) and am seeing the problem. I have also seem the problem in 
some other kernels built between 2.6.28 and 2.6.29 also built in that 
environment.

Some other steps I am considering are downgrading gcc or setting up an 
f10 environment and trying to build vanilla kernels there.

I haven't ever been able to get a crash dump when this problem hits, so 
debugging it with current kernels is pretty hard. I was hoping to find the 
change that triggered the problem and that that would provide a good clue 
as to what the problem is.

Any suggestions for how to continue pursuing this?