panic in RELENG_5 UMA - two new stack traces

[Gary Mu1der]

Gleb Smirnoff wrote:
> On Tue, Jun 28, 2005 at 11:24:47AM -0400, Gary Mu1der wrote:
> G> I spent the day yesterday trying to reproduce the crash that I posted 
> G> last week and you kindly replied to. This is due to the fact that I 
> G> stupidly managed to overwrite the kernel.debug that I used to generate 
> G> the stack trace. Sadly I could not cause the system to crash again with 
> G> the same sb* errors.
> G> 
> G> I did however remove both the Berkley Packet Filter and IPFilter from my 
> G> custom kernel to try and isolate the problem. This has caused the crash 
> G> to occur in a different and more reproducible form. I have both 
> G> INVARIANTS and WITNESS enabled, as you can see from my kernel conf. 
> G> which is included at the end of this e-mail.
> G> 
> G> Below are the latest stack traces (using bge and then fxp NICs), kernel 
> G> conf. and dmesg. Any help would be appreciated. This time I have a copy 
> G> of both the core files and corresponding kernel.debug so I can hopefully 
> G> provide you with any info you need.
> 
> How often does it crash? Does debug.mpsafenet=0 increases stability?

I can reproduce the crash within 60 seconds of firing off 30+ ping/arp 
-d scripts, all running in parallel.

debug.mpsafenet=0 seems to have solved the problem. I'm running 100+ 
instances of the above script and the system has been stable for over an 
hour.

As I wanted some background on what "debug.mpsafenet=0" does, I did some 
Googling and found a good write up here:

http://unix.derkeiler.com/Mailing-Lists/FreeBSD/current/2004-08/2280.html

Thanks,
Gary