Re: System crash after "No irq handler for vector" linux 2.6.19

[ebiederm@xmission.com (Eric W. Biederman)]

"Luigi Genoni" <luigi.genoni@pirelli.com> writes:

> reproduced.
> it took more or less one hour to reproduce it.  I could reproduce it olny 
> running also irqbalance 0.55 and commenting out the sleep 1. The message in 
> syslog is the same and then, after a few seconds I think, KABOM! system crash 
> and reboot.
>
> I tested also a similar system that has 4 dual core CPU Opteron 2600MHZ. On 
> this system (linux sees 8 CPU, but it is the same kernel, same gcc, same 
> config, same glibc, same active services) I could not reproduce it even 
> running irqbalance 0.55 in almost 1 hour. Maybe I could reproduce it waiting 
> for more time, but my users need to do their work, so I could not have a 
> longer test window. So on 16 CPU I had the crash, on 8 CPU I had no crash. 
>
> I need to give back the system to the users, so if you need other tests, 
> please, tell me as soon.

Ok.  Since it seems to be the irq code I'm going to need to get a dump
of the state of the apics, basically the output print_IO_APIC from the time
this happens. 

I'm not really out of bed yet so no patch but a heads up.  Once I've finished
sleeping I'll look at putting a debugging patch together.

Getting a bootlog of the identical system that would not crash at 8 cpus
would be interesting.  In part this is because the number of apic modes
that are available for use are much fewer when we have 8 or more cpus,
so it would be interesting to see if it is actually using the same code
for interrupt delivery.

If you have a few minutes to try it, it would be interesting to know
if forcing the migration from the command line (as I was suggesting)
would reproduce this faster than irqbalance.

Hopefully I can think up things to fix this when I wake up.

The time zone difference is going to be a pain :(

Eric