Rogue IRQ blows up irqbalance

[Jay Cliburn]

I haven't reported this to the linux-kernel folks yet, but I have a 
system (Asus M2V dual-core Athlon) whose audio device gets assigned an 
IRQ of 8410 in 2.6.18-rc5-mm1.  (Works fine in rc4-mm3, getting assigned 
an IRQ of 17.)  This causes irqbalance to segfault at line 108 of 
procinterrupts.c because interrupts[irqnumber] goes off into space, 
since irqnumber is larger than MAX_INTERRUPTS (256).

Would it be worthwhile to add a sanity check on the irqnumber read up 
from /proc/interrupts?

Jay