kernel panic

[Matthew Dillon]

:I updated to the latest HEAD as of yesterday (2007-05-09) after the
:INET6 fix.  
:
:...
:I got the following kernel panic:
:
:Fatal trap 19: non-maskable interrupt trap while in kernel mode
:mp_lock = 00000000; cpuid = 0; lapic.id = 00000000
:instruction pointer     = 0x8:0xc02f6a1e
:stack pointer           = 0x10:0xcade4a44
:frame pointer           = 0x10:0xcade4a68
:...
:processor eflags        = interrupt enabled, IOPL = 0
:current process         = 729 (ifconfig)
:current thread          = pri 6 
: <- SMP: XXX
:
:It looks like the stack was corrupted but I was able to get this:
:
:(kgdb) bt
:#0  0x00000000 in ?? ()
:(kgdb) info locals 
:No symbol table info available.
:(kgdb) x 0xc02f6a1e
:0xc02f6a1e <agp_intel_flush_tlb+35>:    0x81028b90
:
:I can upload the kernel and vmcore files if absolutely necessary but
:the vmcore file is 1.6GB uncompressed so if I don't need to I will
:save the bandwidth.
:
:Perhaps unrelated, but just in case.  I got this out of the kernel
:buffer:
:
:[diagnostic] cache_lock: blocked on 0xdc583e28 "utils"
:
:I have also had a cvs process hang in the "vnode" state.  I was unable
:to attach the process with gdb (this just seemed to hang) or get any
:output from ktrace.
:
:Thanks,
:Joe Talbott

    NMI traps during device operation usually indicate a bus parity
    failure during DMA.  This often occurs when shared memory on
    the device itself is not properly initialized by the device driver
    and then accessed.

    What interface were you ifconfig'ing when the crash occured?
    And is it repeatable?

					-Matt
					Matthew Dillon 
					<dillon at backplane.com>