Re: 2.4.20 st + aic7xxx (Adaptec 19160B) + VIA KT333 repeatable freeze

[Keith Owens <kaos@ocs.com.au>]

On Mon, 16 Dec 2002 14:52:26 +1100, 
caf@guarana.org wrote:
>Running with nmi_watchdog=2 has made the problem a bit harder to
>reproduce[1], but when it does hang it doesn't produce a trace (I left it
>for several minutes just in case..).  Checking /proc/interrupts after 
>boot shows around 16 NMIs, which I presume means that it's being used? -
>although it didn't seem to be going up at anything like once every 5
>seconds.

nmi_watchdog=2 should pop once per second, nmi_watchdog=1 pops HZ
(usually 100) times per second.  Anything less than once a second is
not working.  One possibility is CONFIG_X86_UP_APIC, it should be y for
UP to use nmi_watchdog.

>Is it possible that I'm not seeing the trace because I'm using a VGA
>virtual console rather than a real serial console?

Depends on your boot parameters for console and the levels of console
printk.  Console output to X is unlikely to work, output to VGA
(including virtual consoles) should work.  Except that some
distributions change printk levels and even redirect output to a
different virtual console.

cat /proc/cmdline should have no console setting or 'console=tty0'.
Change boot options and reboot if necessary.

cat /proc/sys/kernel/printk should report 6 4 1 7, if not then
echo "6 4 1 7" > /proc/sys/kernel/printk