Losing Interrupts with 5.2RC & ACPI

I have a fairly new AMD nforce2 based machine running 5.2RC (updated
from RELENG_5_1 to RELENG_5_2 a couple of days ago) that has been
working perfectly with ACPI enabled, although there are a couple of ACPI
related error messages on bootup.The machine has been running for a
month or so using the internal nv0 ethernet but has also had an fxp0
interface sitting unused. So today I decided to setup a DMZ on the fxp
card and ran into immediate problems with interrupts.

Both interfaces share the same interrupt, and work fine without ACPI
enabled, but if ACPI is enabled they will both start issuing watchdog
timeouts within about 30sec of completing bootup, during which time
vmstat -i shows no new interrupts at all on the shared irq.  If I down
the fxp0 interface during this the nv0 interface seems to recover after
the watchdog timer expires (I didn't try up'ing the fxp0 interface
again).

Any suggestions on where to start looking or options to turn on to try
and track down what's going on?

-- 

Seeya...Q

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                          _____  /   Quinton Dolan q_dolan_at_yahoo.com.au
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