KeInsertQueueDpc locks up

In our interrupt handler, we call KeInsertQueueDpc to queue a dpc. When the system gets busy, after 10 to 30 minytes, it hangs. Using a debugger we found it is spinning on a spinlock (not one of ours) and when we clear the spinlock, everything works fine again.
This works fine on pre-Vista systems. Is there a known problem or change with this function?

Can you share the callstack?

In addition the OP should search for the thread that is holding the
spinlock. It should be on one of the cpus. That stack would be
interesting as well.

-----Original Message-----
[] On Behalf Of
Sent: Tuesday, March 20, 2007 12:54 PM
To: Windows System Software Devs Interest List
Subject: RE:[ntdev] KeInsertQueueDpc locks up

Can you share the callstack?

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