Interrupt storm with shared interrupt on digi(4)

[Peter Jeremy]

I have an on-going problem with DigiBoard Xem boards causing interrupt
storms (since 4.x days).  The FreeBSD driver polls the board and
doesn't have a functional interrupt handler (and Linux behaves in the
same way).  It seems that under some conditions, the board will assert
its interrupt line and, since there's no interrupt handler to clear
whatever triggered the interrupt, the IRQ is never unasserted.

In the past, I have managed to avoid the problem by putting the Digi
card on a dedicated interrupt.  For reasons I don't understand, this
appears to mask the problem.

Unfortunately, I now have a system where, courtesy of Compaq's
incompetence, I have no way to avoid having two Digi boards sharing an
interrupt.  In 7.x, as soon as I load digi.ko, I get "interrupt storm"
messages.  In 6.x, I could see the interrupt storm but it didn't
flood my console with messages.

Does anyone have a patch that will generate an appropriate EOI to
a DigiBoard?

Alternatively, can anyone suggest how I can disable or mask a specified
PCI interrupt?

-- 
Peter Jeremy
Please excuse any delays as the result of my ISP's inability to implement
an MTA that is either RFC2821-compliant or matches their claimed behaviour.
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