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From: Matthew Dillon <dillon@apollo.backplane.com>
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Subject: Re: Potential source of interrupt aliasing
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:    Hmm.  I can think of two solutions that avoid masking:
:
:    * Change the trigger mode from level to edge as a means of masking the
:      interrupt, then change it back to level triggered to unmask.  This
:      would be done in the IO APIC.
:
:    * Change the delivery mode to low-priority for the interrupt that occured
:      and use the priority field to mask the interrupt to the cpu.  This
:      would be done in the IO APIC with the LAPIC's TPR set appropriately.

    Here's a third... mess with the IOART_DEST mask for the pin on the 
    IOAPIC.  Can it be set to not route the interrupt to *any* cpu ?  
    Usually it's set to broadcast (all bits 1, at least on 4.x and DragonFly).

    so. e.g. IOART_DESTPHY but then with no cpu specified in IOART_DEST.

					-Matt
					Matthew Dillon 
					<dillon@backplane.com>