Re: [KVM PATCH 1/2] KVM: Directly inject interrupts via irqfd

[Avi Kivity]

On 10/21/2009 05:42 PM, Gregory Haskins wrote:
> I believe Avi, Michael, et. al. were in agreement with me on that design
> choice.  I believe the reason is that there is no good way to do EOI/ACK
> feedback within the constraints of an eventfd pipe which would be
> required for the legacy pin-type interrupts.  Therefore, we won't even
> bother trying.  High-performance subsystems will use irqfd/msi, and
> legacy emulation can use the existing injection code (which includes the
> necessary feedback for ack/eoi).
>
>    

Right.  But we don't actually prevent anyone using non-msi with irqfd, 
which can trigger the bad lock usage from irq context, with a nice boom 
afterwards.  So we need to either prevent it during registration, or to 
gracefully handle it afterwards.

--
error compiling committee.c: too many arguments to function

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