From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH] KVM: Allow host IRQ sharing for assigned PCI 2.3 devices
Date: Wed, 11 Jan 2012 11:47:13 +0200
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Cc: Jan Kiszka <jan.kiszka@siemens.com>, Avi Kivity <avi@redhat.com>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	kvm <kvm@vger.kernel.org>,
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To: Alex Williamson <alex.williamson@redhat.com>
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On Tue, Jan 10, 2012 at 04:41:50PM -0700, Alex Williamson wrote:
> > The guest driver will never see such an interrupt as we will notice on
> > its arrival that there is some mask pending.
> 
> Right, I was thinking more about the affect at the hardware level.

In theory a broken device might assume that intx disable
bit is correlated with internal device registers somehow.
However, the current sharing approach won't work for such
a device anyway as host controls the status bit while
guest controls the rest of the device. So I think we don't care.

-- 
MST