From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Pfeuffer <thomas.pfeuffer@mytum.de>
Subject: Question on pci-passthrough and event delivery
Date: Thu, 08 Apr 2010 10:48:03 +0200
Message-ID: <4BBD9843.60903@mytum.de>
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Hello,

I am using pci-passthrough mechanism in Xen 3.4.2-rc2 to passthrough the 
only Network Interface Card to a pv driver domain.

I have observed in xentrace output, that everytime a network packet 
arrives, the Xen hypervisor delivers an event to the driver domain and 
to dom0. I would think, that it is not neccassary to inform dom0, since 
only the driver domain has access to the NIC.

Why is the interrupt from the NIC delivered to dom0 via an event, too? 
Is it neccassary for pciback in dom0?

regards,

Thomas