From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: Having troubles binding an SR-IOV VF to
 uio_pci_generic on Amazon instance
Date: Thu, 1 Oct 2015 12:42:04 +0300
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To: Avi Kivity <avi@scylladb.com>
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On Thu, Oct 01, 2015 at 12:22:46PM +0300, Avi Kivity wrote:
> even when they are some users
> prefer to avoid the performance penalty.

I don't think there's a measureable penalty from passing through the
IOMMU, as long as mappings are mostly static (i.e. iommu=pt).  I sure
never saw any numbers that show such.

-- 
MST