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Date: Thu, 1 Oct 2015 07:57:31 -0700
From: Stephen Hemminger <stephen@networkplumber.org>
To: Avi Kivity <avi@scylladb.com>
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Cc: dev@dpdk.org, hjk@hansjkoch.de, gregkh@linux-foundation.org,
 linux-kernel@vger.kernel.org
Subject: Re: [dpdk-dev] [PATCH 0/2] uio_msi: device driver
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On Thu, 1 Oct 2015 13:59:02 +0300
Avi Kivity <avi@scylladb.com> wrote:

> On 10/01/2015 01:28 AM, Stephen Hemminger wrote:
> > This is a new UIO device driver to allow supporting MSI-X and MSI devices
> > in userspace.  It has been used in environments like VMware and older versions
> > of QEMU/KVM where no IOMMU support is available.  
> 
> Why not add msi/msix support to uio_pci_generic?

That is possible but that would meet ABI and other resistance from the author.
Also, uio_pci_generic makes it harder to find resources since it doesn't fully
utilize UIO infrastructure.