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 12:15:18 +0300
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To: Avi Kivity <avi@scylladb.com>
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On Thu, Oct 01, 2015 at 11:52:26AM +0300, Avi Kivity wrote:
> I still don't understand your objection to the patch:
>=20
>=20
>     MSI messages are memory writes so any generic device capable
>     of MSI is capable of corrupting kernel memory.
>     This means that a bug in userspace will lead to kernel memory corru=
ption
>     and crashes.  This is something distributions can't support.
>=20
>=20
> If a distribution feels it can't support this configuration, it can dis=
able the
> uio_pci_generic driver, or refuse to support tainted kernels.=A0 If it =
feels it
> can (and many distributions are starting to support dpdk), then you're =
just
> denying it the ability to serve its users.

I don't, and can't deny users anything.  I merely think upstream should
avoid putting this driver in-tree.  By doing this, driver writers will
be pushed to develop solutions that can't crash kernel.

I pointed out one way to build it, there are sure to be more.

As far as I could see, without this kind of motivation, people do not
even want to try.

--=20
MST