From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Subject: Re: VFIO and scheduled SR-IOV cards
Date: Wed, 10 Jul 2013 13:23:55 +0300
Message-ID: <20130710102355.GB10203@redhat.com>
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To: =?iso-8859-1?Q?Beno=EEt?= Canet <benoit.canet-J9ArbTHlV+bR7s880joybQ@public.gmane.org>
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On Tue, Jun 04, 2013 at 05:50:30PM +0200, Beno=EEt Canet wrote:
> =

> Hello,
> =

> More informations on how the hardware works.
> =

> -Each VF will have its own memory and MMR, etc.
> That means the resources are not shared.
> =

> -Each VF will have its own bus number, function number and device number.
> That means request ID is separated for each VF.
> =

> There is also VF save/restore area for the switch.
> =

> A VF regular memory (not MMR) is still accessible after a switch out.
> =

> But when a function VF1 is scheduled a read to a MRR of VF number 0 could=
 return
> the value of the same MMR in VF number 1 because VF number 1 is switched =
on and
> the PF processor is busy servicing VF number 1.
> =

> This could confuse the guest VF driver so the unmap and block or a same g=
oal
> achieving technique is required.
> =

> I hope these informations makes the area of the problem to solve narrower.
> =

> Best regards
> =

> Beno=EEt Canet

Confused.
You have one VF accessing BAR of another VF?
Why?

-- =

MST