From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45962) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z4Uee-0000y4-T1 for qemu-devel@nongnu.org; Mon, 15 Jun 2015 09:42:28 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z4Uea-0007oL-B7 for qemu-devel@nongnu.org; Mon, 15 Jun 2015 09:42:24 -0400 Received: from mail-wi0-f171.google.com ([209.85.212.171]:34451) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z4Uea-0007oA-5k for qemu-devel@nongnu.org; Mon, 15 Jun 2015 09:42:20 -0400 Received: by wicnd19 with SMTP id nd19so25177642wic.1 for ; Mon, 15 Jun 2015 06:42:19 -0700 (PDT) Message-ID: <557ED62A.8050409@linaro.org> Date: Mon, 15 Jun 2015 15:42:02 +0200 From: Eric Auger MIME-Version: 1.0 References: In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] Assigning an eth port to a guest VM List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Yehuda Yitschak , "qemu-devel@nongnu.org" Cc: Shadi Ammouri , Yuval Caduri Hi Yehuda, On 06/15/2015 01:01 PM, Yehuda Yitschak wrote: > Cc: Eric Auger > >> -----Original Message----- >> From: Yehuda Yitschak >> Sent: Monday, June 15, 2015 9:35 >> To: qemu-devel@nongnu.org >> Cc: Yuval Caduri; Shadi Ammouri >> Subject: Assigning an eth port to a guest VM >> >> Hello >> >> I would to ask your advice on how to assign a semi-virtualized Ethernet port >> to a guest VM >> >> The eth port's HW partially supports virtualization since the data path MMIO >> registers (which controls rx/tx operation) are duplicated per VM. >> So for the run-time operation the guest can directly access the MMIO >> registers, using VFIO-PLATFORM, and enjoy the performance benefit. >> >> However for the initial setup and occasional configuration the guest need to >> access control path registers which are shared for all guests. >> AFAIK this is usually done with HW emulation using trap & emulate with >> QEMU. >> So, to the best of my knowledge I need a mix of VFIO and HW emulation to >> get the port to work with device assignment , right ? Yes to me you're correct. >> >> Are there any standard methods for achieving this ? >> Is there an example for such an existing HW in QEMU ? Not yet unfortunately. To my knowledge the only platform devices that were assigned with QEMU VFIO platform were standalone duplicated devices, PL330, Calxeda Xgmac, SATA. So you are a trailblazer on that track. Best Regards Eric >> >> Thanks >> >> Yehuda Yitschak