From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: FreeBSD guest with VTD NIC not passing traffic Date: Fri, 13 Jan 2012 22:00:21 +0100 Message-ID: <4F109B65.8020702@web.de> References: <1325647262.4305.47.camel@bling.home> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig895F84B663F3DB2A100438A7" Cc: Shashidhar Patil , kvm@vger.kernel.org To: Alex Williamson Return-path: Received: from fmmailgate02.web.de ([217.72.192.227]:47409 "EHLO fmmailgate02.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753739Ab2AMVA3 (ORCPT ); Fri, 13 Jan 2012 16:00:29 -0500 Received: from moweb002.kundenserver.de (moweb002.kundenserver.de [172.19.20.108]) by fmmailgate02.web.de (Postfix) with ESMTP id B56F01BF9FACA for ; Fri, 13 Jan 2012 22:00:22 +0100 (CET) In-Reply-To: <1325647262.4305.47.camel@bling.home> Sender: kvm-owner@vger.kernel.org List-ID: This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig895F84B663F3DB2A100438A7 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 2012-01-04 04:21, Alex Williamson wrote: > On Mon, 2011-12-19 at 19:49 +0530, Shashidhar Patil wrote: >> Hi, >> I am running Ubuntu 10.10 (amd64) on a 2 socket nehalem based >> server with IOH 5520. 5520 supports VTD. >> I enabled DMAR with intel_iommu=3Don. The box has intel 82599 adapter >> which I assigned through VT-D to FreeBSD 8.2 running >> as guest os. The ixgbe driver detects the device and the driver >> successfully configures the device. But the link >> never comes up. It looks like link up/down interrupts are not >> delivered. Then I checked kvm interrupt assignment and as expected >> kvm could not make MSI-X entries for the VT-d guest. So no output from= >> "grep kvm /proc/interrupt". By enabling some debugs in the >> qemu-kvm I figured out that the MSI-x updates are not received >> properly. It does look like Linux updates MSI-X table in a batch >> fashion >> which qemu-kvm gets in one shot and every thing works fine in case of= >> linux. In case of FreeBSD PCIE updates come /MSI-X entry >> which qemu-kvm can't make use. >=20 > That's right, Linux and Windows both seem to setup the MSI-X table then= > enable it in one shot, so we only trigger the interrupt programming whe= n > the enable bit is set. We don't trigger changes on writes to the MSI-X= > table... not very accurate emulation of mask bits. According to the PCI spec, updates that happen while a vector is unmasked, need not be considered by the hardware (thus the hypervisor here). Is that the scenario here? Jan --------------enig895F84B663F3DB2A100438A7 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.16 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk8Qm2UACgkQitSsb3rl5xTM6gCfbb1y71fdKGx/T2ejh4Ub8yKL G8UAoKS2oy3cSVnRctGsJLvTweHBZpGB =zZhO -----END PGP SIGNATURE----- --------------enig895F84B663F3DB2A100438A7--