From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Wagner Subject: Re: Xen, IRQ-sharing and PCI passthrough Date: Wed, 8 Jul 2009 08:35:13 +0200 Message-ID: <20090708083513.774b8281@auedv3.syscomp.de> References: <20090707081952.5305d4c1@auedv3.syscomp.de> <4A53162C02000078000091BE@vpn.id2.novell.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1054372923==" Return-path: In-Reply-To: <4A53162C02000078000091BE@vpn.id2.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org --===============1054372923== Content-Type: multipart/signed; boundary="Sig_/eBmUn632x0LTCB0KnCopENt"; protocol="application/pgp-signature"; micalg=PGP-SHA1 --Sig_/eBmUn632x0LTCB0KnCopENt Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable > Assuming your kernel has a call to irq_ignore_unhandled() out of > note_interrupt(), [...] Judging from my backtrace this seems to be the case, right? > [...] there's nothing but using hardware's help (i.e. VT-d > interrupt remapping) to get this addressed: The pv passthrough > mechanism assumes that guests you assign physical devices to are well > behaved, and your guest isn't (it fails to disable the interrupt at > the device). Do I understand this correctly: For safe operation of a virtual machine using PCI passthrough and shared interrupts a well behaved operating system in the vm is necessary. That is an OS that shuts down the mapped devices correctly before turning off (unload kernel module). So what am I to to in the case that someone issues a "xm destroy" on such a vm? There is no way to cleanly shutdown in such a situation, is there? That's quite a risk for system stability of the host. One thoughtless "xm destroy" and the whole host is crashed, requiring at a minimum a cold reset or even a reinstall. Regards Florian -------------- Florian Wagner Abteilung EDV Telefon: 0821 / 4201 - 453 Fax: 0821 / 4201 - 411 E-Mail: f_wagner@syscomp.de Syscomp Biochemische Dienstleistungen GmbH August-Wessels-Stra=C3=9Fe 5, 86154 Augsburg Postfach 102506, 86015 Augsburg Telefon: 0821 / 4201 - 0 Fax: 0821 / 417992 Web: http://www.syscomp.de E-Mail: syscomp@syscomp.de Gesch=C3=A4ftsf=C3=BChrer: Dr. med. Bernd Schottdorf Gabriele Schottdorf Registergericht Augsburg HRB 8670 --Sig_/eBmUn632x0LTCB0KnCopENt Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEARECAAYFAkpUPiIACgkQujTGeTwhKysAigCgtILtNL+fntlWVPjSQ1VNQQ6A Qp0AoM3xpmWqZGXJgO2eUmdyWJH/3lVW =X62K -----END PGP SIGNATURE----- --Sig_/eBmUn632x0LTCB0KnCopENt-- --===============1054372923== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel --===============1054372923==--