From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: current qemu-kvm doesn't work with vhost Date: Sun, 19 Jun 2011 10:58:20 +0200 Message-ID: <4DFDBA2C.2090307@web.de> References: <1308342664.3033.1@sylvester> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig8C41261508CE768569869AD5" Cc: kvm@vger.kernel.org To: Georg Hopp Return-path: Received: from fmmailgate03.web.de ([217.72.192.234]:44714 "EHLO fmmailgate03.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752422Ab1FSI6W (ORCPT ); Sun, 19 Jun 2011 04:58:22 -0400 In-Reply-To: <1308342664.3033.1@sylvester> Sender: kvm-owner@vger.kernel.org List-ID: This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig8C41261508CE768569869AD5 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 2011-06-17 22:31, Georg Hopp wrote: > Am 17.06.2011 09:29:41 schrieb(en) Jan Kiszka: >> On 2011-06-17 09:10, Georg Hopp wrote: >> > Jan Kiszka web.de> writes: >> >> >> >> On 2011-06-10 05:08, Amos Kong wrote: >> >>> host kernel: 2.6.39-rc2+ >> >>> qemu-kvm : 05f1737582ab6c075476bde931c5eafbc62a9349 >> >>> >> >>> (gdb) r -monitor stdio -m 800 ~/RHEL-Server-6.0-64-virtio.qcow2 >> -snapshot >> > -device >> >> virtio-net-pci,netdev=3Dhe -netdev tap,vhost=3Don,id=3Dhe >> >>> >> >> >> >> I already came across that symptom in a different context. Fixed by= >> the >> >> patch below. >> >> >> >> However, the real issue is related to an upstream cleanup of the >> >> virtio-pci build. That reveals some unneeded build dependencies in >> >> qemu-kvm. Will post a fix. >> >> >> >> Jan >> > >> > FYI >> > >> > I encountered the same problem and applied the patch. >> > >> > Well this results in the following error while starting the guest: >> > >> > qemu-system-x86_64: unable to start vhost net: 38: >> > falling back on userspace virtio >> > >> > and i have no network at all. I will disable vhost=3Don for now. >> >> Hmm, works fine for me. The vhost-net module is loaded (though I got a= >> different message when I forgot to load it)? >> >> Jan >> >=20 > Generally it works for me until git revision b2146d8bd. You mean including that commit, right? >=20 > I have compiled vhost-net directly in my kernel so a have definetly not= > forgotten to load it... > As i use gentoo i made an ebuild that installes exactly this revision. > If i find the time to do some debugging i will do so, but actually i am= > very busy with my job > family and the use of kvm is just a sparetime thing. :D >=20 > If it would be of some help i can set a breakpoint just before the path= > and see what > causes the message. Let's start with double-checking that you are on ce5f0a588b, did a make clean && make, and then actually used that result. I suspect an inconsistent build as ce5f0a588b makes the difference between ENOSYS (38) and working vhost support here. Jan --------------enig8C41261508CE768569869AD5 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.15 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org/ iEYEARECAAYFAk39uiwACgkQitSsb3rl5xSEmwCgqRpuAZ0pY6WDvnqKR3oaxmvr y3YAn3RSs31TwsdlQ9rjDeVhU8JGJ2Rh =ej2L -----END PGP SIGNATURE----- --------------enig8C41261508CE768569869AD5--