From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Bader Subject: Re: [Xen-devel] compound skb frag pages appearing in start_xmit Date: Tue, 20 Nov 2012 09:30:21 +0100 Message-ID: <50AB3F9D.4070905@canonical.com> References: <1349790467.21847.185.camel@zakaz.uk.xensource.com> <1349790863.21172.4406.camel@edumazet-glaptop> <1349792241.21847.199.camel@zakaz.uk.xensource.com> <1349792847.21172.4479.camel@edumazet-glaptop> <1349793630.21847.208.camel@zakaz.uk.xensource.com> <1349863984.10070.26.camel@zakaz.uk.xensource.com> <1349874598.10070.39.camel@zakaz.uk.xensource.com> <748966751.20121010164949@eikelenboom.it> <1349942546.14806.7.camel@zakaz.uk.xensource.com> <151954917.20121011120004@eikelenboom.it> <1349949924.21172.8462.camel@edumazet-glaptop> <1349950494.14806.29.camel@zakaz.uk.xensource.com> <50A4540E.1010601@oracle.com> <1333495676.20121119164304@eikelenboom.it> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="------------enig9491B69895AA4970D7941DA3" Cc: ANNIE LI , Ian Campbell , Eric Dumazet , "netdev@vger.kernel.org" , "Marcos E. Matsunaga" , xen-devel , Konrad Rzeszutek Wilk , Eric Dumazet To: Sander Eikelenboom Return-path: Received: from youngberry.canonical.com ([91.189.89.112]:49405 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752809Ab2KTIag (ORCPT ); Tue, 20 Nov 2012 03:30:36 -0500 In-Reply-To: <1333495676.20121119164304@eikelenboom.it> Sender: netdev-owner@vger.kernel.org List-ID: This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig9491B69895AA4970D7941DA3 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 19.11.2012 16:43, Sander Eikelenboom wrote: >=20 > Thursday, November 15, 2012, 3:31:42 AM, you wrote: >=20 >> On 2012-10-11 18:14, Ian Campbell wrote: >>> On Thu, 2012-10-11 at 11:05 +0100, Eric Dumazet wrote: >>>> On Thu, 2012-10-11 at 12:00 +0200, Sander Eikelenboom wrote: >>>> >>>>> Probably due to the BUG_ON from the patch below, i changed it into = a WARN_ON. >>>>> And i seem to hit it, but only in one of the guests at the moment a= nd it triggers quite irregularly. >>>> xennet_make_frags() is able to split the skb->head in multiple page-= size >>>> chunks. >>>> >>>> It should do the same for fragments >>> Right, I just want to be reproduce the issue so I can know I've fixed= it >>> properly ;-) >> Hi Ian, >=20 >> I can reproduce this BUG_ON when running netperf/netserver test betwee= n=20 >> two domus running on the same dom0. The domu and dom0 all use v3.7-rc1= =2E >=20 >> When I tried to rebase my persistent grant netfront/netback patch on=20 >> latest kernel, netperf/netserver test never succeeded. I did some test= =20 >> to find out that v3.6-rc7 works fine, but v3.7-rc1, v3.7-rc2 and=20 >> v3.7-rc4 does not succeed in netperf/netserver test. So I keep my=20 >> persistent grant patch only based on v3.4-rc3 now. >=20 >> Konrad thought about commit 6a8ed462f16b8455eec5ae00eb6014159a6721f0 i= n=20 >> v3.7-rc1, and suggested me to test your debug patch in netfront. This = >> BUG_ON happens soon after running the netperf/netserver test case. >=20 >> Thanks >> Annie >=20 > Is there any progression with this bug (rc6 is out the door, so the rel= ease of 3.7-final seems to be eminent and this bug completely cripples an= y networking with guests) ? >=20 +1 on that. I was testing yesterday with a PVM domU running 3.7-rc5 on Xe= n 4.2 (but also reported from EC2 running Xen 3.4.3) c with one VCPU. I actuall= y can trigger it by just ssh'ing into the domU (from another machine) and then = run "find /". Output starts to stutter and then stops completely. When this h= appens a new connection still can be made and as long as only shorter output is generated the ssh connection is ok. From a dump taken it looks like user-= space is waiting in some select call (without any warnon I rather won't see the= tx path). -Stefan --------------enig9491B69895AA4970D7941DA3 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://www.enigmail.net/ iQIcBAEBCgAGBQJQqz+kAAoJEOhnXe7L7s6juzcP/jOI3Ac4Nix8czBGsHJE9Rl5 R7icGSpb8Dpr8tWeWd3l5U0EYzcyARcfy6SKHYHcMEQth35nWsHdR55koB7ATzZZ bZyooTSRGqsepuw9DWilgjvfR27zDFdymi/GIDaMVCIUxIvW0F+IVB++mstMUXZv PTemlzKQtvflgIuDhia26sd6PfV/9AhmU757gzpMwuciStKuPgkBWEr6STnFQzEe dCDCYCpFKYGcGRvnEsQT8p8ArLR9FEju/PmO1YjkSRiohTPGB1JFMSWTk83QIFj0 lU7c2FZr6DB7gC3ITTUERfw6kyPgkjIbK5qAVLUtJEjuqOueI9HZQ8qEuo9i4rdt jRycw6Ff22qUCyKTvwcM9JK55GnFHmkUkC8n7hU4PRM2VuOS4+3K2o/Dia0vxgB0 JOvhRQFH2NfmJgeVIkbXpInu2WuRhFGtTEHA4HWF2MoBLaJYktKoqq8GS80+gLe2 pn31LUaj4NO/Ofb+7njY+dBiZLil4y3m02Qa0dVnuOcC58J5LaVAIYUhMhfGODCA unB71Y0OP3pHahK7shd5sVmTZ72f6hL4paBEi6zFz0JvBdrAGDGth7uzzfXDxG30 cEyQUG0B7NexC3/WZhq1FDq1UsVcJHCly8Lp5CPkXPOdbchCqh3DukHlD12ozv2z atR22nwyftzXhcTVvXE7 =zNki -----END PGP SIGNATURE----- --------------enig9491B69895AA4970D7941DA3--