From mboxrd@z Thu Jan 1 00:00:00 1970 From: Doug Ledford Subject: Re: 4.4-rc7 failure report Date: Wed, 30 Dec 2015 13:47:51 -0500 Message-ID: <568426D7.9000108@redhat.com> References: <5683A630.2070401@iogearbox.net> <20151230151123.GB4874@codemonkey.org.uk> <1451494525.8255.21.camel@edumazet-glaptop2.roam.corp.google.com> <20151230.125003.301825767708169401.davem@davemloft.net> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="LHKwKvoMDB0pKDA54I1HTjF4q6RDsDNJo" Cc: davej@codemonkey.org.uk, daniel@iogearbox.net, alexei.starovoitov@gmail.com, netdev@vger.kernel.org To: David Miller , eric.dumazet@gmail.com Return-path: Received: from mx1.redhat.com ([209.132.183.28]:36082 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751157AbbL3SsB (ORCPT ); Wed, 30 Dec 2015 13:48:01 -0500 In-Reply-To: <20151230.125003.301825767708169401.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-ID: This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --LHKwKvoMDB0pKDA54I1HTjF4q6RDsDNJo Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable On 12/30/2015 12:50 PM, David Miller wrote: > From: Eric Dumazet > Date: Wed, 30 Dec 2015 11:55:25 -0500 >=20 >> On Wed, 2015-12-30 at 10:11 -0500, Dave Jones wrote: >>> On Wed, Dec 30, 2015 at 10:38:56AM +0100, Daniel Borkmann wrote: >>> >>> > Given that this drop doesn't strictly need to be caused by filter = code, >>> > it would be nice if you could pin the location down where the pack= et gets >>> > dropped exactly. Perhaps dropwatch or perf with '-e skb:kfree_skb = -a -g >>> > dhclient ', etc could help to get a first overview to dig i= nto >>> > details then. >>> >>> Wild stab in the dark, but.. >>> Could this bug be another symptom fixed by http://article.gmane.org/g= mane.linux.network/392885 ? >> >> dhclient does not use async io >=20 > But the bug causes requests to "LOOK" like async I/O, right? >=20 I got my hands on a machine that's reliable, so the bisecting is finally progressing again. The machines with ocrdma devices can have link issues, the machines with mlx5 devices don't support vlans in all kernel versions, and some of my machines with mlx4 devices simply didn't have their Ethernet port plugged in. I managed to check out a machine with mlx4 in IB/Eth mode that is otherwise reliable on all of the kernel versions the bisection covers and modified its setup to show me at a glance if the dhcp on vlan is working and now I'm probably over half down with the bisection. --=20 Doug Ledford GPG KeyID: 0E572FDD --LHKwKvoMDB0pKDA54I1HTjF4q6RDsDNJo 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 Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQIcBAEBCAAGBQJWhCbXAAoJELgmozMOVy/dvQ4P/A6KBM1vhKvzhaqwAm6r4Hmw EzMw1sv5jgHdGQ+/Pn3+G8qJJDB+2U2U/QnoIZfWUzAhCiJJezRO09OJqzxlEnrb z2WXpHMinGIRdeqwRFoS87rNggh7XtFewwhtdS0EXL/YyugI+rqq/wsxOVKCaML6 J+MKCqk4FbiTM6IlKyvvshp/6C940ai8Zl5EwZma4FC8LnHcgfBzR+XbYbp+0urQ W4olFH2dkvE92qL7+cbincVZVECcuxatV+72UDhiD+ORHw3urrPqa3nWK7U2B4fc zrxUxTWatIqiRLteRDczqIw4f7SYh+Gd1KQEL2uH58vwpopvbk5xyIBvWkSlW7WD UeS1yF75LwBNHz1+VvGgd21m2KgegiAL6i3X+eqfpGf0tE8ZeywzfZghdAy8n7R7 KYDjlCABuYCOiuJE2NHoj0K7MVu+AZErNrBSVFy6BlUoAD87HMYsIoGqHyc2pWbK oxPMzHMMRJVVsME7hvFgPg3L75oXO5oMx5qHP55daCwWkpuRN3wHpuwgPcyzAKIm 9gMIsqut0ltSgCMS1MFfasWyyo/3vQe+VNkjSZjpWG8zGYj/aN8J+YW7IN6FqN1b eGHAImsV56ZofB7x/qGj2pXmqkRbccg9BYRiE1+viiPkySaxit2GStEonkGcH3f7 PIW+yrIRBdQxIzAG47+P =4DQl -----END PGP SIGNATURE----- --LHKwKvoMDB0pKDA54I1HTjF4q6RDsDNJo--