From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Savchenko Subject: Re: [BUG] Kernel recieves DNS reply, but doesn't deliver it to a waiting application Date: Wed, 12 Dec 2012 12:27:16 +0400 Message-ID: <20121212122716.1e71f644.bircoph@gmail.com> References: <20121003232548.eb6b6b22.bircoph@gmail.com> <20121013163639.87abca00.bircoph@gmail.com> <1350135860.21172.14606.camel@edumazet-glaptop> <20121014031119.a60263d6.bircoph@gmail.com> <20121021032543.09d1844f.bircoph@gmail.com> <1350823941.13333.2167.camel@edumazet-glaptop> <20121022073636.98462bc6.bircoph@gmail.com> <1350888489.8609.322.camel@edumazet-glaptop> <20121023012759.ca7f91d6.bircoph@gmail.com> Mime-Version: 1.0 Content-Type: multipart/signed; protocol="application/pgp-signature"; micalg="PGP-SHA1"; boundary="Signature=_Wed__12_Dec_2012_12_27_16_+0400_GLqUUcNHCf1h4znH" Cc: netdev@vger.kernel.org To: Eric Dumazet Return-path: Received: from mail-lb0-f174.google.com ([209.85.217.174]:51704 "EHLO mail-lb0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751025Ab2LLI1c (ORCPT ); Wed, 12 Dec 2012 03:27:32 -0500 Received: by mail-lb0-f174.google.com with SMTP id gi11so346707lbb.19 for ; Wed, 12 Dec 2012 00:27:30 -0800 (PST) In-Reply-To: <20121023012759.ca7f91d6.bircoph@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: --Signature=_Wed__12_Dec_2012_12_27_16_+0400_GLqUUcNHCf1h4znH Content-Type: text/plain; charset=US-ASCII Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hello, On Tue, 23 Oct 2012 01:27:59 +0400 Andrew Savchenko wrote: > On Mon, 22 Oct 2012 08:48:09 +0200 Eric Dumazet wrote: [...] > > Some driver or protocol stack is messing with skb->truesize, as > > your /proc/net/udp file contains anomalies : > >=20 > > $ cat /proc/net/udp > > sl local_address rem_address st tx_queue rx_queue tr tm->when retr= nsmt uid timeout inode ref pointer drops > > ... > > 323: 074A070A:007B 00000000:0000 07 FFFDF700:00000000 00:00000000 000= 00000 123 0 254469 2 ffff88003d581880 0 > > ... > > 323: 00FCA8C0:007B 00000000:0000 07 FFFFF900:00000000 00:00000000 000= 00000 0 0 5187 2 ffff880039993880 0 > >=20 > > Its clearly not possible to get tx_queue =3D 0xFFFDF700 or 0xFFFFF900 > >=20 > > So what drivers handle following IP addresses : 192.168.252.0 , 10.7.74= .7 ? >=20 > 192.168.252.0 is handled by eth0 interface running on Realtek > Semiconductor Co., Ltd. RTL-8139/8139C/8139C+ (10ec:8139) NIC. > Kernel driver 8139too. This interface handles multiple subnetworks: >=20 > # ip addr show eth0 > 2: eth0: mtu 1500 qdisc pfifo_fast stat= e UNKNOWN qlen 1000=20 > link/ether 00:80:48:30:ca:f3 brd ff:ff:ff:ff:ff:ff > inet 10.51.15.126/25 brd 10.51.15.127 scope global eth0 > inet 192.168.252.0/31 scope global eth0 >=20 > 10.7.74.7 is an l2tp connection handled by ppp over l2tp: > CONFIG_PPPOL2TP=3Dy > It is running on top of eth0 described above. >=20 > # ip addr show ppp0 > 65: ppp0: mtu 1400 qdisc pfifo_= fast state UNKNOWN qlen 3 > link/ppp=20 > inet 10.7.74.7 peer 10.7.2.18/32 scope global ppp0 I updated kernel on this system to 3.7.0 and udp anomaly is still present: $ cat /proc/net/udp sl local_address rem_address st tx_queue rx_queue tr tm->when retrnsmt= uid timeout inode ref pointer drops =20 0: 00000000:06A5 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5326 2 ffff88003dbf0a80 0 =20 8: 00000000:7EAD 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5157 2 ffff8800398c2000 0 =20 89: 00000000:90FE 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5101 2 ffff88003dbd3500 0 =20 160: 0100007F:2745 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 4598 2 ffff88003d612700 0 =20 184: 0100007F:035D 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 4774 2 ffff88003d612a80 0 =20 217: 00000000:857E 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5195 2 ffff8800398c2700 0 =20 318: 00000000:A9E3 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 4782 2 ffff88003d612e00 0 =20 335: 7E0F330A:01F4 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5303 2 ffff8800398c2e00 0 =20 348: 00000000:0801 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5186 2 ffff8800398c2380 0 =20 387: 7E0F330A:DE28 1400320A:06A5 01 00000000:00000000 00:00000000 0000000= 0 0 0 5332 4 ffff88003dbf0e00 0 =20 400: 010013AC:0035 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 4842 2 ffff88003d613880 0 =20 400: 0100007F:0035 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 4841 2 ffff88003d613500 0 =20 414: 00000000:0043 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5273 2 ffff8800398c2a80 0 =20 458: 00000000:006F 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 4483 2 ffff88003d612000 0 =20 459: 00000000:0270 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 4507 2 ffff88003d612380 0 =20 466: 00000000:0277 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 4802 2 ffff88003d613180 0 =20 470: 076A070A:007B 00000000:0000 07 FFFF4600:00000000 00:00000000 0000000= 0 123 0 5552 2 ffff880039974380 0 =20 470: 010213AC:007B 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 4986 2 ffff88003dbd3180 0 =20 470: 010013AC:007B 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 4985 2 ffff88003dbd2e00 0 =20 470: 00FCA8C0:007B 00000000:0000 07 FFFFFB00:00000000 00:00000000 0000000= 0 0 0 4984 2 ffff88003dbd2a80 0 =20 470: 7E0F330A:007B 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 4983 2 ffff88003dbd2700 0 =20 470: 0100007F:007B 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 4982 2 ffff88003dbd2380 0 =20 470: 00000000:007B 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 4975 2 ffff88003d613c00 0 =20 484: FF0013AC:0089 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5316 2 ffff88003dbf0000 0 =20 484: 010013AC:0089 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5315 2 ffff88003dbd3880 0 =20 484: FF0213AC:0089 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5312 2 ffff8800398c3c00 0 =20 484: 010213AC:0089 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5311 2 ffff8800398c3880 0 =20 484: 00000000:0089 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5308 2 ffff8800398c3180 0 =20 485: FF0013AC:008A 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5318 2 ffff88003dbf0700 0 =20 485: 010013AC:008A 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5317 2 ffff88003dbf0380 0 =20 485: FF0213AC:008A 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5314 2 ffff88003dbd3c00 0 =20 485: 010213AC:008A 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5313 2 ffff88003dbd2000 0 =20 485: 00000000:008A 00000000:0000 07 00000000:00000000 00:00000000 0000000= 0 0 0 5309 2 ffff8800398c3500 0 The bug hasn't shown up yet, I'll need to wait for about a week to see if it is reproducible. Best regards, Andrew Savchenko --Signature=_Wed__12_Dec_2012_12_27_16_+0400_GLqUUcNHCf1h4znH Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (GNU/Linux) iEYEARECAAYFAlDIP+8ACgkQ2anJBBcsZw2c5gCfa0YkkXaV6eCilQ9bMOaBck6d lvQAoMXN9E1HlR5wbPCwlRbBXtbrqt/r =z/oJ -----END PGP SIGNATURE----- --Signature=_Wed__12_Dec_2012_12_27_16_+0400_GLqUUcNHCf1h4znH--