From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752317Ab1AHWqm (ORCPT ); Sat, 8 Jan 2011 17:46:42 -0500 Received: from cantor.suse.de ([195.135.220.2]:36832 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752181Ab1AHWql (ORCPT ); Sat, 8 Jan 2011 17:46:41 -0500 Message-ID: <4D28E945.3060504@suse.com> Date: Sat, 08 Jan 2011 17:46:29 -0500 From: Jeff Mahoney User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101206 SUSE/3.1.7 Thunderbird/3.1.7 MIME-Version: 1.0 To: Florian Mickler Cc: Dan Carpenter , Andrew Morton , "David S. Miller" , balbir@linux.vnet.ibm.com, Linux Kernel Mailing List Subject: Re: [PATCH] taskstats: Use better ifdef for alignment References: <4D1BCE58.4000902@suse.com> <20101229161418.d34bf0d4.akpm@linux-foundation.org> <4D1C180A.20000@suse.com> <20101229213243.891b0db5.akpm@linux-foundation.org> <4D1CAAA1.8030106@suse.com> <20110101171946.6179c3b6@schatten.dmk.lab> <20110101165135.GJ1886@bicker> <20110102131747.3e79107a@schatten.dmk.lab> In-Reply-To: <20110102131747.3e79107a@schatten.dmk.lab> X-Enigmail-Version: 1.1.2 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 01/02/2011 07:17 AM, Florian Mickler wrote: > On Sat, 1 Jan 2011 19:51:35 +0300 > Dan Carpenter wrote: > >> On Sat, Jan 01, 2011 at 05:19:46PM +0100, Florian Mickler wrote: >>> Is there already a patch available or integrated into iotop which >>> fixes this? I'd think that if the kernel could wait on fixed iotop's to >>> be distributed it would be easier to sell the breakage on bugzilla & >>> co... >>> >> >> The story is that 4be2c95d1f "taskstats: pad taskstats netlink response >> for aligment issues on ia64" broke iotop on 64 bit processors (32 bit >> was unaffected). This patch fixes it for x86-64 and powerpc-64. >> >> On the other 64 bit processors iotop works but instead you get a message >> in dmesg: >> kernel unaligned access to 0xe000023879dca9bc, ip=0xa000000100133d10 >> >> So on those arches you were already getting posts to bugzilla etc. Now >> those people can upgrade the kernel and download iotop version 0.4.2 or >> higher. >> >> regards, >> dan carpenter >> > > Ah ok. And probably bug #24272 is related to this. If I > understood it correctly 85893120 fixed some runtime warnings (or more > exactly the misaligning) and broke iotop in the process (on all of 64 > bit). > > 4be2c95d1f undid that and enhanced the netlink messages on IA64 > archs with a new type to fix the alignment and now it's changed to > align well on all archs that need alignment, leaving archs unbroken that > have efficient unaligned access (x86-64 and powerpc-64). Nice. > > And to answer my original question, i just checked out (some?/the?) > iotop sources from git://repo.or.cz/iotop.git and found a fix[1] for the > issue with 85893120. > > Is iotop parsing fixed to ignore the null-field in the meantime? It isn't yet, but I sent Guillaume a patch to iotop when I sent in the null-field patch that actually parses the packet instead of doing field-offset tricks. - -Jeff > Thx, > Flo > > [1]git://repo.or.cz/iotop.git:commit 08211d209ae8fc7e67ea3bebb09979ff61c70f97 > Author: Guillaume Chazarain > Date: Sat Sep 4 13:57:43 2010 +0200 > > Instead of assuming the pid field is 4 bytes long, take its length from the header. > This is needed for http://lkml.org/lkml/2010/2/12/167 > [PATCH] delayacct: align to 8 byte boundary on 64-bit systems - -- Jeff Mahoney SUSE Labs -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.16 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org/ iEYEARECAAYFAk0o6UUACgkQLPWxlyuTD7Is/wCfTUBE/2hg19vfGO2Wzk3Zkguo mW8AnAv6ey78E7dJsvkKLy/YS6vW10cE =fUIp -----END PGP SIGNATURE-----