Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761803AbZAUDFA (ORCPT ); Tue, 20 Jan 2009 22:05:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754191AbZAUDEv (ORCPT ); Tue, 20 Jan 2009 22:04:51 -0500 Received: from gateway-1237.mvista.com ([63.81.120.158]:28977 "EHLO gateway-1237.mvista.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754108AbZAUDEv (ORCPT ); Tue, 20 Jan 2009 22:04:51 -0500 Message-ID: <497690D1.1060405@ct.jp.nec.com> Date: Tue, 20 Jan 2009 19:04:49 -0800 From: Hiroshi Shimamoto User-Agent: Thunderbird 2.0.0.19 (Windows/20081209) MIME-Version: 1.0 To: Justin Madru Cc: "Justin P. Mattock" , Jesper Juhl , lkml , John Stoffel , Ingo Molnar , "H. Peter Anvin" Subject: Re: [bisected] 2.6.29-rc1 Firefox crashing on page load References: <4970F46F.4060803@gawab.com> <49714266.6020401@gawab.com> <49715039.2090406@gmail.com> <49719B53.8050300@gawab.com> <4972489B.30500@gawab.com> <497260FE.4010102@gmail.com> <4972723B.4000201@gawab.com> <49727BDE.9070509@gmail.com> <49751BA0.1040004@gawab.com> <49752823.9020403@ct.jp.nec.com> <49756D07.7080804@gawab.com> <497617D6.8020707@ct.jp.nec.com> <4976246D.1040008@gawab.com> <49762AA3.7050402@ct.jp.nec.com> <49768ACF.5010608@gawab.com> In-Reply-To: <49768ACF.5010608@gawab.com> 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 Content-Length: 4799 Lines: 132 Justin Madru wrote: > Hiroshi Shimamoto wrote: >> Justin Madru wrote: >> >>> Hiroshi Shimamoto wrote: >>> >>>> Justin Madru wrote: >>>> >>>> >>>>> Hiroshi Shimamoto wrote: >>>>> >>>>> >>>>>> Justin Madru wrote: >>>>>> >>>>>> >>>>>>> Ok, finally bisected the bug, but the commit isn't related to networking! >>>>>>> I did: git revert 4217458dafaa57d8e26a46f5d05ab8c53cf64191 >>>>>>> on current git and that fixed the bug. >>>>>>> >>>>>>> By the way, how do I undo my git revert, so I'm back to a pristine tree? >>>>>>> I want to drop my changes - the revert. >>>>>>> Also how do I find the commit that merged/pulled in this commit? >>>>>>> >>>>>>> commit 4217458dafaa57d8e26a46f5d05ab8c53cf64191 >>>>>>> Author: Hiroshi Shimamoto >>>>>>> Date: Fri Dec 5 17:17:09 2008 -0800 >>>>>>> >>>>>>> x86: signal: change type of paramter for sys_rt_sigreturn() >>>>>>> >>>>>>> Impact: cleanup on 32-bit >>>>>>> >>>>>>> Peter pointed this parameter can be changed. >>>>>>> >>>>>>> Signed-off-by: Hiroshi Shimamoto >>>>>>> Signed-off-by: Ingo Molnar >>>>>>> >>>>>>> >>>>>> Hi, >>>>>> thanks for reporting. >>>>>> >>>>>> I'm not sure why this commit affects. >>>>>> Can you check vmlinux? size, objdump, etc. >>>>>> On my environment, the generated code looks same. >>>>>> >>>>>> Thanks, >>>>>> Hiroshi >>>>>> >>>>>> >>>>>> >>>>> I tried to do an objdump but it gave an error. How am I suppose to do an >>>>> objdump? >>>>> >>>>> $ objdump -x /boot/vmlinuz-2.6.29-rc2-git >>>>> objdump: /boot/vmlinuz-2.6.29-rc2-git: File format not recognized >>>>> $ readelf -a /boot/vmlinuz-2.6.29-rc2-git >>>>> readelf: Error: Unable to seek to 0xc031f2eb for section headers >>>>> readelf: Error: Not an ELF file - it has the wrong magic bytes at the start >>>>> $ ls -la /boot/vmlinuz-2.6.29-rc2-git >>>>> -rw-r--r-- 1 root root 2286480 2009-01-19 18:44 /boot/vmlinuz-2.6.29-rc2-git >>>>> >>>>> >>>> not vmlinuz, vmlinux. >>>> vmlinuz is a compressed kernel, it is not ELF file. >>>> Usually vmlinux is generated in top of source directory. >>>> I can see disassembled image with objdump -d vmlinux. >>>> >>>> Thanks, >>>> Hiroshi >>>> >>>> >>>> >>> Sorry, didn't know. I tried objdump -d vmlinux, but the resulting file >>> is ~50MB! >>> Is there a smaller section you're interested in, because that would be >>> hard to send. >>> Or am I doing it wrong again? >>> >> that's OK. No need to send the disassembled result. >> You can diff disassembled file. >> I guess your GCC generates different code when the patch is reverted. >> >> Thanks, >> Hiroshi >> >> > Ok, I tried, I really did. But no mater what I did the diff was even bigger > if not the same size as the original dump! I even tried to cut out the > first two fields with > cut -f3- dump-revert > dump-revert2 > but that wouldn't shrink the diff size (100,000+ lines). I'm sorry for lack of explanations. The patch changes sys_rt_sigreturn(), it means GCC might generate different code for that function. And might be different size, it causes all codes after sys_rt_sigreturn() will looks different. So I think you can see the difference begins from sys_rt_sigreturn(). > > Does gcc output fluctuate this wildly with such little change? > Is there a config option that allows gcc to randomize the output? > I recompiled just to make sure, and even two recompiles of the same > source (no revert) > resulted in a different sha1 hash (didn't test the objdump diff). > The only thing I can think of is that I compile with -O3 instead of -O2. > > I'm sorry, but unless you have any suggestions I've decided to just upload > the vmlinux files to my server (<40KB up speed) > http://jdserver.homelinux.org/bugreports/002/ > and rapidshare > http://rapidshare.com/files/186890846/vmlinux.tar.bz2.html > http://rapidshare.com/files/186890848/data-norevert.tar.bz2.html > http://rapidshare.com/files/186890849/data-revert.tar.bz2.html thanks for uploading vmlinux, will see the difference. And sorry again, actually, it's just for my curiosity. I'd like to know what difference this is. On my environment GCC(4.2.4-1ubuntu3 and 4.3.2) generates same binary... > > By the way Ingo has already added the revert to tip/master > http://git.kernel.org/?p=linux/kernel/git/tip/linux-2.6-tip.git;a=commit;h=1d03950243904c89b8854c10516932b029c2a8fa Yeah, Ingo knows what GCC does. I don't know so much. Thanks, Hiroshi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/