Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4D966C433F5 for ; Wed, 15 Dec 2021 05:22:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239876AbhLOFW1 (ORCPT ); Wed, 15 Dec 2021 00:22:27 -0500 Received: from mga09.intel.com ([134.134.136.24]:60572 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239861AbhLOFW0 (ORCPT ); Wed, 15 Dec 2021 00:22:26 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1639545746; x=1671081746; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=Ut1Q/Z+F1qkXD5SI3hngsNT+FiBiMeYWIbrufPg5mKI=; b=VNQ2eromDdWcoioC06wrqVBWDadyzZIJqFjsjHALBhMhyIc76TlDC2oT rNjqhiV6fnX9uHKLBUgZhBTH3KZ5SXED3kcJCYH7jpQh5hJ0CBYbxOXiO Yyw2tG9KaiJ5bxQP/G9HcisL10aaP2hQB2UlTvhd/nQWQk1xg+s++xr6F Rqbjyb3PhWw+bThM6X4cmuG7ic0xU16dflxpLXnX6il03OSyrSGR8g8u8 1X1g8q3eKi/BIoJ5myCHDg8Xhi4LVPq/9+CWTPaa6G1+DZFGkVbZhxlcN vcgkH1FXgEE9Uryp9BfNA/bfEIMbSAXxsq6dDc28cLsxsbCE1tlre1HMm Q==; X-IronPort-AV: E=McAfee;i="6200,9189,10198"; a="238964380" X-IronPort-AV: E=Sophos;i="5.88,207,1635231600"; d="scan'208";a="238964380" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Dec 2021 21:22:25 -0800 X-IronPort-AV: E=Sophos;i="5.88,207,1635231600"; d="scan'208";a="518608275" Received: from rongch2-desk.sh.intel.com (HELO [10.239.159.175]) ([10.239.159.175]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Dec 2021 21:22:24 -0800 Message-ID: Date: Wed, 15 Dec 2021 13:22:21 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.3.1 Subject: Re: [kbuild-all] Re: [ebiederm-user-namespace:signal-for-v5.17 4/12] arch/x86/kernel/dumpstack.o: warning: objtool: oops_end() falls through to next function show_opcodes() Content-Language: en-US To: "Eric W. Biederman" Cc: kernel test robot , kbuild-all@lists.01.org, linux-kernel@vger.kernel.org References: <202112140949.Uq5sFKR1-lkp@intel.com> <87k0g7t7ry.fsf@email.froward.int.ebiederm.org> <2af5f2f0-b2db-35e3-2d7a-7fa512db19af@intel.com> <8735mutqvz.fsf@email.froward.int.ebiederm.org> From: Rong Chen In-Reply-To: <8735mutqvz.fsf@email.froward.int.ebiederm.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/15/21 12:48, Eric W. Biederman wrote: > Rong Chen writes: > >> On 12/15/21 01:29, Eric W. Biederman wrote: >>> kernel test robot writes: >>> >>>> tree: https://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git signal-for-v5.17 >>>> head: 6b1248798eb6f6d5285db214299996ecc5dc1e6b >>>> commit: 0e25498f8cd43c1b5aa327f373dd094e9a006da7 [4/12] exit: Add and use make_task_dead. >>>> config: x86_64-randconfig-a011-20211213 (https://download.01.org/0day-ci/archive/20211214/202112140949.Uq5sFKR1-lkp@intel.com/config) >>>> compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 >>>> reproduce (this is a W=1 build): >>>> # https://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git/commit/?id=0e25498f8cd43c1b5aa327f373dd094e9a006da7 >>>> git remote add ebiederm-user-namespace https://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git >>>> git fetch --no-tags ebiederm-user-namespace signal-for-v5.17 >>>> git checkout 0e25498f8cd43c1b5aa327f373dd094e9a006da7 >>>> # save the config file to linux build tree >>>> mkdir build_dir >>>> make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash arch/x86/kernel/ kernel/ lib/kunit/ >>>> >>>> If you fix the issue, kindly add following tag as appropriate >>>> Reported-by: kernel test robot >>>> >>>> All warnings (new ones prefixed by >>): >>>> >>>>>> lib/kunit/kunit-example-test.o: warning: objtool: .text.unlikely: unexpected end of section >>>> -- >>>>>> arch/x86/kernel/dumpstack.o: warning: objtool: oops_end() falls through to next function show_opcodes() >>> I am confused. This change patches objtool to rename >>> rewind_stack_and_do_exit to rewind_stack_and_make_dead in the list >>> global_noreturns in tools/objtool/check.c >>> >>> There is no other change to oops_end other than that renaming. >>> >>> Did the robot somehow mange to run an old version of objtool while >>> building and this get this error? >>> >>> I tried and I am not currently able to reproduce this error. Do you >>> have any additional pointers on how I might reproduce this? >> Hi Eric, >> >> The reproduce step in report based on a full build, I can reproduce >> the warnings with the below command: >> >>   make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash > Any chance you could do "make arch/x86/kernel/dumpstack.s" and send it > to me? $ make O=build_dir ARCH=x86_64 SHELL=/bin/bash arch/x86/kernel/dumpstack.s make[1]: Entering directory '/mnt/memdrive/linux/build_dir'   GEN     Makefile   CALL    ../scripts/checksyscalls.sh   CALL    ../scripts/atomic/check-atomics.sh   DESCEND objtool   CC      arch/x86/kernel/dumpstack.s make[1]: Leaving directory '/mnt/memdrive/linux/build_dir' $ make O=build_dir ARCH=x86_64 SHELL=/bin/bash arch/x86/kernel/ make[1]: Entering directory '/mnt/memdrive/linux/build_dir'   GEN     Makefile   CALL    ../scripts/checksyscalls.sh   CALL    ../scripts/atomic/check-atomics.sh   DESCEND objtool   CC      arch/x86/kernel/dumpstack.o arch/x86/kernel/dumpstack.o: warning: objtool: oops_end() falls through to next function show_opcodes()   AR      arch/x86/kernel/built-in.a make[1]: Leaving directory '/mnt/memdrive/linux/build_dir' Best Regards, Rong Chen > > I want to see what code is in your oops_end. > > It really does not make sense that simply renaming a function would > trigger this error. > > I did a full build (on debian 10 with gcc-8.3.0) and I did not manage to > reproduce this. In a bit I will try with a newer debian and see if I > can get the issue to reproduce. Still it does not make sense to me > that a simple rename would trigger this error. > > Eric >