From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ED11AC43603 for ; Fri, 13 Dec 2019 21:19:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 61D7A206C3 for ; Fri, 13 Dec 2019 21:19:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726781AbfLMVTE (ORCPT ); Fri, 13 Dec 2019 16:19:04 -0500 Received: from mga05.intel.com ([192.55.52.43]:59024 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726313AbfLMVTE (ORCPT ); Fri, 13 Dec 2019 16:19:04 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 13 Dec 2019 13:19:03 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,311,1571727600"; d="scan'208";a="297039087" Received: from smile.fi.intel.com (HELO smile) ([10.237.68.40]) by orsmga001.jf.intel.com with ESMTP; 13 Dec 2019 13:19:01 -0800 Received: from andy by smile with local (Exim 4.93-RC7) (envelope-from ) id 1ifsKz-0004Nt-KV; Fri, 13 Dec 2019 23:19:01 +0200 Date: Fri, 13 Dec 2019 23:19:01 +0200 From: Andy Shevchenko To: Max Filippov Cc: kbuild test robot , kbuild-all@lists.01.org, LKML , Andrew Morton , Linux Memory Management List Subject: Re: WARNING: lib/test_bitmap.o(.text.unlikely+0x5c): Section mismatch in reference from the function bitmap_copy_clear_tail() to the variable .init.rodata:clump_exp Message-ID: <20191213211901.GL32742@smile.fi.intel.com> References: <201912100401.fDYi5lhU%lkp@intel.com> <20191213111649.GU32742@smile.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 13, 2019 at 01:08:08PM -0800, Max Filippov wrote: > On Fri, Dec 13, 2019 at 3:16 AM Andy Shevchenko > wrote: > > On Tue, Dec 10, 2019 at 04:17:03AM +0800, kbuild test robot wrote: > > > > +Cc: Max for xtensa matters, perhaps he has an idea. > > > > > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master > > > head: e42617b825f8073569da76dc4510bfa019b1c35a > > > commit: 30544ed5de431fe25d3793e4dd5a058d877c4d77 lib/bitmap: introduce bitmap_replace() helper > > > date: 5 days ago > > > config: xtensa-randconfig-a001-20191209 (attached as .config) > > > compiler: xtensa-linux-gcc (GCC) 7.5.0 > > > reproduce: > > > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross > > > chmod +x ~/bin/make.cross > > > git checkout 30544ed5de431fe25d3793e4dd5a058d877c4d77 > > > # save the attached .config to linux build tree > > > GCC_VERSION=7.5.0 make.cross ARCH=xtensa > > > > > > If you fix the issue, kindly add following tag > > > Reported-by: kbuild test robot > > > > > > All warnings (new ones prefixed by >>): > > > > I'm not sure I got this (esp. relation to my patch). > > The mentioned code definitely compiled for 32-bit (since only then mentioned > > bitmap API is in use). I have tried to reproduce on i386 compilation (gcc 9.x), > > but can't. > > I was able to reproduce it on xtensa with gcc-9. > The issue comes from the test "test_replace", specifically > from the following call: > bitmap_replace(bmap, &exp2[0], &exp2[1], exp2_to_exp3_mask, nbits); > > An invariable part of the call sequence used here is instantiated in > the section .text.unlikely with a reference to exp2_to_exp3_mask built > into it and it's called from the test_replace. It looks like a compiler bug > to me, I'd expect this code to be emitted to the .init.text, i.e the same > section where the function it was hoisted from resides. > And why "unlikely"? This code is definitely executed. > > I'll file a bug against gcc. Thanks for an analysis and quick response! -- With Best Regards, Andy Shevchenko