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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 46C4AC433F5 for ; Tue, 29 Mar 2022 06:33:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233077AbiC2Ger (ORCPT ); Tue, 29 Mar 2022 02:34:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60650 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233059AbiC2Gen (ORCPT ); Tue, 29 Mar 2022 02:34:43 -0400 Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B85FC199E12 for ; Mon, 28 Mar 2022 23:33:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1648535581; x=1680071581; h=date:from:to:cc:subject:message-id:mime-version; bh=b+xsrYYgRj8ZI/u2pSfAOvTw9v5HYhv+7RXB8v+73lk=; b=PyIVzbX71wesui4FDz5zixM0dm5Rc4UO9JnqjPOaWO6ARoip+mQL6hsK g7X4Z26jsEy/pfGavPjdGvgnWnRbB23i07wQxMdiMXswC1q3LqF/F1FH3 szog9CazcDOh9rP/mplh99LcLy4+YO8zSn883IWC0KxceDjl71AHxCKTc 2c86Tewp0StB9GiYDU99J+9RJbKY51FG5YBTuVM9m2B5g/56w+GbMW63/ Zn2vseU748M5FCpZaoZxiiFt4ZFJrVIdS8mBqCD8TZBb5Omaj8ZUvQbTP biFCz5c6bRDM/YwVPBj4/GsXa59+XJOT3/LRXms/wIfpBJfmucQOUeTjn w==; X-IronPort-AV: E=McAfee;i="6200,9189,10300"; a="241327959" X-IronPort-AV: E=Sophos;i="5.90,219,1643702400"; d="scan'208";a="241327959" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Mar 2022 23:33:01 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.90,219,1643702400"; d="scan'208";a="585457295" Received: from lkp-server02.sh.intel.com (HELO 89b41b6ae01c) ([10.239.97.151]) by orsmga001.jf.intel.com with ESMTP; 28 Mar 2022 23:32:59 -0700 Received: from kbuild by 89b41b6ae01c with local (Exim 4.92) (envelope-from ) id 1nZ5PW-0002kX-IA; Tue, 29 Mar 2022 06:32:58 +0000 Date: Tue, 29 Mar 2022 14:32:37 +0800 From: kernel test robot To: "Gustavo A. R. Silva" Cc: llvm@lists.linux.dev, kbuild-all@lists.01.org, "Gustavo A. R. Silva" , LKML Subject: [gustavoars:testing/kspp-stringop-overflow 5/5] arch/x86/mm/pgtable.c:442:27: warning: variable 'pmds' is uninitialized when used here Message-ID: <202203291404.IHkCx1AG-lkp@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org tree: https://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux.git testing/kspp-stringop-overflow head: d3becb16bbfe48ca524e4489b6c6c4fb1ccafa1a commit: d3becb16bbfe48ca524e4489b6c6c4fb1ccafa1a [5/5] mm/pgtable: Fix Wstringop-overflow warnings in pgd_alloc() config: i386-randconfig-a012-20220328 (https://download.01.org/0day-ci/archive/20220329/202203291404.IHkCx1AG-lkp@intel.com/config) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 0f6d9501cf49ce02937099350d08f20c4af86f3d) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # https://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux.git/commit/?id=d3becb16bbfe48ca524e4489b6c6c4fb1ccafa1a git remote add gustavoars https://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux.git git fetch --no-tags gustavoars testing/kspp-stringop-overflow git checkout d3becb16bbfe48ca524e4489b6c6c4fb1ccafa1a # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash arch/x86/mm/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): >> arch/x86/mm/pgtable.c:442:27: warning: variable 'pmds' is uninitialized when used here [-Wuninitialized] if (preallocate_pmds(mm, pmds, PREALLOCATED_PMDS) != 0) ^~~~ arch/x86/mm/pgtable.c:432:14: note: initialize the variable 'pmds' to silence this warning pmd_t **pmds; ^ = NULL >> arch/x86/mm/pgtable.c:445:27: warning: variable 'u_pmds' is uninitialized when used here [-Wuninitialized] if (preallocate_pmds(mm, u_pmds, PREALLOCATED_USER_PMDS) != 0) ^~~~~~ arch/x86/mm/pgtable.c:431:16: note: initialize the variable 'u_pmds' to silence this warning pmd_t **u_pmds; ^ = NULL 2 warnings generated. vim +/pmds +442 arch/x86/mm/pgtable.c 1ec1fe73dfb711 Ingo Molnar 2008-03-19 434 1db491f77b6ed0 Fenghua Yu 2015-01-15 435 pgd = _pgd_alloc(); 1ec1fe73dfb711 Ingo Molnar 2008-03-19 436 d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 437 if (pgd == NULL) d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 438 goto out; 4f76cd382213b2 Jeremy Fitzhardinge 2008-03-17 439 d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 440 mm->pgd = pgd; 4f76cd382213b2 Jeremy Fitzhardinge 2008-03-17 441 f59dbe9ca6707e Joerg Roedel 2018-07-18 @442 if (preallocate_pmds(mm, pmds, PREALLOCATED_PMDS) != 0) d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 443 goto out_free_pgd; d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 444 f59dbe9ca6707e Joerg Roedel 2018-07-18 @445 if (preallocate_pmds(mm, u_pmds, PREALLOCATED_USER_PMDS) != 0) d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 446 goto out_free_pmds; d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 447 f59dbe9ca6707e Joerg Roedel 2018-07-18 448 if (paravirt_pgd_alloc(mm) != 0) f59dbe9ca6707e Joerg Roedel 2018-07-18 449 goto out_free_user_pmds; f59dbe9ca6707e Joerg Roedel 2018-07-18 450 d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 451 /* d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 452 * Make sure that pre-populating the pmds is atomic with d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 453 * respect to anything walking the pgd_list, so that they d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 454 * never see a partially populated pgd. d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 455 */ a79e53d85683c6 Andrea Arcangeli 2011-02-16 456 spin_lock(&pgd_lock); 4f76cd382213b2 Jeremy Fitzhardinge 2008-03-17 457 617d34d9e5d832 Jeremy Fitzhardinge 2010-09-21 458 pgd_ctor(mm, pgd); d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 459 pgd_prepopulate_pmd(mm, pgd, pmds); f59dbe9ca6707e Joerg Roedel 2018-07-18 460 pgd_prepopulate_user_pmd(mm, pgd, u_pmds); 4f76cd382213b2 Jeremy Fitzhardinge 2008-03-17 461 a79e53d85683c6 Andrea Arcangeli 2011-02-16 462 spin_unlock(&pgd_lock); 4f76cd382213b2 Jeremy Fitzhardinge 2008-03-17 463 4f76cd382213b2 Jeremy Fitzhardinge 2008-03-17 464 return pgd; d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 465 f59dbe9ca6707e Joerg Roedel 2018-07-18 466 out_free_user_pmds: f59dbe9ca6707e Joerg Roedel 2018-07-18 467 free_pmds(mm, u_pmds, PREALLOCATED_USER_PMDS); d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 468 out_free_pmds: f59dbe9ca6707e Joerg Roedel 2018-07-18 469 free_pmds(mm, pmds, PREALLOCATED_PMDS); d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 470 out_free_pgd: 1db491f77b6ed0 Fenghua Yu 2015-01-15 471 _pgd_free(pgd); d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 472 out: d8d5900ef8afc5 Jeremy Fitzhardinge 2008-06-25 473 return NULL; 4f76cd382213b2 Jeremy Fitzhardinge 2008-03-17 474 } 4f76cd382213b2 Jeremy Fitzhardinge 2008-03-17 475 :::::: The code at line 442 was first introduced by commit :::::: f59dbe9ca6707eb7ffd0e24359085651c2d7df48 x86/pgtable/pae: Use separate kernel PMDs for user page-table :::::: TO: Joerg Roedel :::::: CC: Thomas Gleixner -- 0-DAY CI Kernel Test Service https://01.org/lkp