From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757251AbcHZCdx (ORCPT ); Thu, 25 Aug 2016 22:33:53 -0400 Received: from mga07.intel.com ([134.134.136.100]:20414 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751745AbcHZCdt (ORCPT ); Thu, 25 Aug 2016 22:33:49 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,579,1464678000"; d="scan'208";a="161114069" Date: Fri, 26 Aug 2016 10:33:12 +0800 From: kbuild test robot To: Johannes Berg Cc: kbuild-all@01.org, linux-kernel@vger.kernel.org, Ingo Molnar , "Peter Zijlstra (Intel)" Subject: include/linux/radix-tree.h:199:16: sparse: expression using sizeof(void) Message-ID: <201608261000.ADncBbj4%fengguang.wu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: fengguang.wu@intel.com X-SA-Exim-Scanned: No (on bee); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 61c04572de404e52a655a36752e696bbcb483cf5 commit: 112dc0c8069e5554e0ad29c58228f1e6ca49e13d locking/barriers: Suppress sparse warnings in lockless_dereference() date: 8 days ago reproduce: # apt-get install sparse git checkout 112dc0c8069e5554e0ad29c58228f1e6ca49e13d make ARCH=x86_64 allmodconfig make C=1 CF=-D__CHECK_ENDIAN__ sparse warnings: (new ones prefixed by >>) >> include/linux/radix-tree.h:199:16: sparse: expression using sizeof(void) include/linux/radix-tree.h:199:16: sparse: incompatible types in comparison expression (different address spaces) vim +199 include/linux/radix-tree.h 7cf9c2c7 Nick Piggin 2006-12-06 183 7cf9c2c7 Nick Piggin 2006-12-06 184 /** 7cf9c2c7 Nick Piggin 2006-12-06 185 * radix_tree_deref_slot - dereference a slot 7cf9c2c7 Nick Piggin 2006-12-06 186 * @pslot: pointer to slot, returned by radix_tree_lookup_slot 7cf9c2c7 Nick Piggin 2006-12-06 187 * Returns: item that was stored in that slot with any direct pointer flag 7cf9c2c7 Nick Piggin 2006-12-06 188 * removed. 7cf9c2c7 Nick Piggin 2006-12-06 189 * 7cf9c2c7 Nick Piggin 2006-12-06 190 * For use with radix_tree_lookup_slot(). Caller must hold tree at least read 27d20fdd Nick Piggin 2010-11-11 191 * locked across slot lookup and dereference. Not required if write lock is 27d20fdd Nick Piggin 2010-11-11 192 * held (ie. items cannot be concurrently inserted). 27d20fdd Nick Piggin 2010-11-11 193 * 27d20fdd Nick Piggin 2010-11-11 194 * radix_tree_deref_retry must be used to confirm validity of the pointer if 27d20fdd Nick Piggin 2010-11-11 195 * only the read lock is held. 7cf9c2c7 Nick Piggin 2006-12-06 196 */ 7cf9c2c7 Nick Piggin 2006-12-06 197 static inline void *radix_tree_deref_slot(void **pslot) 7cf9c2c7 Nick Piggin 2006-12-06 198 { 27d20fdd Nick Piggin 2010-11-11 @199 return rcu_dereference(*pslot); 7cf9c2c7 Nick Piggin 2006-12-06 200 } 27d20fdd Nick Piggin 2010-11-11 201 27d20fdd Nick Piggin 2010-11-11 202 /** 29c1f677 Mel Gorman 2011-01-13 203 * radix_tree_deref_slot_protected - dereference a slot without RCU lock but with tree lock held 29c1f677 Mel Gorman 2011-01-13 204 * @pslot: pointer to slot, returned by radix_tree_lookup_slot 29c1f677 Mel Gorman 2011-01-13 205 * Returns: item that was stored in that slot with any direct pointer flag 29c1f677 Mel Gorman 2011-01-13 206 * removed. 29c1f677 Mel Gorman 2011-01-13 207 * :::::: The code at line 199 was first introduced by commit :::::: 27d20fddc8af539464fc3ba499d6a830054c3bd6 radix-tree: fix RCU bug :::::: TO: Nick Piggin :::::: CC: Linus Torvalds --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation