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=-12.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 37DCEC43381 for ; Thu, 28 Feb 2019 07:05:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0FAA721850 for ; Thu, 28 Feb 2019 07:05:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731384AbfB1HFJ (ORCPT ); Thu, 28 Feb 2019 02:05:09 -0500 Received: from terminus.zytor.com ([198.137.202.136]:35221 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731129AbfB1HFI (ORCPT ); Thu, 28 Feb 2019 02:05:08 -0500 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id x1S74dHr2938111 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Wed, 27 Feb 2019 23:04:39 -0800 Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id x1S74dvu2938108; Wed, 27 Feb 2019 23:04:39 -0800 Date: Wed, 27 Feb 2019 23:04:39 -0800 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: tip-bot for Bart Van Assche Message-ID: Cc: johannes@sipsolutions.net, longman@redhat.com, linux-kernel@vger.kernel.org, hpa@zytor.com, paulmck@linux.vnet.ibm.com, mingo@kernel.org, peterz@infradead.org, tglx@linutronix.de, torvalds@linux-foundation.org, will.deacon@arm.com, akpm@linux-foundation.org, bvanassche@acm.org Reply-To: bvanassche@acm.org, akpm@linux-foundation.org, will.deacon@arm.com, torvalds@linux-foundation.org, tglx@linutronix.de, peterz@infradead.org, mingo@kernel.org, paulmck@linux.vnet.ibm.com, hpa@zytor.com, linux-kernel@vger.kernel.org, longman@redhat.com, johannes@sipsolutions.net In-Reply-To: <20190214230058.196511-5-bvanassche@acm.org> References: <20190214230058.196511-5-bvanassche@acm.org> To: linux-tip-commits@vger.kernel.org Subject: [tip:locking/core] locking/lockdep: Avoid that add_chain_cache() adds an invalid chain to the cache Git-Commit-ID: 523b113bace5e64e860d8c61d7aa25057d274753 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 523b113bace5e64e860d8c61d7aa25057d274753 Gitweb: https://git.kernel.org/tip/523b113bace5e64e860d8c61d7aa25057d274753 Author: Bart Van Assche AuthorDate: Thu, 14 Feb 2019 15:00:39 -0800 Committer: Ingo Molnar CommitDate: Thu, 28 Feb 2019 07:55:40 +0100 locking/lockdep: Avoid that add_chain_cache() adds an invalid chain to the cache Make sure that add_chain_cache() returns 0 and does not modify the chain hash if nr_chain_hlocks == MAX_LOCKDEP_CHAIN_HLOCKS before this function is called. Signed-off-by: Bart Van Assche Signed-off-by: Peter Zijlstra (Intel) Cc: Andrew Morton Cc: Johannes Berg Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Waiman Long Cc: Will Deacon Cc: johannes.berg@intel.com Cc: tj@kernel.org Link: https://lkml.kernel.org/r/20190214230058.196511-5-bvanassche@acm.org Signed-off-by: Ingo Molnar --- kernel/locking/lockdep.c | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index ec6f6aff4d8d..21d84510e28f 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -2195,16 +2195,8 @@ static inline int add_chain_cache(struct task_struct *curr, chain_hlocks[chain->base + j] = lock_id; } chain_hlocks[chain->base + j] = class - lock_classes; - } - - if (nr_chain_hlocks < MAX_LOCKDEP_CHAIN_HLOCKS) nr_chain_hlocks += chain->depth; - -#ifdef CONFIG_DEBUG_LOCKDEP - /* - * Important for check_no_collision(). - */ - if (unlikely(nr_chain_hlocks > MAX_LOCKDEP_CHAIN_HLOCKS)) { + } else { if (!debug_locks_off_graph_unlock()) return 0; @@ -2212,7 +2204,6 @@ static inline int add_chain_cache(struct task_struct *curr, dump_stack(); return 0; } -#endif hlist_add_head_rcu(&chain->entry, hash_head); debug_atomic_inc(chain_lookup_misses);