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=-8.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 F00CDC43387 for ; Wed, 9 Jan 2019 21:04:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B3D41206BB for ; Wed, 9 Jan 2019 21:04:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=mailprotect.be header.i=@mailprotect.be header.b="QDAzg0wO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728085AbfAIVE1 (ORCPT ); Wed, 9 Jan 2019 16:04:27 -0500 Received: from out002.mailprotect.be ([83.217.72.86]:42915 "EHLO out002.mailprotect.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727434AbfAIVCy (ORCPT ); Wed, 9 Jan 2019 16:02:54 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mailprotect.be; s=mail; h=Content-Transfer-Encoding:MIME-Version:References :In-Reply-To:Message-Id:Date:Subject:Cc:To:From:reply-to:sender:bcc: content-type; bh=gz+c7T7GOW633FMGLDVxyReVbF0BgqqCDpXDgDcsmZU=; b=QDAzg0wO9Gew 6p6NWkz7e9Vl0w2ofMG/1REGslJTRJc7mNOjgsXvxpRwbqdZphL2IB7IqMejjkA1hnLQKHrw3DMyZ k/VxG2aDr0gd4b8PNyo+XXFZ7JvErEce2QKrWsLkhumKCz1mGPEHkKYwNawjjeNyeaa7Lrv5196xC eMUraQEXXOmk7mgpocgaUrMj68gWFVzNzPpOf4P+2pC1IyijVjBPmr97WEcYJCQGGOUpSf0s2WGTQ S2DNqgKudC6PVTpihUCzYKnP28DXxXkVKj8OyAa6vKKVwO/fYRaRy1/6THcICg8pwnzYCtrCxbiEc ZzuJmW7Ke5vTMmtrJkg4uw==; Received: from smtp-auth.mailprotect.be ([178.208.39.159]) by com-mpt-out002.mailprotect.be with esmtp (Exim 4.89) (envelope-from ) id 1ghKzn-0009Ce-F2; Wed, 09 Jan 2019 22:02:40 +0100 Received: from desktop-bart.svl.corp.google.com (unknown [104.133.8.89]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp-auth.mailprotect.be (Postfix) with ESMTPSA id 6CDF9C15F1; Wed, 9 Jan 2019 22:02:23 +0100 (CET) From: Bart Van Assche To: peterz@infradead.org Cc: mingo@redhat.com, tj@kernel.org, longman@redhat.com, johannes.berg@intel.com, linux-kernel@vger.kernel.org, Bart Van Assche , Johannes Berg Subject: [PATCH v6 03/16] locking/lockdep: Make zap_class() remove all matching lock order entries Date: Wed, 9 Jan 2019 13:01:51 -0800 Message-Id: <20190109210204.192109-4-bvanassche@acm.org> X-Mailer: git-send-email 2.20.1.97.g81188d93c3-goog In-Reply-To: <20190109210204.192109-1-bvanassche@acm.org> References: <20190109210204.192109-1-bvanassche@acm.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Originating-IP: 178.208.39.159 X-SpamExperts-Domain: mailprotect.be X-SpamExperts-Username: 178.208.39.128/27 Authentication-Results: mailprotect.be; auth=pass smtp.auth=178.208.39.128/27@mailprotect.be X-SpamExperts-Outgoing-Class: ham X-SpamExperts-Outgoing-Evidence: Combined (0.03) X-Recommended-Action: accept X-Filter-ID: EX5BVjFpneJeBchSMxfU5hA/aS4EuEn7BhjIUVbLMpZ602E9L7XzfQH6nu9C/Fh9KJzpNe6xgvOx q3u0UDjvO1tLifGj39bI0bcPyaJsYTb/+zriNZuqQk0xRpGwjn+MTR8dtByWYYhgj25jR+mEA3YO AtfhCcV13BpIh8lqRXSSiFVwqwU9VgKUrYQ0lqWyFDaym8oavoPYsm7m1mVEGf0/5ST3nkt5XYDK YAuRpmF7E2F3eqKXiTd2ECUghryWXlqwG31yUGf3t09vBVYS71V1Pk0aHudBU1wyWVTA5OYS1waI XXCBiQFDV0yen8nGcSeERs4TOTnIH1kc1IWc5eLazqbUYkjl7F1LyK0RORqWM32AItFObsAtCbZS TT1RSNgvEAWLFiDAlQR6Wu0I/iWDegq4fQ11AxLVlrI7DVH6GzPz+r852EXXeYX4ImMyzDg6HYuT CyYgL61SIkBTYXPEvhymCNb22qmKERGbL1SqvGGff0htQqhQf0/aDrhpLM4xnCPpmyyS7jgD9Nen VVoB/PLX+rmdznc91veCJAwpCI+5VHpzDqRcT2+GtIE8SRAgmLDKAcp9i+Q+BEiSUj07SNjVkl0P Pj+OUYZX3/1fKPQPEuPra72LpiTN2rUT6Y9xm3kmEG6YzhU+GhpkbBQllJXXeGX8fAMzPNqrCG8d f68W0InH/+bTMKNm38MHmfnhF9U/dVeZ9xbDBH3UiCDt3yfQxlhCaKc8coJFU+8pOMQJvQ/Ck3ii U+4DQAj38VcpxSBd167NiiR0DMS/T4GvZUhi7BJ7QOeRk66G/m8jRjgifve2wm5/91NPphLvwdjs knqyEbjDKViNADzUevfG9Bh3rY3E1fk/gwQQ70WqltsYPx2OGpapJQwbU6lxiSPQp1QN34zBsoOP LAVTMEsOC75ReJHeVybconOP07vieGH1wwKQhUuVJ6kr80wTGaiTXW7z2lMqAnbumOwh0pBt+CpM AQh13vqug5h3DxxGoN9Ok9QgavkxBN81FyM027EnVMwCxJ89QGE/4wVOzpIAiDKO1d3jsySf+J0s zc1uD9pAwuLhqtxw5exj8Aw7fqb5R4VemuUI6bcEARsm0JyPNwoZFF/BeruF9IPYgMLyX2cd5RrN VWdImRunoKaV5Izq4VabSfIGUY8RJ38dSGEP+JYPRX76oPSBtBBPLYw1mZQfhvSXPX1npIQpGBE7 MnJiHvQ8gQs8eCOaG4DvtrnB4hxWBV/7jCqhcJq0hur2OKHH5lr9xXvSM4nM3avg X-Report-Abuse-To: spam@com-mpt-mgt001.mailprotect.be Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Make sure that all lock order entries that refer to a class are removed from the list_entries[] array when a kernel module is unloaded. Cc: Peter Zijlstra Cc: Waiman Long Cc: Johannes Berg Signed-off-by: Bart Van Assche --- include/linux/lockdep.h | 1 + kernel/locking/lockdep.c | 19 +++++++++++++------ 2 files changed, 14 insertions(+), 6 deletions(-) diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index c5335df2372f..71caa1118f4c 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -178,6 +178,7 @@ static inline void lockdep_copy_map(struct lockdep_map *to, struct lock_list { struct list_head entry; struct lock_class *class; + struct lock_class *links_to; struct stack_trace trace; int distance; diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 7a7c2d7b01c2..e52ce8745cba 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -859,7 +859,8 @@ static struct lock_list *alloc_list_entry(void) /* * Add a new dependency to the head of the list: */ -static int add_lock_to_list(struct lock_class *this, struct list_head *head, +static int add_lock_to_list(struct lock_class *this, + struct lock_class *links_to, struct list_head *head, unsigned long ip, int distance, struct stack_trace *trace) { @@ -873,6 +874,7 @@ static int add_lock_to_list(struct lock_class *this, struct list_head *head, return 0; entry->class = this; + entry->links_to = links_to; entry->distance = distance; entry->trace = *trace; /* @@ -1918,14 +1920,14 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev, * Ok, all validations passed, add the new lock * to the previous lock's dependency list: */ - ret = add_lock_to_list(hlock_class(next), + ret = add_lock_to_list(hlock_class(next), hlock_class(prev), &hlock_class(prev)->locks_after, next->acquire_ip, distance, trace); if (!ret) return 0; - ret = add_lock_to_list(hlock_class(prev), + ret = add_lock_to_list(hlock_class(prev), hlock_class(next), &hlock_class(next)->locks_before, next->acquire_ip, distance, trace); if (!ret) @@ -4119,15 +4121,20 @@ void lockdep_reset(void) */ static void zap_class(struct lock_class *class) { + struct lock_list *entry; int i; /* * Remove all dependencies this lock is * involved in: */ - for (i = 0; i < nr_list_entries; i++) { - if (list_entries[i].class == class) - list_del_rcu(&list_entries[i].entry); + for (i = 0, entry = list_entries; i < nr_list_entries; i++, entry++) { + if (entry->class != class && entry->links_to != class) + continue; + list_del_rcu(&entry->entry); + /* Clear .class and .links_to to avoid double removal. */ + WRITE_ONCE(entry->class, NULL); + WRITE_ONCE(entry->links_to, NULL); } /* * Unhash the class and remove it from the all_lock_classes list: -- 2.20.1.97.g81188d93c3-goog