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=-14.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,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 0EFE6C433DF for ; Fri, 9 Oct 2020 07:58:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A8E87222EB for ; Fri, 9 Oct 2020 07:58:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="YYtKi4c/"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="59TlZJNh" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732504AbgJIH6y (ORCPT ); Fri, 9 Oct 2020 03:58:54 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:56112 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732456AbgJIH6p (ORCPT ); Fri, 9 Oct 2020 03:58:45 -0400 Date: Fri, 09 Oct 2020 07:58:41 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1602230322; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RHIOtxnDP1JZxo+W+QrNBZd4wcFwXbIcUS4t4cyZsNI=; b=YYtKi4c/ljyfYsFXVOORAL9ZlJ6iHhPlo5cEW8odmSbEud6Y/a3IzKnU2SOxoIpFurNlbC nq7OBd2sx1d1e7m2A7teKAT7HkvOf/rnJdJ3gutauotoZAkVD4BdCYYmDracav0bmZX8V0 4WgS0LToVjHoahTbfszy83BVdUd+kvfrNa1OxNOKOseyRwudNPhzgBAmasqmIhTUHYh1aB hQJf8TTA0/T740qza9Q8FqlVg9dRIyQqd520lvUgi7gpiSZSAglqC+lyNxYYqaOPSYTTJS KCDCJjj7gXhMr2PCmasD423nl0pBAYGuqz4NTzFtJTF3Z9S00kvuXjzbzBb4nA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1602230322; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RHIOtxnDP1JZxo+W+QrNBZd4wcFwXbIcUS4t4cyZsNI=; b=59TlZJNhsXcwbN7oEhvpdAeGTe/Meg5FY4IKDkI7YoxMGkoVvZryjqiTjUDlSFrsItQiks vhv+zbEZxpPKDuBQ== From: "tip-bot2 for Peter Zijlstra" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: locking/core] lockdep: Fix usage_traceoverflow Cc: Qian Cai , "Peter Zijlstra (Intel)" , Ingo Molnar , x86 , LKML In-Reply-To: <20200930094937.GE2651@hirez.programming.kicks-ass.net> References: <20200930094937.GE2651@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Message-ID: <160223032171.7002.8334463802918365937.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the locking/core branch of tip: Commit-ID: 2bb8945bcc1a768f2bc402a16c9610bba8d5187d Gitweb: https://git.kernel.org/tip/2bb8945bcc1a768f2bc402a16c9610bba8d5187d Author: Peter Zijlstra AuthorDate: Wed, 30 Sep 2020 11:49:37 +02:00 Committer: Ingo Molnar CommitterDate: Fri, 09 Oct 2020 08:53:08 +02:00 lockdep: Fix usage_traceoverflow Basically print_lock_class_header()'s for loop is out of sync with the the size of of ->usage_traces[]. Also clean things up a bit while at it, to avoid such mishaps in the future. Fixes: 23870f122768 ("locking/lockdep: Fix "USED" <- "IN-NMI" inversions") Reported-by: Qian Cai Debugged-by: Boqun Feng Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Tested-by: Qian Cai Link: https://lkml.kernel.org/r/20200930094937.GE2651@hirez.programming.kicks-ass.net --- include/linux/lockdep_types.h | 8 +++++-- kernel/locking/lockdep.c | 32 +++++++++++++---------------- kernel/locking/lockdep_internals.h | 7 ++++-- 3 files changed, 26 insertions(+), 21 deletions(-) diff --git a/include/linux/lockdep_types.h b/include/linux/lockdep_types.h index bb35b44..9a1fd49 100644 --- a/include/linux/lockdep_types.h +++ b/include/linux/lockdep_types.h @@ -35,8 +35,12 @@ enum lockdep_wait_type { /* * We'd rather not expose kernel/lockdep_states.h this wide, but we do need * the total number of states... :-( + * + * XXX_LOCK_USAGE_STATES is the number of lines in lockdep_states.h, for each + * of those we generates 4 states, Additionally we report on USED and USED_READ. */ -#define XXX_LOCK_USAGE_STATES (1+2*4) +#define XXX_LOCK_USAGE_STATES 2 +#define LOCK_TRACE_STATES (XXX_LOCK_USAGE_STATES*4 + 2) /* * NR_LOCKDEP_CACHING_CLASSES ... Number of classes @@ -106,7 +110,7 @@ struct lock_class { * IRQ/softirq usage tracking bits: */ unsigned long usage_mask; - const struct lock_trace *usage_traces[XXX_LOCK_USAGE_STATES]; + const struct lock_trace *usage_traces[LOCK_TRACE_STATES]; /* * Generation counter, when doing certain classes of graph walking, diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 2facbbd..a430fbb 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -585,6 +585,8 @@ static const char *usage_str[] = #include "lockdep_states.h" #undef LOCKDEP_STATE [LOCK_USED] = "INITIAL USE", + [LOCK_USED_READ] = "INITIAL READ USE", + /* abused as string storage for verify_lock_unused() */ [LOCK_USAGE_STATES] = "IN-NMI", }; #endif @@ -1939,7 +1941,7 @@ static void print_lock_class_header(struct lock_class *class, int depth) #endif printk(KERN_CONT " {\n"); - for (bit = 0; bit < LOCK_USAGE_STATES; bit++) { + for (bit = 0; bit < LOCK_TRACE_STATES; bit++) { if (class->usage_mask & (1 << bit)) { int len = depth; @@ -3969,7 +3971,7 @@ static int separate_irq_context(struct task_struct *curr, static int mark_lock(struct task_struct *curr, struct held_lock *this, enum lock_usage_bit new_bit) { - unsigned int old_mask, new_mask, ret = 1; + unsigned int new_mask, ret = 1; if (new_bit >= LOCK_USAGE_STATES) { DEBUG_LOCKS_WARN_ON(1); @@ -3996,30 +3998,26 @@ static int mark_lock(struct task_struct *curr, struct held_lock *this, if (unlikely(hlock_class(this)->usage_mask & new_mask)) goto unlock; - old_mask = hlock_class(this)->usage_mask; hlock_class(this)->usage_mask |= new_mask; - /* - * Save one usage_traces[] entry and map both LOCK_USED and - * LOCK_USED_READ onto the same entry. - */ - if (new_bit == LOCK_USED || new_bit == LOCK_USED_READ) { - if (old_mask & (LOCKF_USED | LOCKF_USED_READ)) - goto unlock; - new_bit = LOCK_USED; + if (new_bit < LOCK_TRACE_STATES) { + if (!(hlock_class(this)->usage_traces[new_bit] = save_trace())) + return 0; } - if (!(hlock_class(this)->usage_traces[new_bit] = save_trace())) - return 0; - switch (new_bit) { + case 0 ... LOCK_USED-1: + ret = mark_lock_irq(curr, this, new_bit); + if (!ret) + return 0; + break; + case LOCK_USED: debug_atomic_dec(nr_unused_locks); break; + default: - ret = mark_lock_irq(curr, this, new_bit); - if (!ret) - return 0; + break; } unlock: diff --git a/kernel/locking/lockdep_internals.h b/kernel/locking/lockdep_internals.h index b0be156..de49f9e 100644 --- a/kernel/locking/lockdep_internals.h +++ b/kernel/locking/lockdep_internals.h @@ -20,9 +20,12 @@ enum lock_usage_bit { #undef LOCKDEP_STATE LOCK_USED, LOCK_USED_READ, - LOCK_USAGE_STATES + LOCK_USAGE_STATES, }; +/* states after LOCK_USED_READ are not traced and printed */ +static_assert(LOCK_TRACE_STATES == LOCK_USAGE_STATES); + #define LOCK_USAGE_READ_MASK 1 #define LOCK_USAGE_DIR_MASK 2 #define LOCK_USAGE_STATE_MASK (~(LOCK_USAGE_READ_MASK | LOCK_USAGE_DIR_MASK)) @@ -121,7 +124,7 @@ static const unsigned long LOCKF_USED_IN_IRQ_READ = extern struct list_head all_lock_classes; extern struct lock_chain lock_chains[]; -#define LOCK_USAGE_CHARS (1+LOCK_USAGE_STATES/2) +#define LOCK_USAGE_CHARS (2*XXX_LOCK_USAGE_STATES + 1) extern void get_usage_chars(struct lock_class *class, char usage[LOCK_USAGE_CHARS]);