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=-11.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 019DBC43331 for ; Wed, 13 Nov 2019 10:57:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BFF06222BD for ; Wed, 13 Nov 2019 10:57:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727727AbfKMK5A (ORCPT ); Wed, 13 Nov 2019 05:57:00 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:37355 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727211AbfKMK46 (ORCPT ); Wed, 13 Nov 2019 05:56:58 -0500 Received: from [5.158.153.53] (helo=tip-bot2.lab.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1iUqKM-00026c-VW; Wed, 13 Nov 2019 11:56:47 +0100 Received: from [127.0.1.1] (localhost [IPv6:::1]) by tip-bot2.lab.linutronix.de (Postfix) with ESMTP id 9ABAE1C0357; Wed, 13 Nov 2019 11:56:46 +0100 (CET) Date: Wed, 13 Nov 2019 10:56:46 -0000 From: "tip-bot2 for Qian Cai" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: perf/core] perf/core: Fix unlock balance in perf_init_event() Cc: Qian Cai , "Peter Zijlstra (Intel)" , Alexander Shishkin , Arnaldo Carvalho de Melo , David Ahern , Jiri Olsa , Linus Torvalds , Mark Rutland , Namhyung Kim , Stephane Eranian , Thomas Gleixner , Vince Weaver , Ingo Molnar , Borislav Petkov , linux-kernel@vger.kernel.org In-Reply-To: <20191106052935.8352-1-cai@lca.pw> References: <20191106052935.8352-1-cai@lca.pw> MIME-Version: 1.0 Message-ID: <157364260624.29376.13060187465049038563.tip-bot2@tip-bot2> X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the perf/core branch of tip: Commit-ID: deb0c3c29d552ab81ecd5481bb83bf2f4e41927d Gitweb: https://git.kernel.org/tip/deb0c3c29d552ab81ecd5481bb83bf2f4e41927d Author: Qian Cai AuthorDate: Wed, 06 Nov 2019 00:29:35 -05:00 Committer: Ingo Molnar CommitterDate: Wed, 13 Nov 2019 11:06:13 +01:00 perf/core: Fix unlock balance in perf_init_event() Commit: 66d258c5b048 ("perf/core: Optimize perf_init_event()") introduced an unlock imbalance in perf_init_event() where it calls "goto again" and then only repeat rcu_read_unlock(). Signed-off-by: Qian Cai Signed-off-by: Peter Zijlstra (Intel) Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: David Ahern Cc: Jiri Olsa Cc: Linus Torvalds Cc: Mark Rutland Cc: Namhyung Kim Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Fixes: 66d258c5b048 ("perf/core: Optimize perf_init_event()") Link: https://lkml.kernel.org/r/20191106052935.8352-1-cai@lca.pw Signed-off-by: Ingo Molnar --- kernel/events/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 6cb6d68..8d65e03 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -10307,7 +10307,6 @@ static struct pmu *perf_init_event(struct perf_event *event) goto unlock; } - rcu_read_lock(); /* * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE * are often aliases for PERF_TYPE_RAW. @@ -10317,6 +10316,7 @@ static struct pmu *perf_init_event(struct perf_event *event) type = PERF_TYPE_RAW; again: + rcu_read_lock(); pmu = idr_find(&pmu_idr, type); rcu_read_unlock(); if (pmu) {