From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.codeaurora.org by pdx-caf-mail.web.codeaurora.org (Dovecot) with LMTP id idPRHXWmHFtLbAAAmS7hNA ; Sun, 10 Jun 2018 04:19:00 +0000 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id A1BC260795; Sun, 10 Jun 2018 04:19:00 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on pdx-caf-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by smtp.codeaurora.org (Postfix) with ESMTP id 0C8E56074D; Sun, 10 Jun 2018 04:18:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 0C8E56074D Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=zytor.com Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753682AbeFJES5 (ORCPT + 25 others); Sun, 10 Jun 2018 00:18:57 -0400 Received: from terminus.zytor.com ([198.137.202.136]:50001 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750744AbeFJES4 (ORCPT ); Sun, 10 Jun 2018 00:18:56 -0400 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id w5A4Iktc3241665 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Sat, 9 Jun 2018 21:18:46 -0700 Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id w5A4Ij4Q3241662; Sat, 9 Jun 2018 21:18:45 -0700 Date: Sat, 9 Jun 2018 21:18:45 -0700 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: tip-bot for Anna-Maria Gleixner Message-ID: Cc: ebiederm@xmission.com, anna-maria@linutronix.de, linux-kernel@vger.kernel.org, paulmck@linux.vnet.ibm.com, mingo@kernel.org, hpa@zytor.com, tglx@linutronix.de Reply-To: hpa@zytor.com, linux-kernel@vger.kernel.org, mingo@kernel.org, paulmck@linux.vnet.ibm.com, tglx@linutronix.de, anna-maria@linutronix.de, ebiederm@xmission.com In-Reply-To: <20180525090507.22248-2-anna-maria@linutronix.de> References: <20180525090507.22248-2-anna-maria@linutronix.de> To: linux-tip-commits@vger.kernel.org Subject: [tip:core/urgent] rcu: Update documentation of rcu_read_unlock() Git-Commit-ID: ec84b27f9b3b569f9235413d1945a2006b97b0aa 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: ec84b27f9b3b569f9235413d1945a2006b97b0aa Gitweb: https://git.kernel.org/tip/ec84b27f9b3b569f9235413d1945a2006b97b0aa Author: Anna-Maria Gleixner AuthorDate: Fri, 25 May 2018 11:05:06 +0200 Committer: Thomas Gleixner CommitDate: Sun, 10 Jun 2018 06:14:01 +0200 rcu: Update documentation of rcu_read_unlock() Since commit b4abf91047cf ("rtmutex: Make wait_lock irq safe") the explanation in rcu_read_unlock() documentation about irq unsafe rtmutex wait_lock is no longer valid. Remove it to prevent kernel developers reading the documentation to rely on it. Suggested-by: Eric W. Biederman Signed-off-by: Anna-Maria Gleixner Signed-off-by: Thomas Gleixner Reviewed-by: Paul E. McKenney Acked-by: "Eric W. Biederman" Cc: bigeasy@linutronix.de Link: https://lkml.kernel.org/r/20180525090507.22248-2-anna-maria@linutronix.de --- include/linux/rcupdate.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index e679b175b411..65163aa0bb04 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -652,9 +652,7 @@ static inline void rcu_read_lock(void) * Unfortunately, this function acquires the scheduler's runqueue and * priority-inheritance spinlocks. This means that deadlock could result * if the caller of rcu_read_unlock() already holds one of these locks or - * any lock that is ever acquired while holding them; or any lock which - * can be taken from interrupt context because rcu_boost()->rt_mutex_lock() - * does not disable irqs while taking ->wait_lock. + * any lock that is ever acquired while holding them. * * That said, RCU readers are never priority boosted unless they were * preempted. Therefore, one way to avoid deadlock is to make sure