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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 1EB81C2D0D1 for ; Thu, 19 Dec 2019 18:47:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E9D5024680 for ; Thu, 19 Dec 2019 18:47:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576781224; bh=thMYs7Pso3z3nCP5kKe2+F7DwqxhPwkfJ29Py85+nNg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=PtNQX6fd7mZdeVXx1bDNQa+U7N88avMkrXpN4PJsRoz1jAZcQKg+CagfHltIHLtlo 7LQWt/6zaIBb7u5SLU2u3uPNeh08YS9CIKIFQprt23Crj+lx3hmqfJrUj9X/ysc4+t czDLgXFjarpcHqpLHxKF8cRBBPk4HRHbOD6YzWZ0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729003AbfLSSrC (ORCPT ); Thu, 19 Dec 2019 13:47:02 -0500 Received: from mail.kernel.org ([198.145.29.99]:39898 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729406AbfLSSrB (ORCPT ); Thu, 19 Dec 2019 13:47:01 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CF161222C2; Thu, 19 Dec 2019 18:47:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576781221; bh=thMYs7Pso3z3nCP5kKe2+F7DwqxhPwkfJ29Py85+nNg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=m+2rFN3j0fppUI7HKime6c7p6JXR5w+upInWM38A//xWK2mSYbdMVoNf+Bxw76odA 7ejoKwHbkHCAbFi9BGdKOOfuesiAcTReP8XO2iT7J34uF6GqDfDWCrJD61dEePF0Vy CzQ6ixA/DJn8kWxFP2nEGCwrgu70JT1AWUe51vtw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Zhenzhong Duan , "Rafael J. Wysocki" Subject: [PATCH 4.9 133/199] cpuidle: Do not unset the driver if it is there already Date: Thu, 19 Dec 2019 19:33:35 +0100 Message-Id: <20191219183222.434745018@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191219183214.629503389@linuxfoundation.org> References: <20191219183214.629503389@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Zhenzhong Duan commit 918c1fe9fbbe46fcf56837ff21f0ef96424e8b29 upstream. Fix __cpuidle_set_driver() to check if any of the CPUs in the mask has a driver different from drv already and, if so, return -EBUSY before updating any cpuidle_drivers per-CPU pointers. Fixes: 82467a5a885d ("cpuidle: simplify multiple driver support") Cc: 3.11+ # 3.11+ Signed-off-by: Zhenzhong Duan [ rjw: Subject & changelog ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/cpuidle/driver.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) --- a/drivers/cpuidle/driver.c +++ b/drivers/cpuidle/driver.c @@ -61,24 +61,23 @@ static inline void __cpuidle_unset_drive * __cpuidle_set_driver - set per CPU driver variables for the given driver. * @drv: a valid pointer to a struct cpuidle_driver * - * For each CPU in the driver's cpumask, unset the registered driver per CPU - * to @drv. - * - * Returns 0 on success, -EBUSY if the CPUs have driver(s) already. + * Returns 0 on success, -EBUSY if any CPU in the cpumask have a driver + * different from drv already. */ static inline int __cpuidle_set_driver(struct cpuidle_driver *drv) { int cpu; for_each_cpu(cpu, drv->cpumask) { + struct cpuidle_driver *old_drv; - if (__cpuidle_get_cpu_driver(cpu)) { - __cpuidle_unset_driver(drv); + old_drv = __cpuidle_get_cpu_driver(cpu); + if (old_drv && old_drv != drv) return -EBUSY; - } + } + for_each_cpu(cpu, drv->cpumask) per_cpu(cpuidle_drivers, cpu) = drv; - } return 0; }