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 DD79BC43603 for ; Mon, 16 Dec 2019 18:04:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A484320700 for ; Mon, 16 Dec 2019 18:04:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576519441; bh=F2n07ws10lQmM2LodegTTQfMXCbscbF5aBDGHTmAry4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=AqL+7UpMTQWCzHsl0xGiVcFK62bMrRJFG3gQ/Gl9zwiwHoVQxtePEis9KZK78b1aE GfLyiZoa4KBnPbPU2S5hqL4Sjf9pHF3S+T3yY7HLmYVqIKms7QNcNWY3BTQcWfm5FZ kXT2tKifPoVGksGxhnGr535AVA3l/3LmrWRrjNFw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729603AbfLPSEA (ORCPT ); Mon, 16 Dec 2019 13:04:00 -0500 Received: from mail.kernel.org ([198.145.29.99]:41016 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729585AbfLPSD5 (ORCPT ); Mon, 16 Dec 2019 13:03:57 -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 A34F120700; Mon, 16 Dec 2019 18:03:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576519436; bh=F2n07ws10lQmM2LodegTTQfMXCbscbF5aBDGHTmAry4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RLbAPXU3HOAXoiZAnPZncFJvpesWBsh0KYhtJRb5yXJdeV2ixdJom6Hx4orxoWCTc w9JB8wTOC2TxxXqC0CxIk5Jd+3TWBfEq/xKbMLCYHcvpEEN3JQYT0JmLaF15Ena5Xq PhUBlJLThcN8AI0zH3kGy+LZV/PLXFMaxVGxeCQY= 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 4.19 066/140] cpuidle: Do not unset the driver if it is there already Date: Mon, 16 Dec 2019 18:48:54 +0100 Message-Id: <20191216174805.779293182@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191216174747.111154704@linuxfoundation.org> References: <20191216174747.111154704@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 @@ -62,24 +62,23 @@ 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; }