From patchwork Thu Dec 13 18:27:47 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 10729571 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 446CA14E2 for ; Thu, 13 Dec 2018 18:28:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 350E42BB7F for ; Thu, 13 Dec 2018 18:28:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 291762C81C; Thu, 13 Dec 2018 18:28:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7FDB72BB7F for ; Thu, 13 Dec 2018 18:28:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727749AbeLMS2J (ORCPT ); Thu, 13 Dec 2018 13:28:09 -0500 Received: from cloudserver094114.home.pl ([79.96.170.134]:57956 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727340AbeLMS2J (ORCPT ); Thu, 13 Dec 2018 13:28:09 -0500 Received: from 79.184.252.35.ipv4.supernova.orange.pl (79.184.252.35) (HELO aspire.rjw.lan) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.183) id ef3a5b3589861782; Thu, 13 Dec 2018 19:28:07 +0100 From: "Rafael J. Wysocki" To: Greg Kroah-Hartman Cc: Martin Liu , Alan Stern , LKML , Linux PM , Daniel Vetter Subject: [PATCH] driver core: Add missing dev->bus->need_parent_lock checks Date: Thu, 13 Dec 2018 19:27:47 +0100 Message-ID: <7586985.G9YL5ver76@aspire.rjw.lan> MIME-Version: 1.0 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Rafael J. Wysocki __device_release_driver() has to check dev->bus->need_parent_lock before dropping the parent lock and acquiring it again as it may attempt to drop a lock that hasn't been acquired or lock a device that shouldn't be locked and create a lock imbalance. Fixes: 8c97a46af04b (driver core: hold dev's parent lock when needed) Signed-off-by: Rafael J. Wysocki Reviewed-by: Daniel Vetter --- This should go into -stable for everything over 4.18 methinks. --- drivers/base/dd.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) Index: linux-pm/drivers/base/dd.c =================================================================== --- linux-pm.orig/drivers/base/dd.c +++ linux-pm/drivers/base/dd.c @@ -933,11 +933,11 @@ static void __device_release_driver(stru while (device_links_busy(dev)) { device_unlock(dev); - if (parent) + if (parent && dev->bus->need_parent_lock) device_unlock(parent); device_links_unbind_consumers(dev); - if (parent) + if (parent && dev->bus->need_parent_lock) device_lock(parent); device_lock(dev);