From patchwork Mon Sep 21 16:27:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "gregkh@linuxfoundation.org" X-Patchwork-Id: 309309 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=-11.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 48EAEC43466 for ; Mon, 21 Sep 2020 17:04:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0BEF32073A for ; Mon, 21 Sep 2020 17:04:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600707860; bh=28KYJg0fE24gkQosi9nTcNDuSlAc/moBv2YPkZX0E3g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=uKWLBbsAWim30PugRlQvi1WBsGHbWOk0exTN6SK81vPj7tB4VsfNgAz3sfrHQCfO1 3q3V0wG5b0VbxIMorD0yVrkD4SDibiHq82ODy83FOVc6Pbc0kYuLi+Y542r38fVUww t7ZD6u1lkGjiRnOMaiBkfK2ZYBhLUjxluaas7EY8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730298AbgIUREE (ORCPT ); Mon, 21 Sep 2020 13:04:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:35544 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728259AbgIUQf6 (ORCPT ); Mon, 21 Sep 2020 12:35:58 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 3B39E238EE; Mon, 21 Sep 2020 16:35:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600706157; bh=28KYJg0fE24gkQosi9nTcNDuSlAc/moBv2YPkZX0E3g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XWtvqM76yzgzvI67tm7rOa/+rYkw3AUJwazSjGNopayD9qhc5woAPLpqV+Ky3R/XT Cso17bFvlAYi9L99OBJTAwOfOeR7+XcC5EMaM5nZguFZKfdX3H/+PGfJlHoNGiCj4C e5aJPFRyA32Q2KEkAESLcWgxssMBEOjzV61SLVuo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?utf-8?b?TWljaGHFgiBNaXJvc8WCYXc=?= , Mark Brown Subject: [PATCH 4.9 31/70] regulator: push allocation in set_consumer_device_supply() out of lock Date: Mon, 21 Sep 2020 18:27:31 +0200 Message-Id: <20200921162036.545540754@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200921162035.136047591@linuxfoundation.org> References: <20200921162035.136047591@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Michał Mirosław commit 5c06540165d443c6455123eb48e7f1a9b618ab34 upstream. Pull regulator_list_mutex into set_consumer_device_supply() and keep allocations outside of it. Fourth of the fs_reclaim deadlock case. Fixes: 45389c47526d ("regulator: core: Add early supply resolution for regulators") Signed-off-by: Michał Mirosław Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/f0380bdb3d60aeefa9693c4e234d2dcda7e56747.1597195321.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- drivers/regulator/core.c | 46 ++++++++++++++++++++++++++-------------------- 1 file changed, 26 insertions(+), 20 deletions(-) --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1191,7 +1191,7 @@ static int set_consumer_device_supply(st const char *consumer_dev_name, const char *supply) { - struct regulator_map *node; + struct regulator_map *node, *new_node; int has_dev; if (supply == NULL) @@ -1202,6 +1202,22 @@ static int set_consumer_device_supply(st else has_dev = 0; + new_node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL); + if (new_node == NULL) + return -ENOMEM; + + new_node->regulator = rdev; + new_node->supply = supply; + + if (has_dev) { + new_node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL); + if (new_node->dev_name == NULL) { + kfree(new_node); + return -ENOMEM; + } + } + + mutex_lock(®ulator_list_mutex); list_for_each_entry(node, ®ulator_map_list, list) { if (node->dev_name && consumer_dev_name) { if (strcmp(node->dev_name, consumer_dev_name) != 0) @@ -1219,26 +1235,19 @@ static int set_consumer_device_supply(st node->regulator->desc->name, supply, dev_name(&rdev->dev), rdev_get_name(rdev)); - return -EBUSY; + goto fail; } - node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL); - if (node == NULL) - return -ENOMEM; - - node->regulator = rdev; - node->supply = supply; - - if (has_dev) { - node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL); - if (node->dev_name == NULL) { - kfree(node); - return -ENOMEM; - } - } + list_add(&new_node->list, ®ulator_map_list); + mutex_unlock(®ulator_list_mutex); - list_add(&node->list, ®ulator_map_list); return 0; + +fail: + mutex_unlock(®ulator_list_mutex); + kfree(new_node->dev_name); + kfree(new_node); + return -EBUSY; } static void unset_regulator_supplies(struct regulator_dev *rdev) @@ -4034,19 +4043,16 @@ regulator_register(const struct regulato /* add consumers devices */ if (init_data) { - mutex_lock(®ulator_list_mutex); for (i = 0; i < init_data->num_consumer_supplies; i++) { ret = set_consumer_device_supply(rdev, init_data->consumer_supplies[i].dev_name, init_data->consumer_supplies[i].supply); if (ret < 0) { - mutex_unlock(®ulator_list_mutex); dev_err(dev, "Failed to set supply %s\n", init_data->consumer_supplies[i].supply); goto unset_supplies; } } - mutex_unlock(®ulator_list_mutex); } if (!rdev->desc->ops->get_voltage &&