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=-7.2 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,UNWANTED_LANGUAGE_BODY,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 473DEC433F7 for ; Mon, 20 Jul 2020 15:39:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1D66F22CB3 for ; Mon, 20 Jul 2020 15:39:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595259575; bh=5PEKRoAOKVBycOnhm8UGdi1OJVGEjJ+BLfGgfmXXvxw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=bYA1XBoz+gmxZ3TMBZ9voisRfPhh3xLRGzR3oZN54vXIKrVK1iY9EMBgJLzAe2Vi7 d5l/IfZkCxGS+U5sfoP8X6XsJr9iH9XLqBLQ3TAJHXrtQ/TWQepAyHbqzMVsCNBX9T LrRdVqNNmeVIXFpC129wx2BOYEckTKS47sEBGpK8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729529AbgGTPje (ORCPT ); Mon, 20 Jul 2020 11:39:34 -0400 Received: from mail.kernel.org ([198.145.29.99]:58626 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729512AbgGTPjc (ORCPT ); Mon, 20 Jul 2020 11:39:32 -0400 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 045DF22CBB; Mon, 20 Jul 2020 15:39:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595259571; bh=5PEKRoAOKVBycOnhm8UGdi1OJVGEjJ+BLfGgfmXXvxw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Sof0Tx7Ihe0HoQGL7w9LDcBwLyMkquISBFZNXJe8HCw/ihNmKSsFwCQXdpDqT8n05 +XJMt6wFgg+TolyY3SL4znfuH3HzH8NTCs7EYIsspKFA611eYFFCjrnhgf20LhZ4Wo v/+pvy6ccZv96/RWUodhQrBZMfru/jsOzOSuHEAQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Micha=C5=82=20Miros=C5=82aw?= Subject: [PATCH 4.4 57/58] misc: atmel-ssc: lock with mutex instead of spinlock Date: Mon, 20 Jul 2020 17:37:13 +0200 Message-Id: <20200720152750.111855945@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200720152747.127988571@linuxfoundation.org> References: <20200720152747.127988571@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: Michał Mirosław commit b037d60a3b1d1227609fd858fa34321f41829911 upstream. Uninterruptible context is not needed in the driver and causes lockdep warning because of mutex taken in of_alias_get_id(). Convert the lock to mutex to avoid the issue. Cc: stable@vger.kernel.org Fixes: 099343c64e16 ("ARM: at91: atmel-ssc: add device tree support") Signed-off-by: Michał Mirosław Link: https://lore.kernel.org/r/50f0d7fa107f318296afb49477c3571e4d6978c5.1592998403.git.mirq-linux@rere.qmqm.pl Signed-off-by: Greg Kroah-Hartman --- drivers/misc/atmel-ssc.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) --- a/drivers/misc/atmel-ssc.c +++ b/drivers/misc/atmel-ssc.c @@ -13,7 +13,7 @@ #include #include #include -#include +#include #include #include #include @@ -21,7 +21,7 @@ #include /* Serialize access to ssc_list and user count */ -static DEFINE_SPINLOCK(user_lock); +static DEFINE_MUTEX(user_lock); static LIST_HEAD(ssc_list); struct ssc_device *ssc_request(unsigned int ssc_num) @@ -29,7 +29,7 @@ struct ssc_device *ssc_request(unsigned int ssc_valid = 0; struct ssc_device *ssc; - spin_lock(&user_lock); + mutex_lock(&user_lock); list_for_each_entry(ssc, &ssc_list, list) { if (ssc->pdev->dev.of_node) { if (of_alias_get_id(ssc->pdev->dev.of_node, "ssc") @@ -44,18 +44,18 @@ struct ssc_device *ssc_request(unsigned } if (!ssc_valid) { - spin_unlock(&user_lock); + mutex_unlock(&user_lock); pr_err("ssc: ssc%d platform device is missing\n", ssc_num); return ERR_PTR(-ENODEV); } if (ssc->user) { - spin_unlock(&user_lock); + mutex_unlock(&user_lock); dev_dbg(&ssc->pdev->dev, "module busy\n"); return ERR_PTR(-EBUSY); } ssc->user++; - spin_unlock(&user_lock); + mutex_unlock(&user_lock); clk_prepare(ssc->clk); @@ -67,14 +67,14 @@ void ssc_free(struct ssc_device *ssc) { bool disable_clk = true; - spin_lock(&user_lock); + mutex_lock(&user_lock); if (ssc->user) ssc->user--; else { disable_clk = false; dev_dbg(&ssc->pdev->dev, "device already free\n"); } - spin_unlock(&user_lock); + mutex_unlock(&user_lock); if (disable_clk) clk_unprepare(ssc->clk); @@ -194,9 +194,9 @@ static int ssc_probe(struct platform_dev return -ENXIO; } - spin_lock(&user_lock); + mutex_lock(&user_lock); list_add_tail(&ssc->list, &ssc_list); - spin_unlock(&user_lock); + mutex_unlock(&user_lock); platform_set_drvdata(pdev, ssc); @@ -210,9 +210,9 @@ static int ssc_remove(struct platform_de { struct ssc_device *ssc = platform_get_drvdata(pdev); - spin_lock(&user_lock); + mutex_lock(&user_lock); list_del(&ssc->list); - spin_unlock(&user_lock); + mutex_unlock(&user_lock); return 0; }