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=-9.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH,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 692D7C28EBD for ; Sun, 9 Jun 2019 17:01:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4357620833 for ; Sun, 9 Jun 2019 17:01:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560099706; bh=Ss3/1aNf6BV0NDPMl7bx6++BVlpIDWzqubpvj80s7W0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=rVOdRmp+3rP6d30CxKauKpY4QHFBWDzdBiOGF0QknFLAKpjBNMn5Xs3JFaQ4nFXmn 2jVwhuxhNfCpfhM1EJaKMYCXEJNuPSKvgPdBZQ6WVFtXxSsTHZadNxi6apkpW+O51v +/LIjzCIekOCxDwxba4PWoOIP4v0/6dGp1o7C2UQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388127AbfFIRBp (ORCPT ); Sun, 9 Jun 2019 13:01:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:39140 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388107AbfFIRBm (ORCPT ); Sun, 9 Jun 2019 13:01:42 -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 564D2206DF; Sun, 9 Jun 2019 17:01:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560099701; bh=Ss3/1aNf6BV0NDPMl7bx6++BVlpIDWzqubpvj80s7W0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kKpqk4r6DXF6dhqOic2eBrHOmhTrI+lAtN8fTcW5PIad/2oF3hIg/9AEjJKkZL1gD wEpZCmrGGCL9i9ac9zCdPLzzr3+gDYDOEVR6Ti+Y9dl2J3oCmw84A73WUHWr+DL62S gHFRilLnWzmTmXrZs6QAbOu06g2fX8GCvGJdioIY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kefeng Wang , John Garry , Guenter Roeck , Sasha Levin Subject: [PATCH 4.4 133/241] hwmon: (smsc47m1) Use request_muxed_region for Super-IO accesses Date: Sun, 9 Jun 2019 18:41:15 +0200 Message-Id: <20190609164151.635341098@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190609164147.729157653@linuxfoundation.org> References: <20190609164147.729157653@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 [ Upstream commit d6410408ad2a798c4cc685252c1baa713be0ad69 ] Super-IO accesses may fail on a system with no or unmapped LPC bus. Also, other drivers may attempt to access the LPC bus at the same time, resulting in undefined behavior. Use request_muxed_region() to ensure that IO access on the requested address space is supported, and to ensure that access by multiple drivers is synchronized. Fixes: 8d5d45fb1468 ("I2C: Move hwmon drivers (2/3)") Reported-by: Kefeng Wang Reported-by: John Garry Cc: John Garry Acked-by: John Garry Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/smsc47m1.c | 28 +++++++++++++++++++--------- 1 file changed, 19 insertions(+), 9 deletions(-) diff --git a/drivers/hwmon/smsc47m1.c b/drivers/hwmon/smsc47m1.c index 5d323186d2c10..d24df0c50bea4 100644 --- a/drivers/hwmon/smsc47m1.c +++ b/drivers/hwmon/smsc47m1.c @@ -73,16 +73,21 @@ superio_inb(int reg) /* logical device for fans is 0x0A */ #define superio_select() superio_outb(0x07, 0x0A) -static inline void +static inline int superio_enter(void) { + if (!request_muxed_region(REG, 2, DRVNAME)) + return -EBUSY; + outb(0x55, REG); + return 0; } static inline void superio_exit(void) { outb(0xAA, REG); + release_region(REG, 2); } #define SUPERIO_REG_ACT 0x30 @@ -531,8 +536,12 @@ static int __init smsc47m1_find(struct smsc47m1_sio_data *sio_data) { u8 val; unsigned short addr; + int err; + + err = superio_enter(); + if (err) + return err; - superio_enter(); val = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID); /* @@ -608,13 +617,14 @@ static int __init smsc47m1_find(struct smsc47m1_sio_data *sio_data) static void smsc47m1_restore(const struct smsc47m1_sio_data *sio_data) { if ((sio_data->activate & 0x01) == 0) { - superio_enter(); - superio_select(); - - pr_info("Disabling device\n"); - superio_outb(SUPERIO_REG_ACT, sio_data->activate); - - superio_exit(); + if (!superio_enter()) { + superio_select(); + pr_info("Disabling device\n"); + superio_outb(SUPERIO_REG_ACT, sio_data->activate); + superio_exit(); + } else { + pr_warn("Failed to disable device\n"); + } } } -- 2.20.1