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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 D25B0C4CEC9 for ; Fri, 20 Sep 2019 14:37:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A8AD620C01 for ; Fri, 20 Sep 2019 14:37:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391900AbfITOgT (ORCPT ); Fri, 20 Sep 2019 10:36:19 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:35836 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388055AbfITOZB (ORCPT ); Fri, 20 Sep 2019 10:25:01 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1iBJqD-0004xC-Vu; Fri, 20 Sep 2019 15:24:58 +0100 Received: from ben by deadeye with local (Exim 4.92.1) (envelope-from ) id 1iBJqD-0007rD-2D; Fri, 20 Sep 2019 15:24:57 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Guenter Roeck" Date: Fri, 20 Sep 2019 15:23:35 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 033/132] hwmon: (vt1211) Use request_muxed_region for Super-IO accesses In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 3.16.74-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Guenter Roeck commit 14b97ba5c20056102b3dd22696bf17b057e60976 upstream. 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: 2219cd81a6cd ("hwmon/vt1211: Add probing of alternate config index port") Signed-off-by: Guenter Roeck Signed-off-by: Ben Hutchings --- drivers/hwmon/vt1211.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) --- a/drivers/hwmon/vt1211.c +++ b/drivers/hwmon/vt1211.c @@ -226,15 +226,21 @@ static inline void superio_select(int si outb(ldn, sio_cip + 1); } -static inline void superio_enter(int sio_cip) +static inline int superio_enter(int sio_cip) { + if (!request_muxed_region(sio_cip, 2, DRVNAME)) + return -EBUSY; + outb(0x87, sio_cip); outb(0x87, sio_cip); + + return 0; } static inline void superio_exit(int sio_cip) { outb(0xaa, sio_cip); + release_region(sio_cip, 2); } /* --------------------------------------------------------------------- @@ -1280,11 +1286,14 @@ EXIT: static int __init vt1211_find(int sio_cip, unsigned short *address) { - int err = -ENODEV; + int err; int devid; - superio_enter(sio_cip); + err = superio_enter(sio_cip); + if (err) + return err; + err = -ENODEV; devid = force_id ? force_id : superio_inb(sio_cip, SIO_VT1211_DEVID); if (devid != SIO_VT1211_ID) goto EXIT;