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=-7.0 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 autolearn=ham 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 5812BC28CC2 for ; Thu, 30 May 2019 06:45:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2217725AE2 for ; Thu, 30 May 2019 06:45:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=nokia.onmicrosoft.com header.i=@nokia.onmicrosoft.com header.b="ZieqnJ7Q" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727296AbfE3Gpv (ORCPT ); Thu, 30 May 2019 02:45:51 -0400 Received: from mail-eopbgr30090.outbound.protection.outlook.com ([40.107.3.90]:48386 "EHLO EUR03-AM5-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727273AbfE3Gpv (ORCPT ); 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received-spf: None (protection.outlook.com: nokia.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: TbQ5vX4AzRSFK3tDIkghpLR8bXo5eAxhoJneC/Yu73fgUyf8WV56c/jbNIIHj+HSHNa1mQkyKPXPVRb3+hOWJP4dWXptwUVE8m/gqRpi6VPTitSiGo8kDwakNtdpBQY2ADICB7dF0kdf6AQaN5m/ubUVVtUrcgkZrNlFmevEVmLFYsRyT/SplCOzLxgLBC8Hwb3tYypMNQyGQdHRFNsrlF82ZTlHmmK4CigSF7ELOf9xkN4750pSZUxCh0l8GBRe/mP1GOwKmQVAgICugHbX4cXqlhKWSOj56ZnJ/My3JC1Q7RJBJLOAmM1mc/XKJMHcuRPmeH/JhZ95PgoB4J8vTyCULtjuKXzJ3sazHjz3aGE96z60fjMHkpcuqRACOyCHeYJZ6IGjCTWsZGE9PtJegh5pCT4xGlWsBO0VX+4GC84= Content-Type: text/plain; charset="us-ascii" Content-ID: <51762DD8C076964D9B6394DE0B4DA36C@eurprd07.prod.outlook.com> Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: nokia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5bf69563-b5c6-4e45-8567-08d6e4ca72af X-MS-Exchange-CrossTenant-originalarrivaltime: 30 May 2019 06:45:48.1134 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 5d471751-9675-428d-917b-70f44f9630b0 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: krzysztof.adamski@nokia.com X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB6PR07MB3368 Sender: linux-hwmon-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org The operation done in the pmbus_update_fan() function is a read-modify-write operation but it lacks any kind of lock protection which may cause problems if run more than once simultaneously. This patch uses an existing update_lock mutex to fix this problem. Signed-off-by: Krzysztof Adamski --- I'm resending this patch to proper recipients this time. Sorry if the previous submission confused anybody. drivers/hwmon/pmbus/pmbus_core.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_c= ore.c index ef7ee90ee785..94adbede7912 100644 --- a/drivers/hwmon/pmbus/pmbus_core.c +++ b/drivers/hwmon/pmbus/pmbus_core.c @@ -268,6 +268,7 @@ int pmbus_update_fan(struct i2c_client *client, int pag= e, int id, int rv; u8 to; =20 + mutex_lock(&data->update_lock); from =3D pmbus_read_byte_data(client, page, pmbus_fan_config_registers[id]); if (from < 0) @@ -278,11 +279,15 @@ int pmbus_update_fan(struct i2c_client *client, int p= age, int id, rv =3D pmbus_write_byte_data(client, page, pmbus_fan_config_registers[id], to); if (rv < 0) - return rv; + goto out; } =20 - return _pmbus_write_word_data(client, page, - pmbus_fan_command_registers[id], command); + rv =3D _pmbus_write_word_data(client, page, + pmbus_fan_command_registers[id], command); + +out: + mutex_lock(&data->update_lock); + return rv; } EXPORT_SYMBOL_GPL(pmbus_update_fan); =20 --=20 2.20.1