From patchwork Mon Jun 6 16:55:40 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rhyland Klein X-Patchwork-Id: 9158807 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 3449B60759 for ; Mon, 6 Jun 2016 16:57:23 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 233F32833E for ; Mon, 6 Jun 2016 16:57:23 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 157182834C; Mon, 6 Jun 2016 16:57:23 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 62AF82833E for ; Mon, 6 Jun 2016 16:57:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751208AbcFFQ5V (ORCPT ); Mon, 6 Jun 2016 12:57:21 -0400 Received: from hqemgate15.nvidia.com ([216.228.121.64]:14910 "EHLO hqemgate15.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751120AbcFFQ5U (ORCPT ); Mon, 6 Jun 2016 12:57:20 -0400 Received: from hqnvupgp08.nvidia.com (Not Verified[216.228.121.13]) by hqemgate15.nvidia.com id ; Mon, 06 Jun 2016 09:57:09 -0700 Received: from HQMAIL108.nvidia.com ([172.18.146.13]) by hqnvupgp08.nvidia.com (PGP Universal service); Mon, 06 Jun 2016 09:55:00 -0700 X-PGP-Universal: processed; by hqnvupgp08.nvidia.com on Mon, 06 Jun 2016 09:55:00 -0700 Received: from HQMAIL112.nvidia.com (172.18.146.18) by HQMAIL108.nvidia.com (172.18.146.13) with Microsoft SMTP Server (TLS) id 15.0.1130.7; Mon, 6 Jun 2016 16:57:13 +0000 Received: from HQMAIL106.nvidia.com (172.18.146.12) by HQMAIL112.nvidia.com (172.18.146.18) with Microsoft SMTP Server (TLS) id 15.0.1130.7; Mon, 6 Jun 2016 16:57:13 +0000 Received: from hqnvemgw02.nvidia.com (172.16.227.111) by HQMAIL106.nvidia.com (172.18.146.12) with Microsoft SMTP Server id 15.0.1130.7 via Frontend Transport; Mon, 6 Jun 2016 16:57:13 +0000 Received: from rklein-work.nvidia.com (Not Verified[10.2.68.50]) by hqnvemgw02.nvidia.com with Trustwave SEG (v7, 5, 5, 8150) id ; Mon, 06 Jun 2016 09:57:12 -0700 From: Rhyland Klein To: Sebastian Reichel , Dmitry Eremin-Solenikov , David Woodhouse CC: , , Jon Hunter , Krzysztof Kozlowski , Rhyland Klein , Subject: [PATCH] power_supply: power_supply_read_temp only if use_cnt > 0 Date: Mon, 6 Jun 2016 12:55:40 -0400 Message-ID: <1465232140-12530-1-git-send-email-rklein@nvidia.com> X-Mailer: git-send-email 1.9.1 X-NVConfidentiality: public MIME-Version: 1.0 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add check to power_supply_read_temp() to only use the power_supply get_property() callback if the use_cnt is > 0. The use_cnt will be incremented at the end of __power_supply_register, so this will block to case where get_property can be called before the supply is fully registered. This fixes the issue show in the stack below: [ 1.452598] power_supply_read_temp+0x78/0x80 [ 1.458680] thermal_zone_get_temp+0x5c/0x11c [ 1.464765] thermal_zone_device_update+0x34/0xb4 [ 1.471195] thermal_zone_device_register+0x87c/0x8cc [ 1.477974] __power_supply_register+0x364/0x424 [ 1.484317] power_supply_register_no_ws+0x10/0x18 [ 1.490833] bq27xxx_battery_setup+0x10c/0x164 [ 1.497003] bq27xxx_battery_i2c_probe+0xd0/0x1b0 [ 1.503435] i2c_device_probe+0x174/0x240 [ 1.509172] driver_probe_device+0x1fc/0x29c [ 1.515167] __driver_attach+0xa4/0xa8 [ 1.520643] bus_for_each_dev+0x58/0x98 [ 1.526204] driver_attach+0x20/0x28 [ 1.531505] bus_add_driver+0x1c8/0x22c [ 1.537067] driver_register+0x68/0x108 [ 1.542630] i2c_register_driver+0x38/0x7c [ 1.548457] bq27xxx_battery_i2c_driver_init+0x18/0x20 [ 1.555321] do_one_initcall+0x38/0x12c [ 1.560886] kernel_init_freeable+0x148/0x1ec [ 1.566972] kernel_init+0x10/0xfc [ 1.572101] ret_from_fork+0x10/0x40 Cc: stable@vger.kernel.org Signed-off-by: Rhyland Klein --- v2: - Added cc stable - changed return to -EAGAIN in case of use_cnt < 1 - Removed WARNING - return value check added in additional patch: "thermal: helpers: Check return value of get_temp" drivers/power/power_supply_core.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/power/power_supply_core.c b/drivers/power/power_supply_core.c index 456987c88baa..bbd80631f31e 100644 --- a/drivers/power/power_supply_core.c +++ b/drivers/power/power_supply_core.c @@ -561,11 +561,15 @@ static int power_supply_read_temp(struct thermal_zone_device *tzd, { struct power_supply *psy; union power_supply_propval val; - int ret; + int ret = -EAGAIN; WARN_ON(tzd == NULL); + psy = tzd->devdata; - ret = psy->desc->get_property(psy, POWER_SUPPLY_PROP_TEMP, &val); + + if (atomic_read(&psy->use_cnt) > 0) + ret = psy->desc->get_property(psy, POWER_SUPPLY_PROP_TEMP, + &val); /* Convert tenths of degree Celsius to milli degree Celsius. */ if (!ret)