From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932403AbcHHTSq (ORCPT ); Mon, 8 Aug 2016 15:18:46 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:36602 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753309AbcHHTSl (ORCPT ); Mon, 8 Aug 2016 15:18:41 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Rhyland Klein , Krzysztof Kozlowski , Sebastian Reichel Subject: [PATCH 4.6 51/96] power_supply: power_supply_read_temp only if use_cnt > 0 Date: Mon, 8 Aug 2016 21:11:14 +0200 Message-Id: <20160808180246.129081461@linuxfoundation.org> X-Mailer: git-send-email 2.9.2 In-Reply-To: <20160808180243.898163389@linuxfoundation.org> References: <20160808180243.898163389@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Rhyland Klein commit 5bc28b93a36e3cb3acc2870fb75cb6ffb182fece upstream. Change power_supply_read_temp() to use power_supply_get_property() so that it will check the use_cnt and ensure it 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 Also make the same change to ps_get_max_charge_cntl_limit() and ps_get_cur_chrage_cntl_limit() to be safe. Lastly, change the return value of power_supply_get_property() to -EAGAIN from -ENODEV if use_cnt <= 0. Fixes: 297d716f6260 ("power_supply: Change ownership from driver to core") Signed-off-by: Rhyland Klein Reviewed-by: Krzysztof Kozlowski Signed-off-by: Sebastian Reichel Signed-off-by: Greg Kroah-Hartman --- drivers/power/power_supply_core.c | 27 ++++++++++++++++----------- 1 file changed, 16 insertions(+), 11 deletions(-) --- a/drivers/power/power_supply_core.c +++ b/drivers/power/power_supply_core.c @@ -565,11 +565,12 @@ static int power_supply_read_temp(struct WARN_ON(tzd == NULL); psy = tzd->devdata; - ret = psy->desc->get_property(psy, POWER_SUPPLY_PROP_TEMP, &val); + ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_TEMP, &val); + if (ret) + return ret; /* Convert tenths of degree Celsius to milli degree Celsius. */ - if (!ret) - *temp = val.intval * 100; + *temp = val.intval * 100; return ret; } @@ -612,10 +613,12 @@ static int ps_get_max_charge_cntl_limit( int ret; psy = tcd->devdata; - ret = psy->desc->get_property(psy, - POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX, &val); - if (!ret) - *state = val.intval; + ret = power_supply_get_property(psy, + POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX, &val); + if (ret) + return ret; + + *state = val.intval; return ret; } @@ -628,10 +631,12 @@ static int ps_get_cur_chrage_cntl_limit( int ret; psy = tcd->devdata; - ret = psy->desc->get_property(psy, - POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val); - if (!ret) - *state = val.intval; + ret = power_supply_get_property(psy, + POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val); + if (ret) + return ret; + + *state = val.intval; return ret; }