From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752862AbcFJJne (ORCPT ); Fri, 10 Jun 2016 05:43:34 -0400 Received: from mailout1.w1.samsung.com ([210.118.77.11]:45422 "EHLO mailout1.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752548AbcFJJn3 (ORCPT ); Fri, 10 Jun 2016 05:43:29 -0400 X-AuditID: cbfec7f5-f792a6d000001302-25-575a8bbee243 Subject: Re: [PATCH v4] power_supply: power_supply_read_temp only if use_cnt > 0 To: Rhyland Klein , Sebastian Reichel , Dmitry Eremin-Solenikov , David Woodhouse References: <1465507719-819-1-git-send-email-rklein@nvidia.com> Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Jon Hunter , stable@vger.kernel.org From: Krzysztof Kozlowski Message-id: <575A8BBC.7040306@samsung.com> Date: Fri, 10 Jun 2016 11:43:24 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.8.0 MIME-version: 1.0 In-reply-to: <1465507719-819-1-git-send-email-rklein@nvidia.com> Content-type: text/plain; charset=windows-1252 Content-transfer-encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrKLMWRmVeSWpSXmKPExsVy+t/xq7r7uqPCDb7+Z7GY9OQ9s8XElZOZ LVpmLWKxeP3C0OLyrjlsFp97jzBaLDu+mtXi9O4SiwUbHzE6cHrsnHWX3WPzCi2PTas62Tx6 m9+xefRtWcXo8XmTXABbFJdNSmpOZllqkb5dAlfGwt2tTAUXRSp6zy1gbmD8KdDFyMEhIWAi caqJs4uRE8gUk7hwbz0biC0ksJRRYv9R9S5GLiD7GaPElRvbmEESwgIBEhcOfmUGSYgILGGU +LmjkRGiw15izqO1YN3MAuUSd863sYDYbALGEpuXLwGL8wpoSby5OBvMZhFQlfi9YDKYLSoQ ITFr+w8miBpBiR+T74H1cgo4SMy7uosF5FBmAT2J+xe1IMbLS2xe85Z5AqPALCQdsxCqZiGp WsDIvIpRNLU0uaA4KT3XSK84Mbe4NC9dLzk/dxMjJPC/7mBceszqEKMAB6MSD2/ErshwIdbE suLK3EOMEhzMSiK8jzuiwoV4UxIrq1KL8uOLSnNSiw8xSnOwKInzztz1PkRIID2xJDU7NbUg tQgmy8TBKdXAeGpHvce772uNXP1lfxod8A878lxgKt9UncvTd5w6OlX9nswJtrUCz95N/8Oe wpv6mZF94/FVvjmfLjDe1b2x1orL//08xw1lvQmZs6xrxOL3vq1dr8R3fVeexjf+/tMz6/4/ 9C//cC/Nc6v05YCZhfp5P5JnXuAzP7l8U4/87Z2hf+Kjz96bu0SJpTgj0VCLuag4EQAwEjHC eAIAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/09/2016 11:28 PM, Rhyland Klein wrote: > 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") > Cc: stable@vger.kernel.org > Signed-off-by: Rhyland Klein > --- > v4: > - Fixed return check conditions > - Removed change to power_supply_get_property return code > - removed whitespace change > > v3: > - Changed calls to ->get_property() to use common > power_supply_get_property() > - reworded description, added "Fixes" line > - Changed return value of power_supply_get_property() to -EAGAIN > > v2: > - Added cc stable > - changed return to -EAGAIN in case of use_cnt < 1 > - Removed WARNING > - return value check added in additional patch: > https://patchwork.kernel.org/patch/9158805/ > > drivers/power/power_supply_core.c | 27 ++++++++++++++++----------- > 1 file changed, 16 insertions(+), 11 deletions(-) Looks okay: Reviewed-by: Krzysztof Kozlowski Best regards, Krzysztof