Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755940AbbBPQPX (ORCPT ); Mon, 16 Feb 2015 11:15:23 -0500 Received: from mail-ie0-f175.google.com ([209.85.223.175]:43876 "EHLO mail-ie0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753359AbbBPQPV (ORCPT ); Mon, 16 Feb 2015 11:15:21 -0500 MIME-Version: 1.0 Reply-To: cw00.choi@samsung.com In-Reply-To: <20150216160633.29eac148@amdc2363> References: <1424096414-4327-1-git-send-email-cw00.choi@samsung.com> <1424096414-4327-2-git-send-email-cw00.choi@samsung.com> <20150216160633.29eac148@amdc2363> Date: Tue, 17 Feb 2015 01:15:20 +0900 Message-ID: Subject: Re: [PATCH 1/3] thermal: exynos: Fix NULL pointer exception during kernel booting From: Chanwoo Choi To: Lukasz Majewski Cc: Zhang Rui , Eduardo Valentin , Kukjin Kim , Bartlomiej Zolnierkiewicz , Kyungmin Park , Amit Kachhap , Abhilash Kesavan , "inki.dae@samsung.com" , "linux-pm@vger.kernel.org" , linux-arm-kernel , linux-samsung-soc , linux-kernel Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1814 Lines: 49 Hi Lukasz, On Tue, Feb 17, 2015 at 12:06 AM, Lukasz Majewski wrote: > Hi Chanwoo, > >> This patch fixes the NULL pointer exception during kernel booting. >> The thermal_zone _of_sensor_register() registers a sensor to DT >> thermal zone and then read the current temperature by '.get_temp' >> callback. The callback function of exynos thermal driver is >> exynos_get_temp() which must need the 'pdata' instance of exynos_tmu >> _platform_data structure. >> - exynos_get_temp() -> code_to_temp() -> Must need the 'pdata' >> instance >> >> But, exynos thermal driver is executed before getting the 'pdata' >> instance. To avoid the kernel panic, have to get the platform data by >> executing the exynos_map_dt_data() before calling >> thermal_zone_of_sensor_register() . > > I've already prepared patch for this (unfortunately it isn't yet > applied to mainline): > > "[PATCH] thermal: exynos: fix: Check if data->tmu_read callback is > present before read" > > http://www.spinics.net/lists/linux-samsung-soc/msg42245.html There is different issue between you patch and this patch. Your patch check the whether data->tmu_read is NULL or not. But, my patch check the pdata is NULL or not. > > Does applying this patch help? > > BTW: How can I reproduce this error? Could you point me the SHA1 and > repository? I used your patch-set of linux-soc-thermal.git (branch: next). So I applied you patchiest on Linux 3.19 for test. - https://git.kernel.org/cgit/linux/kernel/git/evalenti/linux-soc-thermal.git/log/?h=next Best Regards, Chanwoo Choi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/