From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751390AbcBOTfA (ORCPT ); Mon, 15 Feb 2016 14:35:00 -0500 Received: from bh-25.webhostbox.net ([208.91.199.152]:54414 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751014AbcBOTe6 (ORCPT ); Mon, 15 Feb 2016 14:34:58 -0500 From: Guenter Roeck To: Viresh Kumar Cc: Nishanth Menon , Stephen Boyd , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Guenter Roeck , Viresh Kumar Subject: [PATCH -next] PM / OPP: Fix crash seen if CPU clock has no voltage regulator Date: Mon, 15 Feb 2016 11:34:53 -0800 Message-Id: <1455564893-25455-1-git-send-email-linux@roeck-us.net> X-Mailer: git-send-email 2.5.0 X-Authenticated_sender: guenter@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: guenter@roeck-us.net X-Authenticated-Sender: bh-25.webhostbox.net: guenter@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org omap3 overo boots crash with Unable to handle kernel NULL pointer dereference at virtual address 00000030 pgd = c0204000 [00000030] *pgd=00000000 Internal error: Oops: 17 [#1] SMP ARM ... [] (regulator_set_voltage) from [] (_set_opp_voltage+0x34/0x90) [] (_set_opp_voltage) from [] (dev_pm_opp_set_rate+0x19c/0x288) [] (dev_pm_opp_set_rate) from [] (__cpufreq_driver_target+0x17c/0x29c) [] (__cpufreq_driver_target) from [] (dbs_check_cpu+0x19c/0x1e4) [] (dbs_check_cpu) from [] (cpufreq_governor_dbs+0x308/0x5c4) [] (cpufreq_governor_dbs) from [] (__cpufreq_governor+0x20c/0x24c) [] (__cpufreq_governor) from [] (cpufreq_init_policy+0x60/0x8c) [] (cpufreq_init_policy) from [] (cpufreq_online+0x2cc/0x6d8) [] (cpufreq_online) from [] (subsys_interface_register+0x80/0xc4) [] (subsys_interface_register) from [] (cpufreq_register_driver+0x144/0x1a0) [] (cpufreq_register_driver) from [] (dt_cpufreq_probe+0x64/0xe8) [] (dt_cpufreq_probe) from [] (platform_drv_probe+0x50/0xb0) [] (platform_drv_probe) from [] (driver_probe_device+0x1f4/0x2b0) ... Analysis shows that regulator==NULL in regulator_set_voltage(). Code around _set_opp_voltage() suggests that having no voltage regulator attached to a CPU clock is valid, so do not attempt to set a voltage in that case. Fixes: 6a0712f6f199e ("PM / OPP: Add dev_pm_opp_set_rate()" Cc: Viresh Kumar Signed-off-by: Guenter Roeck --- drivers/base/power/opp/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index d7cd4e265766..82ad5ae72427 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -564,7 +564,7 @@ static int _set_opp_voltage(struct device *dev, struct regulator *reg, int ret; /* Regulator not available for device */ - if (IS_ERR(reg)) { + if (IS_ERR_OR_NULL(reg)) { dev_dbg(dev, "%s: regulator not available: %ld\n", __func__, PTR_ERR(reg)); return 0; -- 2.5.0