From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dirk Behme Subject: Re: linux-next: Crash in arm_pmu_device_probe() due to 'drivers/perf: arm_pmu: make info messages more verbose' Date: Fri, 18 Mar 2016 10:18:36 +0100 Message-ID: <56EBC7EC.6000907@de.bosch.com> References: <56EBA3C3.10907@roeck-us.net> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from smtp6-v.fe.bosch.de ([139.15.237.11]:38208 "EHLO smtp6-v.fe.bosch.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754122AbcCRJSk (ORCPT ); Fri, 18 Mar 2016 05:18:40 -0400 In-Reply-To: <56EBA3C3.10907@roeck-us.net> Sender: linux-next-owner@vger.kernel.org List-ID: To: Guenter Roeck Cc: "linux-kernel@vger.kernel.org" , "linux-next@vger.kernel.org" , Will Deacon Hi Guenter, On 18.03.2016 07:44, Guenter Roeck wrote: > Hi, > > I am seeing the attached crash when running a realview-pb-a8 image with > realview_defconfig in qemu. > bisect wasn't successful, but a commit analysis identified commit > 'drivers/perf: arm_pmu: make info > messages more verbose' as the culprit. Reverting this commit fixes the > problem. > > The code roughly looks as follows. > > int arm_pmu_device_probe() > { > ... > if (node && ..) { > } else { > } > > if (ret) { > pr_info("%s: failed to probe PMU! Error %i\n", > node->full_name, ret); > goto out_free; > } > .... > out_free: > pr_info("%s: failed to register PMU devices! Error %i\n", > node->full_name, ret); > .... > } > > Note that 'node' is dereferenced even though it was previously checked > if it is NULL. > The configuration I am testing does not use devicetree. > > Can you use dev_info() instead ? Does anything like below [1] does work for you? If so, could you please share the output? I.e. what it prints in your non-devicetree non-pmu case? Best regards Dirk [1] diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c index 11bacc7..bda3502 100644 --- a/drivers/perf/arm_pmu.c +++ b/drivers/perf/arm_pmu.c @@ -1002,8 +1002,7 @@ int arm_pmu_device_probe(struct platform_device *pdev, } if (ret) { - pr_info("%s: failed to probe PMU! Error %i\n", - node->full_name, ret); + dev_info(&pdev->dev, "failed to probe PMU! Error %i\n", ret); goto out_free; } @@ -1023,8 +1022,7 @@ int arm_pmu_device_probe(struct platform_device *pdev, out_destroy: cpu_pmu_destroy(pmu); out_free: - pr_info("%s: failed to register PMU devices! Error %i\n", - node->full_name, ret); + dev_info(&pdev->dev, "failed to register PMU devices! Error %i\n", ret); kfree(pmu); return ret; }