From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F0ABDEB64DD for ; Fri, 11 Aug 2023 08:39:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233175AbjHKIjx (ORCPT ); Fri, 11 Aug 2023 04:39:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48848 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229793AbjHKIjw (ORCPT ); Fri, 11 Aug 2023 04:39:52 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 6B72B2737 for ; Fri, 11 Aug 2023 01:39:51 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 61C08D75; Fri, 11 Aug 2023 01:40:33 -0700 (PDT) Received: from [192.168.1.3] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 116763F59C; Fri, 11 Aug 2023 01:39:49 -0700 (PDT) Message-ID: <07b0dabb-5409-9ba8-543f-aeecafe083e9@arm.com> Date: Fri, 11 Aug 2023 09:39:40 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.9.0 Subject: Re: [PATCH] coresight: etm4x: Ensure valid drvdata and clock before clk_put() To: Anshuman Khandual , linux-arm-kernel@lists.infradead.org, suzuki.poulose@arm.com Cc: Mike Leach , coresight@lists.linaro.org, linux-kernel@vger.kernel.org, Dan Carpenter References: <20230811062738.1066787-1-anshuman.khandual@arm.com> Content-Language: en-US From: James Clark In-Reply-To: <20230811062738.1066787-1-anshuman.khandual@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/08/2023 07:27, Anshuman Khandual wrote: > This validates 'drvdata' and 'drvdata->pclk' clock before calling clk_put() > in etm4_remove_platform_dev(). The problem was detected using Smatch static > checker as reported. > > Cc: Suzuki K Poulose > Cc: Mike Leach > Cc: James Clark > Cc: coresight@lists.linaro.org > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > Reported-by: Dan Carpenter > Closes: https://lists.linaro.org/archives/list/coresight@lists.linaro.org/thread/G4N6P4OXELPLLQSNU3GU2MR4LOLRXRMJ/ > Signed-off-by: Anshuman Khandual > --- > This applies on coresight-next > > drivers/hwtracing/coresight/coresight-etm4x-core.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c > index 703b6fcbb6a5..eb412ce302cc 100644 > --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c > +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c > @@ -2269,7 +2269,7 @@ static int __exit etm4_remove_platform_dev(struct platform_device *pdev) > etm4_remove_dev(drvdata); > pm_runtime_disable(&pdev->dev); > > - if (drvdata->pclk) > + if (drvdata && drvdata->pclk && !IS_ERR(drvdata->pclk)) > clk_put(drvdata->pclk); > > return 0; It could be !IS_ERR_OR_NULL(drvdata->pclk), but I wouldn't bother changing it at this point. Reviewed-by: James Clark