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 X-Spam-Level: X-Spam-Status: No, score=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A815DC43460 for ; Wed, 7 Apr 2021 15:56:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8188461132 for ; Wed, 7 Apr 2021 15:56:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232798AbhDGP4Q (ORCPT ); Wed, 7 Apr 2021 11:56:16 -0400 Received: from foss.arm.com ([217.140.110.172]:59716 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347463AbhDGP4N (ORCPT ); Wed, 7 Apr 2021 11:56:13 -0400 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 1A4A61063; Wed, 7 Apr 2021 08:56:04 -0700 (PDT) Received: from [10.57.26.91] (unknown [10.57.26.91]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E88DF3F694; Wed, 7 Apr 2021 08:56:02 -0700 (PDT) Subject: Re: [PATCH] memory: samsung: exynos5422-dmc: handle clk_set_parent() failure To: Krzysztof Kozlowski References: <20210407154535.70756-1-krzysztof.kozlowski@canonical.com> From: Lukasz Luba Cc: linux-pm@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Message-ID: <1906533a-e86a-10fe-5bc3-4600af98d579@arm.com> Date: Wed, 7 Apr 2021 16:56:00 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <20210407154535.70756-1-krzysztof.kozlowski@canonical.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Krzysztof, On 4/7/21 4:45 PM, Krzysztof Kozlowski wrote: > clk_set_parent() can fail and ignoring such case could lead to invalid > clock setup for given frequency. > > Addresses-Coverity: Unchecked return value > Fixes: 6e7674c3c6df ("memory: Add DMC driver for Exynos5422") > Signed-off-by: Krzysztof Kozlowski > --- > drivers/memory/samsung/exynos5422-dmc.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/memory/samsung/exynos5422-dmc.c b/drivers/memory/samsung/exynos5422-dmc.c > index 56f6e65d40cd..9c8318923ed0 100644 > --- a/drivers/memory/samsung/exynos5422-dmc.c > +++ b/drivers/memory/samsung/exynos5422-dmc.c > @@ -1293,7 +1293,9 @@ static int exynos5_dmc_init_clks(struct exynos5_dmc *dmc) > > dmc->curr_volt = target_volt; > > - clk_set_parent(dmc->mout_mx_mspll_ccore, dmc->mout_spll); > + ret = clk_set_parent(dmc->mout_mx_mspll_ccore, dmc->mout_spll); > + if (ret) > + return ret; > > clk_prepare_enable(dmc->fout_bpll); > clk_prepare_enable(dmc->mout_bpll); > Thanks for running these tests and for the patch. I've checked how many many places this function is used in the kernel and return is ignored - in a lot of places... This patch LGTM. Reviewed-by: Lukasz Luba Regards, Lukasz