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=-13.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 4701FC43460 for ; Thu, 29 Apr 2021 06:49:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0072761446 for ; Thu, 29 Apr 2021 06:48:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239073AbhD2Gto (ORCPT ); Thu, 29 Apr 2021 02:49:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238748AbhD2Gtm (ORCPT ); Thu, 29 Apr 2021 02:49:42 -0400 Received: from mail-wr1-x42a.google.com (mail-wr1-x42a.google.com [IPv6:2a00:1450:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AD0D7C06138C for ; Wed, 28 Apr 2021 23:48:56 -0700 (PDT) Received: by mail-wr1-x42a.google.com with SMTP id h15so13341117wre.11 for ; Wed, 28 Apr 2021 23:48:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:in-reply-to:references:date:message-id :mime-version; bh=o3h5EriEjCqQopiIHnHAtghPtkLJbZARkrJvdBbmedE=; b=d8dCRC4gjEhWMxE3SYQi+NpLceGRBYrmrFpjvbmsHAWECYSzCFyO0o/bHyEnKk1lfa SgH7w9204VdW7XjaaZXmFjJk4bd/euAM+GpLQUin9KJiQSCAbgM4UJHe9Jo1hZvD7Klm RJnAWx/25XGVuxr2RREacpJRN432K6oHtarC/d+DneSuNnDp/uVuZ3pX357f0+OOsQK1 EXtn41+WlXzp6ZWT7FF+1ohfUOnZCL+5eVO6E25kevnK4FdNzf7XMJC3mUnicrdevtOF srDScOmKoiKziGoBM/B1eEA8dxqYx1e4pTmZw0J7VPu7zatqfsqnpcXThHz1bwX3Qn1v vZ3w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=o3h5EriEjCqQopiIHnHAtghPtkLJbZARkrJvdBbmedE=; b=MG7/tZrzxSJzGQgEslMSrkTkW9Gr59LihThtloa2i1+FRuQKIWpTQ9ggnL/Nec+gEN HDt3qij3vDzTxtSO4cZ5vZSIP/sY5d6QPwqFR07IF0OweHBtlrcQIQ7FtN95/+Q6Ey1x hIVc2hD4ubGYlPDiwRMjjaPLhGB5pV+t4c69K3aTYm4Y9Z4VlcyqzXDPQ7CFe9qCZKqO nTexQBlDP6yk1snhdxxnJvhx9vOS+fpa8lgSApm/UrCpVz+rkT/skNKn6/H687fesVT9 HvRgdbANxut2rVuvmIhPTLV5bFqzEuVzvi0t9vtqqYX1RfB5H30/ml4wxyA2euq2XP+t UEBA== X-Gm-Message-State: AOAM531ZiMfuxeJmkeWltnUvbu/qv2ISACQ3OaIW07m3ZnLFD0Cji+LF DVoPBo/iwbtomibQr73C4/K2rQ== X-Google-Smtp-Source: ABdhPJyQ18dyuVmmPQJLNTxgisV36R9DWwMSNPYNEPe4j4InyGwlgS2BBW/xtr/CvurtASHAvnQZsQ== X-Received: by 2002:adf:f74d:: with SMTP id z13mr817646wrp.147.1619678935368; Wed, 28 Apr 2021 23:48:55 -0700 (PDT) Received: from localhost ([2a01:cb19:826e:8e00:f37e:9091:b397:6f48]) by smtp.gmail.com with ESMTPSA id z18sm3264416wrh.16.2021.04.28.23.48.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 28 Apr 2021 23:48:54 -0700 (PDT) From: Mattijs Korpershoek To: Dmitry Torokhov Cc: Matthias Brugger , fparent@baylibre.com, linux-input@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/7] Input: mtk-pmic-keys - check for NULL on of_match_device() In-Reply-To: References: <20210428164219.1115537-1-mkorpershoek@baylibre.com> <20210428164219.1115537-2-mkorpershoek@baylibre.com> Date: Thu, 29 Apr 2021 08:48:53 +0200 Message-ID: <875z05y4a2.fsf@baylibre.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Dmitry, Dmitry Torokhov writes: > Hi Mattijs, > > On Wed, Apr 28, 2021 at 06:42:13PM +0200, Mattijs Korpershoek wrote: >> mtk-pmic-keys being a child device of mt6397, it will always get probed >> when mt6397_probe() is called. >> >> This also happens when we have no device tree node matching >> mediatek,mt6397-keys. > > It sounds for me that creating a platform device instance in case where > we know need OF node, but do not have one, is wasteful. Can > mt6397-core.c and/or MFD core be adjusted to not do that. You are right. Maybe I can fix MFD core instead. I will look into it. Thanks for your review. > >> >> In that case, the mfd core warns us: >> >> [ 0.352175] mtk-pmic-keys: Failed to locate of_node [id: -1] >> >> Check return value from call to of_match_device() >> in order to prevent a NULL pointer dereference. >> >> In case of NULL print error message and return -ENODEV >> >> Signed-off-by: Mattijs Korpershoek >> --- >> drivers/input/keyboard/mtk-pmic-keys.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/drivers/input/keyboard/mtk-pmic-keys.c b/drivers/input/keyboard/mtk-pmic-keys.c >> index 62391d6c7da6..12c449eed026 100644 >> --- a/drivers/input/keyboard/mtk-pmic-keys.c >> +++ b/drivers/input/keyboard/mtk-pmic-keys.c >> @@ -247,6 +247,9 @@ static int mtk_pmic_keys_probe(struct platform_device *pdev) >> const struct of_device_id *of_id = >> of_match_device(of_mtk_pmic_keys_match_tbl, &pdev->dev); >> >> + if (!of_id) >> + return -ENODEV; >> + > > So if we make MFD/6396 core smarter we would not be needing this. I > guess there is still a possibility of someone stuffing "mtk-pmic-keys" > into "driver_override" attribute of a random platform device but I > wonder if we really need to take care of such scenarios... > >> keys = devm_kzalloc(&pdev->dev, sizeof(*keys), GFP_KERNEL); >> if (!keys) >> return -ENOMEM; >> -- >> 2.27.0 >> > > Thanks. > > -- > Dmitry 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=-14.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 879C4C433B4 for ; Thu, 29 Apr 2021 06:49:29 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 49E1D61447 for ; 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Wed, 28 Apr 2021 23:48:54 -0700 (PDT) From: Mattijs Korpershoek To: Dmitry Torokhov Cc: Matthias Brugger , fparent@baylibre.com, linux-input@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/7] Input: mtk-pmic-keys - check for NULL on of_match_device() In-Reply-To: References: <20210428164219.1115537-1-mkorpershoek@baylibre.com> <20210428164219.1115537-2-mkorpershoek@baylibre.com> Date: Thu, 29 Apr 2021 08:48:53 +0200 Message-ID: <875z05y4a2.fsf@baylibre.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210428_234910_665807_A99342E6 X-CRM114-Status: GOOD ( 23.40 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org Hi Dmitry, Dmitry Torokhov writes: > Hi Mattijs, > > On Wed, Apr 28, 2021 at 06:42:13PM +0200, Mattijs Korpershoek wrote: >> mtk-pmic-keys being a child device of mt6397, it will always get probed >> when mt6397_probe() is called. >> >> This also happens when we have no device tree node matching >> mediatek,mt6397-keys. > > It sounds for me that creating a platform device instance in case where > we know need OF node, but do not have one, is wasteful. Can > mt6397-core.c and/or MFD core be adjusted to not do that. You are right. Maybe I can fix MFD core instead. I will look into it. Thanks for your review. > >> >> In that case, the mfd core warns us: >> >> [ 0.352175] mtk-pmic-keys: Failed to locate of_node [id: -1] >> >> Check return value from call to of_match_device() >> in order to prevent a NULL pointer dereference. >> >> In case of NULL print error message and return -ENODEV >> >> Signed-off-by: Mattijs Korpershoek >> --- >> drivers/input/keyboard/mtk-pmic-keys.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/drivers/input/keyboard/mtk-pmic-keys.c b/drivers/input/keyboard/mtk-pmic-keys.c >> index 62391d6c7da6..12c449eed026 100644 >> --- a/drivers/input/keyboard/mtk-pmic-keys.c >> +++ b/drivers/input/keyboard/mtk-pmic-keys.c >> @@ -247,6 +247,9 @@ static int mtk_pmic_keys_probe(struct platform_device *pdev) >> const struct of_device_id *of_id = >> of_match_device(of_mtk_pmic_keys_match_tbl, &pdev->dev); >> >> + if (!of_id) >> + return -ENODEV; >> + > > So if we make MFD/6396 core smarter we would not be needing this. I > guess there is still a possibility of someone stuffing "mtk-pmic-keys" > into "driver_override" attribute of a random platform device but I > wonder if we really need to take care of such scenarios... > >> keys = devm_kzalloc(&pdev->dev, sizeof(*keys), GFP_KERNEL); >> if (!keys) >> return -ENOMEM; >> -- >> 2.27.0 >> > > Thanks. > > -- > Dmitry _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek 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=-14.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 5EFAAC433ED for ; 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Wed, 28 Apr 2021 23:48:54 -0700 (PDT) From: Mattijs Korpershoek To: Dmitry Torokhov Cc: Matthias Brugger , fparent@baylibre.com, linux-input@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/7] Input: mtk-pmic-keys - check for NULL on of_match_device() In-Reply-To: References: <20210428164219.1115537-1-mkorpershoek@baylibre.com> <20210428164219.1115537-2-mkorpershoek@baylibre.com> Date: Thu, 29 Apr 2021 08:48:53 +0200 Message-ID: <875z05y4a2.fsf@baylibre.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210428_234910_121817_EAD63885 X-CRM114-Status: GOOD ( 24.70 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Dmitry, Dmitry Torokhov writes: > Hi Mattijs, > > On Wed, Apr 28, 2021 at 06:42:13PM +0200, Mattijs Korpershoek wrote: >> mtk-pmic-keys being a child device of mt6397, it will always get probed >> when mt6397_probe() is called. >> >> This also happens when we have no device tree node matching >> mediatek,mt6397-keys. > > It sounds for me that creating a platform device instance in case where > we know need OF node, but do not have one, is wasteful. Can > mt6397-core.c and/or MFD core be adjusted to not do that. You are right. Maybe I can fix MFD core instead. I will look into it. Thanks for your review. > >> >> In that case, the mfd core warns us: >> >> [ 0.352175] mtk-pmic-keys: Failed to locate of_node [id: -1] >> >> Check return value from call to of_match_device() >> in order to prevent a NULL pointer dereference. >> >> In case of NULL print error message and return -ENODEV >> >> Signed-off-by: Mattijs Korpershoek >> --- >> drivers/input/keyboard/mtk-pmic-keys.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/drivers/input/keyboard/mtk-pmic-keys.c b/drivers/input/keyboard/mtk-pmic-keys.c >> index 62391d6c7da6..12c449eed026 100644 >> --- a/drivers/input/keyboard/mtk-pmic-keys.c >> +++ b/drivers/input/keyboard/mtk-pmic-keys.c >> @@ -247,6 +247,9 @@ static int mtk_pmic_keys_probe(struct platform_device *pdev) >> const struct of_device_id *of_id = >> of_match_device(of_mtk_pmic_keys_match_tbl, &pdev->dev); >> >> + if (!of_id) >> + return -ENODEV; >> + > > So if we make MFD/6396 core smarter we would not be needing this. I > guess there is still a possibility of someone stuffing "mtk-pmic-keys" > into "driver_override" attribute of a random platform device but I > wonder if we really need to take care of such scenarios... > >> keys = devm_kzalloc(&pdev->dev, sizeof(*keys), GFP_KERNEL); >> if (!keys) >> return -ENOMEM; >> -- >> 2.27.0 >> > > Thanks. > > -- > Dmitry _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel