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=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 7F9A4C433ED for ; Wed, 28 Apr 2021 19:52:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 32BA661423 for ; Wed, 28 Apr 2021 19:52:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241730AbhD1Tx3 (ORCPT ); Wed, 28 Apr 2021 15:53:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49424 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232284AbhD1Tx1 (ORCPT ); Wed, 28 Apr 2021 15:53:27 -0400 Received: from mail-pf1-x42a.google.com (mail-pf1-x42a.google.com [IPv6:2607:f8b0:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2AB7DC061573; Wed, 28 Apr 2021 12:52:42 -0700 (PDT) Received: by mail-pf1-x42a.google.com with SMTP id v191so2695396pfc.8; Wed, 28 Apr 2021 12:52:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=/pKytGN9W8sMrVQvaOgwD5WVJi+L1fCKHCS1G7ffXOI=; b=JdOCV6VmnRIbLKx6LWiszLtHYvAkv+YliD1uLto2Y6DskP5feuZ1MAw4DS5RW+HFJ4 8zokwR1WHii0SuYzgFVWPHNRgWI2AhhKkMrVqbnzSEaj6wOzopLJEtFfaSPgjJw5s+n4 TqSWWAyy/KhkQhxPCVoRPlPl/7SgukqcyWd29bGs7Xqy+ieZDwu73MCwq3zdFz7Ptv4m em525mqmueFIEMONZbRdU4RmW47dKUG3CSlM58KGTgefI2jgeiuNd3EDF9xy+/XBg0Tn EHOVhT6zqINh0wW8wIEmpoX7xxxNP5C3fZngAkZfSz5954/GGsLV+kCtrhoV1hk/hYXc OM+g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=/pKytGN9W8sMrVQvaOgwD5WVJi+L1fCKHCS1G7ffXOI=; b=iRwcq2XtbfZiS7lIwkqlBiDKLOmGbTaAAhss5KVxEQSW2md5Lc8oT+ojJwfezvJpHN fHTkqyfptoKajnGPLZF5l2QGnjQYTmtY0ijxYBEZS8nGr9VG50TbIWPk2WzMjGTWxFZV Dkgoc3SFMVe4o/DxuMzSlCxfQ+bXzbIQtO/gUEX17B3Z0wsJf1dMDsenURN3TqgYApl7 kWVRwOrv+1pM0t/dC7DVav2VS2CLsW59QMcw6fnedc5sseSxzPGQwweQRi4ZQm59yCzU onH5x6W4y700XjkW3ap90baTrHEpzT3R3d1CBhFvxLXSBOv5h/DsUQ0L9UCRZf0DMMOy it6g== X-Gm-Message-State: AOAM531AIP47i09PUXxB88ftQ4pjPifA1YNGqxcb+ya0vgH5RzFYk4Lp MZduznvPasXN+7JHsu3M/Yg= X-Google-Smtp-Source: ABdhPJyR42PL2NF7XSqxdOxYCe5B8OyzbVldVe5KhSgU38V4lHZ6FgoTjWcNp+kqYN7WP3BqdhkR9w== X-Received: by 2002:a63:5d18:: with SMTP id r24mr29461665pgb.94.1619639561456; Wed, 28 Apr 2021 12:52:41 -0700 (PDT) Received: from google.com ([2620:15c:202:201:84c0:9bcd:2e20:f79d]) by smtp.gmail.com with ESMTPSA id 123sm430826pfz.127.2021.04.28.12.52.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 28 Apr 2021 12:52:40 -0700 (PDT) Date: Wed, 28 Apr 2021 12:52:37 -0700 From: Dmitry Torokhov To: Mattijs Korpershoek 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() Message-ID: References: <20210428164219.1115537-1-mkorpershoek@baylibre.com> <20210428164219.1115537-2-mkorpershoek@baylibre.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210428164219.1115537-2-mkorpershoek@baylibre.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. > > 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=-10.7 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_SIGNED,DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 630DEC433B4 for ; Wed, 28 Apr 2021 19:53:20 +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 943FF61419 for ; 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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org 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. > > 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=-10.7 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_SIGNED,DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 DA7EDC433ED for ; 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Wed, 28 Apr 2021 12:52:40 -0700 (PDT) Date: Wed, 28 Apr 2021 12:52:37 -0700 From: Dmitry Torokhov To: Mattijs Korpershoek 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() Message-ID: References: <20210428164219.1115537-1-mkorpershoek@baylibre.com> <20210428164219.1115537-2-mkorpershoek@baylibre.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210428164219.1115537-2-mkorpershoek@baylibre.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210428_125242_900609_942356E4 X-CRM114-Status: GOOD ( 26.30 ) 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 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. > > 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