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[23.128.96.18]) by mx.google.com with ESMTP id l8si11195561eds.308.2020.05.26.05.26.17; Tue, 26 May 2020 05:26:40 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@web.de header.s=dbaedf251592 header.b=OjBHhlsS; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731773AbgEZJLu (ORCPT + 99 others); Tue, 26 May 2020 05:11:50 -0400 Received: from mout.web.de ([212.227.17.12]:40165 "EHLO mout.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728682AbgEZJLu (ORCPT ); Tue, 26 May 2020 05:11:50 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=web.de; s=dbaedf251592; t=1590484301; bh=/E6hvivA05+qc1qjF8glQbdVCkS3pOI33LGy9LvZcBw=; h=X-UI-Sender-Class:Subject:To:Cc:References:From:Date:In-Reply-To; b=OjBHhlsSjrq5qBmqWjzzLzEasa/486Rmy23w7FUyqw3/HinHOB/kd0kEivIamh1c0 uhXVwEpqdtGjH+4AH8vJo/nTU3B28U1fEmVN5C1Hn+Hell1ONY+eVd0MpctuFaSYIp Zc/RsNTbqg0DRP8YBq7qXbCLnepEhLodfCUgRd0Q= X-UI-Sender-Class: c548c8c5-30a9-4db5-a2e7-cb6cb037b8f9 Received: from [192.168.1.2] ([93.131.141.233]) by smtp.web.de (mrweb106 [213.165.67.124]) with ESMTPSA (Nemesis) id 1MXGOC-1jWITr2vuQ-00YsXm; Tue, 26 May 2020 11:11:41 +0200 Subject: Re: [v3] workqueue: Fix double kfree for rescuer To: Lai Jiangshan , Zhang Qiang Cc: Tejun Heo , LKML , kernel-janitors@vger.kernel.org References: <20200525093019.2253-1-qiang.zhang@windriver.com> From: Markus Elfring Autocrypt: addr=Markus.Elfring@web.de; prefer-encrypt=mutual; keydata= mQINBFg2+xABEADBJW2hoUoFXVFWTeKbqqif8VjszdMkriilx90WB5c0ddWQX14h6w5bT/A8 +v43YoGpDNyhgA0w9CEhuwfZrE91GocMtjLO67TAc2i2nxMc/FJRDI0OemO4VJ9RwID6ltwt mpVJgXGKkNJ1ey+QOXouzlErVvE2fRh+KXXN1Q7fSmTJlAW9XJYHS3BDHb0uRpymRSX3O+E2 lA87C7R8qAigPDZi6Z7UmwIA83ZMKXQ5stA0lhPyYgQcM7fh7V4ZYhnR0I5/qkUoxKpqaYLp YHBczVP+Zx/zHOM0KQphOMbU7X3c1pmMruoe6ti9uZzqZSLsF+NKXFEPBS665tQr66HJvZvY GMDlntZFAZ6xQvCC1r3MGoxEC1tuEa24vPCC9RZ9wk2sY5Csbva0WwYv3WKRZZBv8eIhGMxs rcpeGShRFyZ/0BYO53wZAPV1pEhGLLxd8eLN/nEWjJE0ejakPC1H/mt5F+yQBJAzz9JzbToU 5jKLu0SugNI18MspJut8AiA1M44CIWrNHXvWsQ+nnBKHDHHYZu7MoXlOmB32ndsfPthR3GSv jN7YD4Ad724H8fhRijmC1+RpuSce7w2JLj5cYj4MlccmNb8YUxsE8brY2WkXQYS8Ivse39MX BE66MQN0r5DQ6oqgoJ4gHIVBUv/ZwgcmUNS5gQkNCFA0dWXznQARAQABtCZNYXJrdXMgRWxm cmluZyA8TWFya3VzLkVsZnJpbmdAd2ViLmRlPokCVAQTAQgAPhYhBHDP0hzibeXjwQ/ITuU9 Figxg9azBQJYNvsQAhsjBQkJZgGABQsJCAcCBhUICQoLAgQWAgMBAh4BAheAAAoJEOU9Figx g9azcyMP/iVihZkZ4VyH3/wlV3nRiXvSreqg+pGPI3c8J6DjP9zvz7QHN35zWM++1yNek7Ar OVXwuKBo18ASlYzZPTFJZwQQdkZSV+atwIzG3US50ZZ4p7VyUuDuQQVVqFlaf6qZOkwHSnk+ CeGxlDz1POSHY17VbJG2CzPuqMfgBtqIU1dODFLpFq4oIAwEOG6fxRa59qbsTLXxyw+PzRaR LIjVOit28raM83Efk07JKow8URb4u1n7k9RGAcnsM5/WMLRbDYjWTx0lJ2WO9zYwPgRykhn2 sOyJVXk9xVESGTwEPbTtfHM+4x0n0gC6GzfTMvwvZ9G6xoM0S4/+lgbaaa9t5tT/PrsvJiob kfqDrPbmSwr2G5mHnSM9M7B+w8odjmQFOwAjfcxoVIHxC4Cl/GAAKsX3KNKTspCHR0Yag78w i8duH/eEd4tB8twcqCi3aCgWoIrhjNS0myusmuA89kAWFFW5z26qNCOefovCx8drdMXQfMYv g5lRk821ZCNBosfRUvcMXoY6lTwHLIDrEfkJQtjxfdTlWQdwr0mM5ye7vd83AManSQwutgpI q+wE8CNY2VN9xAlE7OhcmWXlnAw3MJLW863SXdGlnkA3N+U4BoKQSIToGuXARQ14IMNvfeKX NphLPpUUnUNdfxAHu/S3tPTc/E/oePbHo794dnEm57LuuQINBFg2+xABEADZg/T+4o5qj4cw nd0G5pFy7ACxk28mSrLuva9tyzqPgRZ2bdPiwNXJUvBg1es2u81urekeUvGvnERB/TKekp25 4wU3I2lEhIXj5NVdLc6eU5czZQs4YEZbu1U5iqhhZmKhlLrhLlZv2whLOXRlLwi4jAzXIZAu 76mT813jbczl2dwxFxcT8XRzk9+dwzNTdOg75683uinMgskiiul+dzd6sumdOhRZR7YBT+xC wzfykOgBKnzfFscMwKR0iuHNB+VdEnZw80XGZi4N1ku81DHxmo2HG3icg7CwO1ih2jx8ik0r riIyMhJrTXgR1hF6kQnX7p2mXe6K0s8tQFK0ZZmYpZuGYYsV05OvU8yqrRVL/GYvy4Xgplm3 DuMuC7/A9/BfmxZVEPAS1gW6QQ8vSO4zf60zREKoSNYeiv+tURM2KOEj8tCMZN3k3sNASfoG fMvTvOjT0yzMbJsI1jwLwy5uA2JVdSLoWzBD8awZ2X/eCU9YDZeGuWmxzIHvkuMj8FfX8cK/ 2m437UA877eqmcgiEy/3B7XeHUipOL83gjfq4ETzVmxVswkVvZvR6j2blQVr+MhCZPq83Ota xNB7QptPxJuNRZ49gtT6uQkyGI+2daXqkj/Mot5tKxNKtM1Vbr/3b+AEMA7qLz7QjhgGJcie qp4b0gELjY1Oe9dBAXMiDwARAQABiQI8BBgBCAAmFiEEcM/SHOJt5ePBD8hO5T0WKDGD1rMF Alg2+xACGwwFCQlmAYAACgkQ5T0WKDGD1rOYSw/+P6fYSZjTJDAl9XNfXRjRRyJSfaw6N1pA Ahuu0MIa3djFRuFCrAHUaaFZf5V2iW5xhGnrhDwE1Ksf7tlstSne/G0a+Ef7vhUyeTn6U/0m +/BrsCsBUXhqeNuraGUtaleatQijXfuemUwgB+mE3B0SobE601XLo6MYIhPh8MG32MKO5kOY hB5jzyor7WoN3ETVNQoGgMzPVWIRElwpcXr+yGoTLAOpG7nkAUBBj9n9TPpSdt/npfok9ZfL /Q+ranrxb2Cy4tvOPxeVfR58XveX85ICrW9VHPVq9sJf/a24bMm6+qEg1V/G7u/AM3fM8U2m tdrTqOrfxklZ7beppGKzC1/WLrcr072vrdiN0icyOHQlfWmaPv0pUnW3AwtiMYngT96BevfA qlwaymjPTvH+cTXScnbydfOQW8220JQwykUe+sHRZfAF5TS2YCkQvsyf7vIpSqo/ttDk4+xc Z/wsLiWTgKlih2QYULvW61XU+mWsK8+ZlYUrRMpkauN4CJ5yTpvp+Orcz5KixHQmc5tbkLWf x0n1QFc1xxJhbzN+r9djSGGN/5IBDfUqSANC8cWzHpWaHmSuU3JSAMB/N+yQjIad2ztTckZY pwT6oxng29LzZspTYUEzMz3wK2jQHw+U66qBFk8whA7B2uAU1QdGyPgahLYSOa4XAEGb6wbI FEE= Message-ID: <5e1582ac-2f89-80cb-283d-57ba5003890f@web.de> Date: Tue, 26 May 2020 11:11:40 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-GB X-Provags-ID: V03:K1:MN4RE7QSo/P9fckSg8VfDd5UiNXTdNAVQXC+XN4bydpj2dNbUru fZNtcT693mWEOu2anGh6MXMqD+FZ7G0mvCj5hqCpcDJxMAujczTyEarhbNC0aTCfbeHdHny h3QO0tEDQp7+F1oxLinCJFJrUZHZkh7+oSSvX8zzroOFazmQjIfCqXNhi9BgKPkeLElLqEG 3iKQNnA5Q9+campRUIfhw== X-Spam-Flag: NO X-UI-Out-Filterresults: notjunk:1;V03:K0:xo+kCO12k20=:Sb7BFVxSbdVrGRCCBICOxf O2OUWMCNjfZpPG9yNgxsIvVHYvaurLFbd/MZ6BmBXfX5pxeBxRJxuZbgNcBqnUoIUx4xoV2On eE8nXxIc41CvKY1Ui3cwJPbvJ/QNmXaLTS7VzDR/7UtV/DVEjFcoECye1+yZzXmidhScbcR1R 720u3MkNR6a9kSiPQSzQPbZT789rHHdcbEGaGEskgfvgFTquu7QCBY932ISrUxRL1ihR+BwSx A++nQb7nsWJg4Gx7VGtqY9W5DS2tAnFAstge9s9ke5EFynj9pbs4Pbl0BjYkLe/5B7W1CJHim tW0KrA/6tbVJXoSNKpAhiiFHPQOMQeo4EktohQQPz+OVPTlOQ7P8cInCH2tc/JlwVYnX0xOGm lUEKSbzMDLBTk94WOgu+zdv9fzE7/2yu2bF6TpHKLKmzQhmTxPVWg9HEswYd73Z2Q8tm/dJbf algoWDA0RH+8H9U06Z7DNQon06d+oR9q+OrthEW6wC7lceUCmFJ827Wj3VXO4NAxiEqCQhKg1 XFyacA9pBEZPfGlzeXhbwulsdb0dbxXNKKoo+5wSVex1MqIHiUYBHx43l/8pQMO1BOdVXCKKZ ebTw3GWOASUYCxXLqci4sqU8YtCvdmH651cS5OY3b2TCrj5OBjtnxh1ABaYPytt/8U7BXSKYh uR2npvSnBgnXV8JF8VOFqUrOL8Bt3AmjtwNeMNHm257k8q1/a2wq0zxiQuwA48fBv5E+IiEwo BubExafiM7ripUqRJJXz/6SmZBRIQxErr+uullBl1yeIZDQQoQQcPamAAENjzD23N47m/AK/4 k/GBysCqnIRFjO/ykyLvU9PaS74wcwIU0+ZrFXJhqFN9M2ixO2fIxB42D2+eJUbtyDSV9joWP uVy2ysFvYgB1xvREzc7DSq30zIbR1sNFoO1e8cI/FGucjJqRqNc11TsnjGhVxnstZDUUnvrMY +lI1nyxs1MJeglSdregplOh0heqOBHzuKUjvBMd52ZlOnEdUjnUeMR4GkDfBj5kRKJcLrLLiw OLh7m8yO+4rxdzcT94gcHX8qa/WHRw8URbL5O2izvcIP6HOzSCBgSSlYWXvT4KnsqtrcqKKLE gS8LlibQ6Ar9GbfgrnSjAryn40ryMiCD8AdIb5UTSvfz4/7WLU7OhwCNoMmywmbnG5GBNNwFo AQxw3Sgoe4vjCK917HWgt1ffxoWqvP94K4i4N6Ik4QosPgJQcrRLvXIcYK/qfg1YhtVs2rKYC AK2WBu2OpivWRer/Z Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > wq->rescuer is guaranteed to be NULL in rcu_free_wq() I was unsure about this data processing detail. > The patch is a cleanup to remove a "kfree(NULL);". I would prefer also an improved commit message according to the understanding of the software situation in this direction. Regards, Markus