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=-7.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 DADFEC2D0C6 for ; Sat, 28 Dec 2019 12:26:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 969D9207E0 for ; Sat, 28 Dec 2019 12:26:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=web.de header.i=@web.de header.b="ltveeDlN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726597AbfL1M0C (ORCPT ); Sat, 28 Dec 2019 07:26:02 -0500 Received: from mout.web.de ([212.227.17.11]:47723 "EHLO mout.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726377AbfL1M0C (ORCPT ); Sat, 28 Dec 2019 07:26:02 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=web.de; s=dbaedf251592; t=1577535951; bh=n6RC+2F495ghd/0ICzcAKDXGWf8tVEvndTkoVgGfxHE=; h=X-UI-Sender-Class:To:Cc:References:Subject:From:Date:In-Reply-To; b=ltveeDlNccmcd0mKt4h090+1FqDokYC8PuJCjLghVRe2UmQx/NfDu/GExObQjveuD 7xlR/+3n7x1nwDdpSDIVnkOiU0M37m5+neX68OP7ayxyK1Yxhlk9SONtDdXSo0yAfF o1P+c5gA0x9uvLFQd0KHn4odq814agre7KQbl8oY= X-UI-Sender-Class: c548c8c5-30a9-4db5-a2e7-cb6cb037b8f9 Received: from [192.168.1.2] ([78.48.3.151]) by smtp.web.de (mrweb102 [213.165.67.124]) with ESMTPSA (Nemesis) id 0MGzXS-1ixsku3aa2-00DrXX; Sat, 28 Dec 2019 13:25:50 +0100 To: Xu Wang , Srinivas Kandagatla , kernel-janitors@vger.kernel.org Cc: linux-kernel@vger.kernel.org References: <1577438434-9945-1-git-send-email-vulab@iscas.ac.cn> Subject: Re: nvmem: core: Checking the decrementing of reference counters From: Markus Elfring Autocrypt: addr=Markus.Elfring@web.de; 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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.3.1 MIME-Version: 1.0 In-Reply-To: <1577438434-9945-1-git-send-email-vulab@iscas.ac.cn> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:8JmaXCBanrGdFXwC198kewP5yhXVBp0/zIcjsLSX/6KWvOhh70B GANw32gXJ3hT5OdEox4NV4aoCZfBsLyKM7jKM0SjjECngd5VZIFfPG09fkzcijZlCZKok+V ccVDe+VPJGM0BTfSJFvYMQacNgP0Viy+6R+XZZ4rFEVTYWm/EvSjvYQ8sqfuMUiRyXtWd5z TbAdGtQVpWRrO0WXtpwAw== X-UI-Out-Filterresults: notjunk:1;V03:K0:nycj1l2HX9Q=:8NKg6aYWXtlCZF0mxMQ7Jx C8mLYCUaEyMJp9zxn5HSHpPFcGc3CgKjtzUj9uN8hE7BcouCsaQ2xk3ee25ApPGZ3l+9IfLyn T6d0ZILfZntrWZKrP8Y4jAL+SP5Cx0z6S4641l4fhGX4c/uQx7K3VfYKM70w8ca36YUKSj5iq hQp3yuUTZlzWRyD69xQDDV4VOubHAn7plObShKr9OlJDeLJAYgbVeUU3dDMdYTAvvTPw6rZ81 nXc74Hqm5+8Qe3MqiPxxw0Y6Vybtt0t06AZYnzGTHbuPjMsrEVBImO4/1Bv2hHiDmTPHXwQUg EZL5ppD/uYw3QryuqifcX0TCZFd/hnF5fcur56VGHrQFS+B8+Kvv27BdYZZYorAwXC1ojW6qD kcqTg1VccEnY5MA0jFbJEDNXWpgH7KnCSzJTTAN9SKiOy+Ft2dD+hDIxw72viGm6S6kU6Qlrv 6D4S5GHIQq7NgtYeerjHlCadDSqTkGKsx7yCvKjlC9xiLK328Uu+wBPBaw7gKbVaLw86HYgeq ZeYVxtDDJO1qozhGCS2zgTBsZ3VtBqgCrWBtAX4rJYS5h8IRNBhqAmSit05OwTmMGE4EXSFY0 s2Xz5hDaHIJ+26OMp9xRjxY4XuAl+AqhjbXyV3Wv+8U6lqOE6txgxbc7J5BWQqzZll2TDAyu2 4jec3wxNwwg09+wxcOeUIMGxwIMuT09sx5MaMcnW2un8FjeD2hgIeBlmA7f9U10DXOjUT4xvT Fbqn56JFVmETBAeYxHKXaux5a8WgFqzK+4CYFg74l1jszA/bjpjNPOXHvQTGuHVNj+4gwspFH CBVCj7yUkUsN1pc9laYSw/Gh73gcQ1KXuVTQsrk4UrcLSsItn486Kic5EvVhEFrKC/oST3nZn gmItsVEhHjMg3h9FStEtjSuzN30yB7fB74GlG1iRqcrOEdoEsiYlhRMwV+3hXvOVXpUeDryJP BpOdz5DmaViEUN33myFEhaavDNcSSm7OSOkS9c8MIUeHyPAJSGDeSN56R4E1uknhvwmRPW0Ui JPAQPfnwFd4EMb3CGYbzuqayotH6HIShZ3KyEyxTpT8opJ4bG992gKitrlc3HfY6afy7XCEeG DJQbjgHjIyjy2cmsjNQUcSWV3AnABrVaAhejI+rurx0/xeE11vlozu274NZaS/jK+rCxlc114 v+C8rLmJDfe8xULk0GseVdLC6icvF1NS/6eRQsVZs0mgCW7Q7zJ87J527x+sAdwlpZaWXQ7vf 5uAwzeQBQs13wxhoPFHImB+QTs4MMSZHuw6rhTOM524i4vb44dB5sbRjMuM8= Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I have taken another look at the implementation of the function =E2=80=9Cn= vmem_device_release=E2=80=9D. https://elixir.bootlin.com/linux/v5.5-rc3/source/drivers/nvmem/core.c#L421 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/dr= ivers/nvmem/core.c?id=3Dbf8d1cd4386535004c4afe7f03d37f9864c9940e#n421 Now I wonder why the statement =E2=80=9Cput_device(&nvmem->dev)=E2=80=9D i= s performed here after it was also executed by the function =E2=80=9C__nvmem_device_put=E2= =80=9D before. How often should the device reference count be decremented (at the end)? Regards, Markus