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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id DD7A2C433FE for ; Mon, 7 Feb 2022 22:53:34 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 40DA66B0073; Mon, 7 Feb 2022 17:53:34 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 3B8A36B0075; Mon, 7 Feb 2022 17:53:34 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2A8176B0078; Mon, 7 Feb 2022 17:53:34 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0105.hostedemail.com [216.40.44.105]) by kanga.kvack.org (Postfix) with ESMTP id 1C47E6B0075 for ; Mon, 7 Feb 2022 17:53:34 -0500 (EST) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id C6E1F180D330E for ; Mon, 7 Feb 2022 22:53:33 +0000 (UTC) X-FDA: 79117487106.14.F371C9C Received: from mail-yb1-f171.google.com (mail-yb1-f171.google.com [209.85.219.171]) by imf07.hostedemail.com (Postfix) with ESMTP id 301C140007; Mon, 7 Feb 2022 22:53:33 +0000 (UTC) Received: by mail-yb1-f171.google.com with SMTP id bt13so20599818ybb.2; Mon, 07 Feb 2022 14:53:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=khCuXFvktKenvt0NMs7br3GwZ3/YeGP6WmAl4hcRAtk=; b=kpXQP4l5WqQVZcPI2J7GhEMqRblCCx/VRl+7iJydLg96usujA3KkyvhEDN8DAxkZrC VqNQE2h1mUw9YHBsuHDWeCSqBv7hN2FtGHYPBnPFuVYbUO4b6eFwMorU0hNXO0hFHfqJ LH9ZfKHrUD9BIxCdMloGbBLY83ikW/eYozz6FCJN5KLYDKjZvCwBdm24RNLvaha87PF/ 9d21FkIthNP97QSw5w5kozooVmpSzF9o5ARO2dod2p6VRtFAb54CBjPdMCQ9mYa3UuhT wiRoyL2/Vgfj+NQH7GbZ4UCDrjQ6iOX4wO9+6zkestoQ0q2WCsWTwDsTqHxwi6Y1r1OI jnUg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=khCuXFvktKenvt0NMs7br3GwZ3/YeGP6WmAl4hcRAtk=; b=tHwa1ACckRJ8STvdtSOrcy95+6E5zwxchmF8bNREVSA3cF31dqknaq5v6LANLvntRN QKT2vIlj4SidSYi/lg0KqO4fs5Pte6Pz8qRs438fl3UO7Al0blFtIfxt76RsangrvS8V 6Z5/kTFFc20UTmbm74l7RPGgGI6iA/VA9gfNvDnzjWF4xycpdbxX7oxYcRmMfTp36Lv3 XZ5xmvggueu9N3mQOGYAP3qDY9PUJxWmW5A92RwRnLON4YlZx9NrtWnN++2+47Y8xfU8 OW1AAOmWVEvCQ5urIw3brm07H8XHU+7xWgcTEENDzUPpZdv3vKDyFVjjHaWueXkm6lrm CSrA== X-Gm-Message-State: AOAM531r+nPF/tbmF6PyFbd5gVMyU1ArzaLLPSi2SPi/WxJs/gTH+1cG +xKyUCF38jdBI9CHo2VtnG/RMPD9NtmhHZu0xYc= X-Google-Smtp-Source: ABdhPJwtR96yA0741OSUHlWaYDYM35eW1MyuwW/VLWiMWd373q68Xe4YJlgprQaxpU/4SKFiD85WcCUCA08nNOmIrX4= X-Received: by 2002:a25:148b:: with SMTP id 133mr2112718ybu.270.1644274412302; Mon, 07 Feb 2022 14:53:32 -0800 (PST) MIME-Version: 1.0 References: <20220121221021.60533b009c357d660791476e@linux-foundation.org> <20220122061228.nmuo75sDn%akpm@linux-foundation.org> In-Reply-To: From: Tong Zhang Date: Mon, 7 Feb 2022 14:53:21 -0800 Message-ID: Subject: Re: [PATCH] Fix regression due to "fs: move binfmt_misc sysctl to its own file" To: Luis Chamberlain Cc: Domenico Andreoli , "Eric W. Biederman" , David Airlie , Andrew Morton , amir73il@gmail.com, Andy Shevchenko , Arnd Bergmann , bcrl@kvack.org, benh@kernel.crashing.org, clemens@ladisch.de, crope@iki.fi, dgilbert@interlog.com, Greg KH , jack@suse.cz, jani.nikula@intel.com, jani.nikula@linux.intel.com, "James E.J. Bottomley" , jlbec@evilplan.org, john.ogness@linutronix.de, joonas.lahtinen@linux.intel.com, Joseph Qi , julia.lawall@inria.fr, Kees Cook , kernel@tuxforce.de, Linux Memory Management List , mark@fasheh.com, "Martin K. Petersen" , mm-commits@vger.kernel.org, nixiaoming@huawei.com, penguin-kernel@i-love.sakura.ne.jp, peterz@infradead.org, phil@philpotter.co.uk, pjt@google.com, pmladek@suse.com, rafael@kernel.org, rodrigo.vivi@intel.com, rostedt@goodmis.org, senozhatsky@chromium.org, sre@kernel.org, steve@sk2.org, surenb@google.com, torvalds@linux-foundation.org, tytso@mit.edu, Al Viro , wangqing@vivo.com, Iurii Zaikin , open list Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 301C140007 X-Rspam-User: nil Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=kpXQP4l5; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf07.hostedemail.com: domain of ztong0001@gmail.com designates 209.85.219.171 as permitted sender) smtp.mailfrom=ztong0001@gmail.com X-Stat-Signature: 37f384pqzsg1up5cbwffqw111zetapxd X-Rspamd-Server: rspam08 X-HE-Tag: 1644274413-889487 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Feb 7, 2022 at 1:46 PM Luis Chamberlain wrote: > > OK I think the issue here should have been that declaring this on > fs/binfmt_misc.c creates the chicken and the egg issue, and so we > need to do this on built-in code. Instead of your patch can you try > this instead, it just always creates the sysctl mount always now > so long as proc sysctl is enabled. It does not do the unregistration > as we always want the path present as it used to be before as well. > > diff --git a/fs/file_table.c b/fs/file_table.c > index 57edef16dce4..4f4739c9405c 100644 > --- a/fs/file_table.c > +++ b/fs/file_table.c > @@ -119,6 +119,7 @@ static struct ctl_table fs_stat_sysctls[] = { > static int __init init_fs_stat_sysctls(void) > { > register_sysctl_init("fs", fs_stat_sysctls); > + register_sysctl_mount_point("fs/binfmt_misc"); > return 0; > } > fs_initcall(init_fs_stat_sysctls); I'm looking at the original code, and it seems that if we don't select CONFIG_BINFMT_MISC at all, this file won't be created. This would suggest an IF MACRO around > + register_sysctl_mount_point("fs/binfmt_misc"); and it should looks like +#if IS_ENABLED(CONFIG_BINFMT_MISC) + register_sysctl_mount_point("fs/binfmt_misc"); +#endif or if you prefer original style: #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE) - Tong