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 16E65C433FE for ; Wed, 9 Feb 2022 07:55:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9DB636B0073; Wed, 9 Feb 2022 02:55:17 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 98AA76B0075; Wed, 9 Feb 2022 02:55:17 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8A1706B0074; Wed, 9 Feb 2022 02:55:17 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0048.hostedemail.com [216.40.44.48]) by kanga.kvack.org (Postfix) with ESMTP id 74F9B6B0073 for ; Wed, 9 Feb 2022 02:55:17 -0500 (EST) Received: from smtpin31.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 27998181D2090 for ; Wed, 9 Feb 2022 07:55:17 +0000 (UTC) X-FDA: 79122481074.31.5388887 Received: from mail-yb1-f175.google.com (mail-yb1-f175.google.com [209.85.219.175]) by imf10.hostedemail.com (Postfix) with ESMTP id 6E490C0003; Wed, 9 Feb 2022 07:55:16 +0000 (UTC) Received: by mail-yb1-f175.google.com with SMTP id o19so3511752ybc.12; Tue, 08 Feb 2022 23:55:16 -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=eV794YHbVHS12HmSAomi+0BDrCTJ09pCtyoRkv+rxS4=; b=IaqQH2L1wqV8U/xN3pp1SpF/OBUrJpDXSlrwH7ehrNLbySHv9Wu27FnQCLrzuLW/9H 0aEUMxpKbcOuYT3UfYeXlElDk4AtxnL1fiDwxlR9fidIi+pymWn+be3W4iP+LrhR1HIZ t3k30fqsdNDFaaxi8YXi/rO7TvALjKbenZuYkWpXm1YywZngNy7K1Hma2dRZV8dzNooF VVo+ma88TWMFfxjPhMjY4hJ5xBAc0GFFL6u5Rhn0e5HBKHTWYwQagu8p1JQ8+QopwgIM lyYnjdMQIW2Jyo/BUaUtMNebOs0Rb8aHZrdgvCb+UB1WLg2FOSn+lytIsJNPg367umDb IgRQ== 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=eV794YHbVHS12HmSAomi+0BDrCTJ09pCtyoRkv+rxS4=; b=PopxOf269ThQ+clAw2dmZ91YptVHwMbFSn/ecZ2Etdh/IhWjb0GQW3r9chXUpo3SFH 9guP6A74KZ8TKwaj5DkfgmhIJb4AWrM86XLVVOJZzSghRrxpQi8WcaFcAje3WLEIga/L R6r2BJJQiavvOf9bz+IBP+OYHNor6ila3cSDoeg1FyFf9ntWAXSIysWu7aDx4L4kDVX2 5OefzFp1sKnnQv6o7KuhIIzXfGY06JFo/o5PQHHtJCMU3kSnRWeEmU7bQRCBla6qo9sv vODqZv7AnNs5X2q1QqkJJ/ZP+Y8oIF8hcOjaAAXan0tTgA2/OTd7dc4+TOlOMLHDDTcC iI4w== X-Gm-Message-State: AOAM533E7kBptRAHBBg32LO1mAU42T0skwSFLpqiCtyOgaAWA4znYBHh ZtgQV9n342PvHP+FJIsWWvsVuxoo10pLHJC6TgY= X-Google-Smtp-Source: ABdhPJyYT4RXELVDsNxwkCYFgUOkQSg0SKPK6EQFP3US4fA/3rH2ApxDKrTuSpdjytjxSGybeJS7lxyFXdGT7d71NZg= X-Received: by 2002:a05:6902:4c2:: with SMTP id v2mr1053884ybs.429.1644393315563; Tue, 08 Feb 2022 23:55:15 -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: Tue, 8 Feb 2022 23:55:04 -0800 Message-ID: Subject: Re: [PATCH v2] Fix regression due to "fs: move binfmt_misc sysctl to its own file" To: Domenico Andreoli Cc: Luis Chamberlain , "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 , "Martin K. Petersen" , mm-commits@vger.kernel.org, nixiaoming@huawei.com, penguin-kernel@i-love.sakura.ne.jp, peterz@infradead.org, Phillip Potter , Paul Turner , pmladek@suse.com, rafael@kernel.org, rodrigo.vivi@intel.com, rostedt@goodmis.org, senozhatsky@chromium.org, sre@kernel.org, steve@sk2.org, Suren Baghdasaryan , torvalds@linux-foundation.org, tytso@mit.edu, Al Viro , wangqing@vivo.com, Iurii Zaikin , open list , regressions@lists.linux.dev Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: xx6d63a9ifgf95sbctbimrixzipjopq6 Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=IaqQH2L1; spf=pass (imf10.hostedemail.com: domain of ztong0001@gmail.com designates 209.85.219.175 as permitted sender) smtp.mailfrom=ztong0001@gmail.com; dmarc=pass (policy=none) header.from=gmail.com X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 6E490C0003 X-HE-Tag: 1644393316-885998 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 Tue, Feb 8, 2022 at 11:49 PM Domenico Andreoli wrote: > > Commit 3ba442d5331f did not go unnoticed, binfmt-support stopped to > work on my Debian system since v5.17-rc2 (did not check with -rc1). > > The existance of the /proc/sys/fs/binfmt_misc is a precondition for > attempting to mount the binfmt_misc fs, which in turn triggers the > autoload of the binfmt_misc module. Without it, no module is loaded > and no binfmt is available at boot. > > Building as built-in or manually loading the module and mounting the fs > works fine, it's therefore only a matter of interaction with user-space. > I could try to improve the Debian systemd configuration but I can't > say anything about the other distributions. > > This patch restores a working system right after boot. > > v2: > - move creation of fs/binfmt_misc to fs/file_table.c > - use IS_ENABLED() to conditionally create it > > Fixes: 3ba442d5331f ("fs: move binfmt_misc sysctl to its own file") > Signed-off-by: Domenico Andreoli > Cc: Al Viro > Cc: Amir Goldstein > Cc: Andrew Morton > Cc: Andy Shevchenko > Cc: Antti Palosaari > Cc: Arnd Bergmann > Cc: Benjamin Herrenschmidt > Cc: Benjamin LaHaise > Cc: Clemens Ladisch > Cc: David Airlie > Cc: Douglas Gilbert > Cc: Eric Biederman > Cc: Greg Kroah-Hartman > Cc: Iurii Zaikin > Cc: James E.J. Bottomley > Cc: Jan Kara > Cc: Jani Nikula > Cc: Jani Nikula > Cc: Joel Becker > Cc: John Ogness > Cc: Joonas Lahtinen > Cc: Joseph Qi > Cc: Julia Lawall > Cc: Kees Cook > Cc: Lukas Middendorf > Cc: Mark Fasheh > Cc: Martin K. Petersen > Cc: Paul Turner > Cc: Peter Zijlstra > Cc: Petr Mladek > Cc: Phillip Potter > Cc: Qing Wang > Cc: "Rafael J. Wysocki" > Cc: Rodrigo Vivi > Cc: Sebastian Reichel > Cc: Sergey Senozhatsky > Cc: Stephen Kitt > Cc: Steven Rostedt (VMware) > Cc: Suren Baghdasaryan > Cc: Tetsuo Handa > Cc: "Theodore Ts'o" > Cc: Xiaoming Ni > > --- > fs/binfmt_misc.c | 6 +----- > fs/file_table.c | 2 ++ > 2 files changed, 3 insertions(+), 5 deletions(-) > > Index: b/fs/binfmt_misc.c > =================================================================== > --- a/fs/binfmt_misc.c > +++ b/fs/binfmt_misc.c > @@ -817,20 +817,16 @@ static struct file_system_type bm_fs_typ > }; > MODULE_ALIAS_FS("binfmt_misc"); > > -static struct ctl_table_header *binfmt_misc_header; > - > static int __init init_misc_binfmt(void) > { > int err = register_filesystem(&bm_fs_type); > if (!err) > insert_binfmt(&misc_format); > - binfmt_misc_header = register_sysctl_mount_point("fs/binfmt_misc"); > - return 0; > + return err; > } > > static void __exit exit_misc_binfmt(void) > { > - unregister_sysctl_table(binfmt_misc_header); > unregister_binfmt(&misc_format); > unregister_filesystem(&bm_fs_type); > } > Index: b/fs/file_table.c > =================================================================== > --- a/fs/file_table.c > +++ b/fs/file_table.c > @@ -119,6 +119,8 @@ static struct ctl_table fs_stat_sysctls[ > static int __init init_fs_stat_sysctls(void) > { > register_sysctl_init("fs", fs_stat_sysctls); > + if (IS_ENABLED(CONFIG_BINFMT_MISC)) > + register_sysctl_mount_point("fs/binfmt_misc"); > return 0; > } > fs_initcall(init_fs_stat_sysctls); Looks good Thanks! Reviewed-by: Tong Zhang