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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D46EDD25030 for ; Sun, 11 Jan 2026 02:34:12 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 366116B0088; Sat, 10 Jan 2026 21:34:12 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 313926B0089; Sat, 10 Jan 2026 21:34:12 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 21FF56B008A; Sat, 10 Jan 2026 21:34:12 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 10B676B0088 for ; Sat, 10 Jan 2026 21:34:12 -0500 (EST) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 9CA70B82BB for ; Sun, 11 Jan 2026 02:34:11 +0000 (UTC) X-FDA: 84318113502.27.6074455 Received: from out-177.mta1.migadu.com (out-177.mta1.migadu.com [95.215.58.177]) by imf04.hostedemail.com (Postfix) with ESMTP id C9F2B4000A for ; Sun, 11 Jan 2026 02:34:09 +0000 (UTC) Authentication-Results: imf04.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b="LeS/cM1u"; spf=pass (imf04.hostedemail.com: domain of kent.overstreet@linux.dev designates 95.215.58.177 as permitted sender) smtp.mailfrom=kent.overstreet@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1768098850; a=rsa-sha256; cv=none; b=D2uFIGAugtNpAy0hyHdiN6d+/Za9n6WX0kAS6DEbt+xJOvfZIVSvmc4h+8Xc5182x+ecIU mNnbo2kTTsvFFDEc8CU8xCLvGtZECgebZIq3/0NV8jIqC8RF+suP3IWFuKIO3xc1L7OsYm kfGLOX4iO+0zZC2at68eg/Gdg3aLC6U= ARC-Authentication-Results: i=1; imf04.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b="LeS/cM1u"; spf=pass (imf04.hostedemail.com: domain of kent.overstreet@linux.dev designates 95.215.58.177 as permitted sender) smtp.mailfrom=kent.overstreet@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1768098850; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=/cq7IxD3DIIiFhsSmoe0bARTECHzyaMLAvMPQNM/M/A=; b=MIwpV0HarqOx13vzpz1R2PNVxRAK0MpDUWtwRw12fbCj9qFQaA7+4oyAJcWrVF1B+qovyI f7+roL02ElTWA3u4MsxyTc4d5Fs2IYtJ3Yg0gvqUd83YoVwJd/0EMmHR3co2HjXdgMhSyv p3q+LHSxbw9Co/+jYimqbKhNdktYq+M= Date: Sat, 10 Jan 2026 21:33:54 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1768098847; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=/cq7IxD3DIIiFhsSmoe0bARTECHzyaMLAvMPQNM/M/A=; b=LeS/cM1ugGnb/f5grZFTfWuOJNPjVbdRFcUPGaJoXQLwKCq5DRHYdbj0rVXizu1q+oMOny T4P1LJHup7Des3tQiG7UQORjN/zkmkZCra2ZWzG6O8jTRw7zPonueYqFLKVwhRPmYS3F+f UceqMSYahPgoeXUNsiyl1ZmcsWGviMs= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Kent Overstreet To: ranxiaokai627@163.com Cc: surenb@google.com, vbabka@suse.cz, akpm@linux-foundation.org, david@kernel.org, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, rppt@kernel.org, mhocko@suse.com, corbet@lwn.net, linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, ran.xiaokai@zte.com.cn Subject: Re: [PATCH] alloc_tag: remove sysctl prefix from mem_profiling boot parameter Message-ID: References: <20260109062419.157284-1-ranxiaokai627@163.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260109062419.157284-1-ranxiaokai627@163.com> X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: C9F2B4000A X-Stat-Signature: kdkftnar4mb8dag4h14jr37iksqda3gw X-Rspam-User: X-HE-Tag: 1768098849-266662 X-HE-Meta: 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 RlC9qJOo VADpqG8yquJHtpoSTBPP5p8Htb2Hrl1qYAe0el/EpmylfZ97XM2JrWR0NwyPLkyzwKNsRPGYccDvYBdfpMB/L0fV8JwCeHg1JDOFt38sHX3IsylOW37xSRvzstJgLU5YQA/O7Joy+4qJRQFHdHPXw7BUs8wcswSg6k3dpLKfts7KQr9yzfVrWme9EbpqB0rvxNju+5od0dX4FglMixmC+a9iNTCt+lFcXtKKbv5Hxf8KHtzb3IxGmU7I90ZeMs8vdYlyw 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: List-Subscribe: List-Unsubscribe: On Fri, Jan 09, 2026 at 06:24:19AM +0000, ranxiaokai627@163.com wrote: > From: Ran Xiaokai > > Boot parameters prefixed with "sysctl." are processed separately > during the final stage of system initialization via kernel_init()-> > do_sysctl_args(). Since mem_profiling support should be parsed > in early boot stage, it is unsuitable for centralized handling > in do_sysctl_args(). > Also, when CONFIG_MEM_ALLOC_PROFILING_DEBUG is enabled, > the sysctl.vm.mem_profiling entry is not writable and will cause > a warning. To prevent duplicate processing of sysctl.vm.mem_profiling, > rename the boot parameter to "mem_profiling". > > Signed-off-by: Ran Xiaokai How was this observed/detected? My reading of early_param() would seem to indicate that setup_early_mem_profiling() is getting called at the appropriate time - and then additionally a second time by do_sysctl_args(), which then becomes a noop. So the only bug would seem to be that the sysctl is not writeable in debug mode? There's an easier fix for that one...