From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from zeniv.linux.org.uk (zeniv.linux.org.uk [62.89.141.173]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8BEE2213E90 for ; Sat, 6 Sep 2025 05:52:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.89.141.173 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757137964; cv=none; b=Sp/WE16FP+VN7HcbOfjOLk79lBU9ROj02BbxmLg1CBFExIsSI1AMYUtFdS4CfaVd+57wVUNcFWgmwcb1FCC7Z3bEesHTCxKNFMXaCBoGmtnXKCEK5JMqVvU2kTCxbxusoD9UHwc8xKM1vAc4ad3e9vOmri0fV2HQLkx94pgXOoE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757137964; c=relaxed/simple; bh=t8cZyuLNU/8oCDibkcn+E+PeqlXgYB2BZwuZ3lVDk84=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=GNR2AKztw1uk4gqNNszABJ+9j4vjW70F2EnClOSm9CpVHTxIuNJ8Vc6luK9BZAlGBbTk55oczmsMOr5tz3HUSMG17/nI7iBE4S+lj78pUZYxD2C89YbLbujba0YcWuaUG0o/3QPresBMspln8vGNFiYLAqTaOlWKhJNPpw+3Bn8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk; spf=none smtp.mailfrom=ftp.linux.org.uk; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b=jKTCEmwo; arc=none smtp.client-ip=62.89.141.173 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=ftp.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b="jKTCEmwo" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=linux.org.uk; s=zeniv-20220401; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=VCzrWvZFyyAOsVvfE8R711pjB6qmnO+kZ5FyggeR6V0=; b=jKTCEmwoo0aLVx0/tqbaD+WfN+ CLh5ZJ8ufs9DvFwpH2fUjT8AJyycJkHZGAFvf+uLX+wDyAD70PGj70d0GEM2fnjMtdzn6/e54UkAJ d0qWvKidWhuxlGaNTrDeszVibQ216lt5J+4Xi1JWS7CbX76HiSO7xTDlj03QAliLtXddZtTf6Ri9K JpRIGuApHUvz9omR3tk1bcLJdwgCzO2vV/Na6iNULo+FQMQN9gVCg6f8Vh8ZY+7v3OsuD0ilayHWd itToEMHaSBCHyjygfGDDYMi4vC0d8Ed1BYQ+OslWKtqAW310wKJ/3Km5Uc9NbhIMn1lXXJJJQtQJF rwf0y3OA==; Received: from viro by zeniv.linux.org.uk with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1uulqq-0000000FdWi-2wXV; Sat, 06 Sep 2025 05:52:40 +0000 Date: Sat, 6 Sep 2025 06:52:40 +0100 From: Al Viro To: NeilBrown Cc: Christian Brauner , Amir Goldstein , Jan Kara , linux-fsdevel@vger.kernel.org Subject: Re: [PATCH 1/6] fs/proc: Don't look root inode when creating "self" and "thread-self" Message-ID: <20250906055240.GT39973@ZenIV> References: <20250906050015.3158851-1-neilb@ownmail.net> <20250906050015.3158851-2-neilb@ownmail.net> <20250906055005.GS39973@ZenIV> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250906055005.GS39973@ZenIV> Sender: Al Viro On Sat, Sep 06, 2025 at 06:50:05AM +0100, Al Viro wrote: > On Sat, Sep 06, 2025 at 02:57:05PM +1000, NeilBrown wrote: > > From: NeilBrown > > > > proc_setup_self() and proc_setup_thread_self() are only called from > > proc_fill_super() which is before the filesystem is "live". So there is > > no need to lock the root directory when adding "self" and "thread-self". > > > > The locking rules are expected to change, so this locking will become > > anachronistic if we don't remove it. > > Please, leave that one alone. FWIW, in tree-in-dcache branch (will push > tomorrow or on Sunday, once I sort the fucking #work.f_path out) there's > this: PS: you do realize that we have similar things in devpts, binder, functionfs, etc., right? What's special about procfs?