Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755093AbbKWPkV (ORCPT ); Mon, 23 Nov 2015 10:40:21 -0500 Received: from mail-yk0-f175.google.com ([209.85.160.175]:36330 "EHLO mail-yk0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752553AbbKWPkS (ORCPT ); Mon, 23 Nov 2015 10:40:18 -0500 Date: Mon, 23 Nov 2015 10:40:13 -0500 From: Tejun Heo To: Daniel Borkmann Cc: Florian Westphal , davem@davemloft.net, pablo@netfilter.org, kaber@trash.net, kadlec@blackhole.kfki.hu, daniel.wagner@bmw-carit.de, nhorman@tuxdriver.co, lizefan@huawei.com, hannes@cmpxchg.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com, ninasc@fb.com, Neil Horman , Jan Engelhardt Subject: Re: [PATCH 9/9] netfilter: implement xt_cgroup cgroup2 path match Message-ID: <20151123154013.GB3049@mtj.duckdns.org> References: <1448122441-9335-1-git-send-email-tj@kernel.org> <1448122441-9335-10-git-send-email-tj@kernel.org> <20151121165605.GC25336@breakpoint.cc> <20151121170425.GD3428@htj.duckdns.org> <20151121185419.GD25336@breakpoint.cc> <565317F0.2030502@iogearbox.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <565317F0.2030502@iogearbox.net> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 925 Lines: 24 Hello, Daniel. On Mon, Nov 23, 2015 at 02:43:12PM +0100, Daniel Borkmann wrote: ... > Haven't looked deeply into kernfs, but if it's possible to get the object > from the struct file eventually, you could let iptables frontend open that > path and just pass the fd down. Would be sizeof(int) vs PATH_MAX then, i.e. > when you have a large number of rules to load. That works in one direction but not in the other. ie. You can tell the kernel the path that way but can't retrieve. If using path string is unacceptable, the best alternative would be an inode number rather than a fd; however, using an inode number would be quite cumbersome and painful too. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/