From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Borkmann Subject: Re: [PATCH net-next 3/4] bpf: add support for persistent maps/progs Date: Fri, 23 Oct 2015 15:47:56 +0200 Message-ID: <562A3A8C.1060705@iogearbox.net> References: <562301F9.1030702@plumgrid.com> <5623B4B4.2010703@iogearbox.net> <5623CD8D.7000500@iogearbox.net> <56240814.8020105@plumgrid.com> <1445240171.3728424.413797809.230D716F@webmail.messagingengine.com> <5624BD0C.3070404@iogearbox.net> <5624FCDF.3090601@iogearbox.net> <562518B8.2070401@plumgrid.com> <56252A43.3000706@iogearbox.net> <56253335.9000206@plumgrid.com> <1445280385.602530.414418777.63627F89@webmail.messagingengine.com> <562545AA.2080207@plumgrid.com> <1445284997.621186.414538017.6E35B341@webmail.messagingengine.com> <56255714.2070800@plumgrid.com> <56256BF9.1090500@iogearbox.net> <56258B11.9080505@plumgrid.com> <5625FF71.8020304@iogearbox.net> <56267FAF.60206@plumgrid.com> <87io61fjx3.fsf@x220.int.ebiederm.org> <5627AC79.5000704@ iogearbox.net> <87a8rabsst.fsf@x220.int.ebiederm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: Alexei Starovoitov , Hannes Frederic Sowa , davem@davemloft.net, viro@ZenIV.linux.org.uk, tgraf@suug.ch, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Alexei Starovoitov To: "Eric W. Biederman" Return-path: In-Reply-To: <87a8rabsst.fsf@x220.int.ebiederm.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 10/22/2015 09:35 PM, Eric W. Biederman wrote: > Daniel Borkmann writes: >> On 10/20/2015 08:56 PM, Eric W. Biederman wrote: >> ... >>> Just FYI: Using a device for this kind of interface is pretty >>> much a non-starter as that quickly gets you into situations where >>> things do not work in containers. If someone gets a version of device >>> namespaces past GregKH it might be up for discussion to use character >>> devices. >> >> Okay, you are referring to this discussion here: >> >> http://thread.gmane.org/gmane.linux.kernel.containers/26760 > > That is a piece of it. It is an old old discussion (which generally has > been handled poorly). For the forseeable future device namespaces have > a firm NACK by GregKH. Which means that dynamic character device based > interfaces do not work in containers. Which means if you are not > talking about physical hardware, character devices are a poor fit. Yes, it breaks down with real namespace support. Reworking the set with an improved version of the fs code is already in progress. Thanks, Daniel