From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Subject: Re: [PATCH 00/10] sysfs tagged directories Date: Wed, 30 Apr 2008 20:12:28 -0700 Message-ID: <20080501031228.GC4911@suse.de> References: <20080429171015.473938697@theryb.frec.bull.fr> <20080429173621.GA16625@suse.de> <20080429180445.GA18110@sergelap.austin.ibm.com> <20080429184151.GA19794@suse.de> <20080429193417.GA19282@sergelap.austin.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Benjamin Thery , linux-kernel@vger.kernel.org, Al Viro , "Eric W. Biederman" , Tejun Heo , Daniel Lezcano , Pavel Emelyanov , netdev@vger.kernel.org To: "Serge E. Hallyn" Return-path: Content-Disposition: inline In-Reply-To: <20080429193417.GA19282@sergelap.austin.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Tue, Apr 29, 2008 at 02:34:17PM -0500, Serge E. Hallyn wrote: > Quoting Greg KH (gregkh@suse.de): > > On Tue, Apr 29, 2008 at 01:04:45PM -0500, Serge E. Hallyn wrote: > > > Quoting Greg KH (gregkh@suse.de): > > > > On Tue, Apr 29, 2008 at 07:10:15PM +0200, Benjamin Thery wrote: > > > > > Here is the announcement Eric wrote back in December to introduce his > > > > > patchset: > > > > > > > > > > > > > > > > Are the objections that Al Viro made to this patchset when it was last > > > > sent out addressed in this new series? > > > > > > > > thanks, > > > > > > > > greg k-h > > > > > > Which objections were those? The last submission which I see by Eric > > > was http://lkml.org/lkml/2007/12/1/15 this past December. I see no > > > response from Al and get the feeling you were ok with them. > > > > > > So my hunch would be that Eric had addressed those before that last > > > submission, but if not I'm sorry, and please do set me straight. > > > > See the thread from Al starting with: > > Date: Mon, 7 Jan 2008 10:24:17 +0000 > > From: Al Viro > > To: "Eric W. Biederman" > > Cc: linux-kernel@vger.kernel.org, htejun@gmail.com, > > linux-fsdevel@vger.kernel.org, gregkh@suse.de > > Subject: [RFC] netns / sysfs interaction > > Message-ID: <20080107072301.GW27894@ZenIV.linux.org.uk> > > > > He had a lot of questions and objections to this way forward, and I > > share those objections. > > Ah I see it, thanks. > > All Al's questions appear to be about how a task migration will be handled > in the face of funky userspace usage of sysfs files. But it seems clear the > first use of these will not be for migration but for vservers. The key > thing to remember is that we don't (as decided at kernel-summit 06) aim > to hide from userspace the fact that it's in a vserver, we just give it > what it needs so that it can pretend. > > As we start implementing checkpoint and restart to effect migration, > *clearly* if we're trying to restart a task which has cwd or an open fd > in /sys/class/net/eth42/, but that directory doesn't exist on the target > machine, then the restart (and hence migrate) fails. > > There was a concern about > /sys/devices/pci0000\:00/0000\:00\:0a.0/net:eth0. Since that's a > symlink to ../../../class/net/eth0, it will either point nowhere or > point to the virtualized eth0, if veth1 (or vethN) was renamed to eth0 > in the container. (see below) If that is the wrong thing to do we > could try to address it in this patchset, but I suspect it is better > left until device namespace are implemented. Does that sounds sane? I really don't think so, but I'll wait for the reworked patches to review them and see how badly they mess the code up :) thanks, greg k-h