From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: [PATCH] locks: new procfs lockinfo Date: Thu, 23 Feb 2012 13:01:06 -0800 Message-ID: <20120223130106.8d976093.akpm@linux-foundation.org> References: <1329737454.3058.3.camel@offbook> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: dave@gnu.org, "J. Bruce Fields" , Matthew Wilcox , lkml , linux-fsdevel To: ebiederm@xmission.com (Eric W. Biederman) Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Wed, 22 Feb 2012 16:38:27 -0800 ebiederm@xmission.com (Eric W. Biederman) wrote: > Davidlohr Bueso writes: > > > From: Davidlohr Bueso > > > > Based on our previous discussion https://lkml.org/lkml/2012/2/10/462 we came to > > agree on deprecating the current /proc/locks in favor of a more extensible interface. > > The new /proc/lockinfo file exports similar information - except instead of maj:min the > > device name is shown - and entries are formated like those in /proc/cpuinfo, allowing us > > to add new entries without breaking userspace. > > You can't know the device name, attempt to say what you don't know seems > very dangerous. It may be reasonable to simply give the deivce number > and not split the device number into major/minor any more and I am > concerned about reality. I don't think we've ever been told any *reason* for switching from major:minor to device-name. This is a problem. And yes, major:minor reliably and uniquely identifies the device. I'm not sure that the human-readable string which is largely a convenience thing is as reliable as this.