From mboxrd@z Thu Jan 1 00:00:00 1970 From: Neil Brown Subject: Re: [PATCH -V3] Generic name to handle and open by handle syscalls Date: Mon, 26 Apr 2010 21:16:13 +1000 Message-ID: <20100426211613.33dc6076@notabene.brown> References: <1271960133-16414-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <20100424110812.40989988@notabene.brown> <20100426095658.GD23020@infradead.org> <20100426201633.0989254f@notabene.brown> <20100426102844.GA24515@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Andreas Dilger , Theodore Tso , "Aneesh Kumar K.V" , viro@zeniv.linux.org.uk, corbet@lwn.net, linux-fsdevel@vger.kernel.org, sfrench@us.ibm.com To: Christoph Hellwig Return-path: Received: from cantor.suse.de ([195.135.220.2]:59557 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752289Ab0DZLQ0 (ORCPT ); Mon, 26 Apr 2010 07:16:26 -0400 In-Reply-To: <20100426102844.GA24515@infradead.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Mon, 26 Apr 2010 06:28:44 -0400 Christoph Hellwig wrote: > On Mon, Apr 26, 2010 at 08:16:33PM +1000, Neil Brown wrote: > > uuids - as Ted as shown - are not necessarily unique (despite the name), > > so using them to perform a lookup will either be imperfect (not good for a > > kernel interface) or will impose extra uniqueness which would break current > > configurations. > > UUID can easily be made unique. XFS for example refuses to mount > filesystems with duplicate UUIDs. > In the email from Ted that I referred to he identified two cases where UUIDs are not unique. Are you suggesting that we should cause those use-cases - which work today - to fail? NeilBrown