From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Thu, 13 Oct 2016 22:24:04 +0100 From: Al Viro To: Vineeth Remanan Pillai Cc: Christoph Hellwig , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, kamatam@amazon.com, aliguori@amazon.com Subject: Re: [PATCH] namei: revert old behaviour for filename_lookup with LOOKUP_PARENT flag Message-ID: <20161013212404.GU19539@ZenIV.linux.org.uk> References: <1476388731-24053-1-git-send-email-vineethp@amazon.com> <20161013200904.GA23139@infradead.org> <20161013202622.GS19539@ZenIV.linux.org.uk> <5d487c39-25e9-2903-1fd9-ca6d870c0e7b@amazon.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5d487c39-25e9-2903-1fd9-ca6d870c0e7b@amazon.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: On Thu, Oct 13, 2016 at 01:41:11PM -0700, Vineeth Remanan Pillai wrote: > Yes, the use case is out-of-tree and the code snippet above depicts the use > . > Since kern_path_locked is also not exported, out-of-tree code used kern_path > for the existence check for directories. > > One reference about this issue can be seen here. > > http://www.gossamer-threads.com/lists/linux/kernel/2459690?do=post_view_flat#2459690 ... and in that thread I have asked for details and got no reply whatsoever. > We also have a customer who complained about this functionality change. > > I understand that there has been no API promises been made to this API. But > since this is an > exported function, the change in function could cause break in out-of-tree > kernel code. I will > rephrase the commit message to say "change in functionality" instead of > regression In principle, I have no strong objections against exporting kern_path_locked, provided it really matches what they (whoever they are) need. I'm still curious about the context, though - what is that code trying to do? Depending on the actual stuff it wants to implement, there might be better primitives for doing that *and* there might be something worth adding and exporting that would be a better match. It's not that kern_path_locked() isn't a sane interface, but... using it might be a sign of trying to work around something missing in API. So again, please post more details.