From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Torvalds Subject: Re: [PATCH] vfs: automount should ignore LOOKUP_FOLLOW Date: Thu, 8 Sep 2011 10:42:28 -0700 Message-ID: References: <87liu37z3x.fsf@tucsk.pomaz.szeredi.hu> <17416.1315240659@redhat.com> <87hb4q9b3r.fsf@tucsk.pomaz.szeredi.hu> <1315281208.3210.26.camel@perseus.themaw.net> <87mxeixfaq.fsf@tucsk.pomaz.szeredi.hu> <1315319903.3210.51.camel@perseus.themaw.net> <87ipp5y912.fsf@tucsk.pomaz.szeredi.hu> <1315485406.3476.9.camel@perseus.themaw.net> <87bouv17dc.fsf@tucsk.pomaz.szeredi.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Ian Kent , David Howells , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Leonardo Chiquitto , Al Viro , autofs@linux.kernel.org To: Miklos Szeredi Return-path: In-Reply-To: <87bouv17dc.fsf@tucsk.pomaz.szeredi.hu> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Thu, Sep 8, 2011 at 6:38 AM, Miklos Szeredi wrot= e: > > Yes, 2.6.38 and later kernels do trigger on stat(2) but not on lstat(= 2). > > My question is this: =A0does this behavior improve anything compared = to > kernels before 2.6.38? =A0Because I don't see that it does, in fact i= t's > just causing regressions. > > You say it's a step in the right direction but I don't see why. =A0Ei= ther > we want stat *and* lstat to both be correct and trigger the automount= or > we are satisfied with the incorrect but well established practice of = not > triggering on (l)stat. > > The middle ground makes no sense IMO, there's nothing gained by the > differentiated behavior based on LOOKUP_FOLLOW. > > Can you explain why it's better if stat() tiggers automounts and give= s a > correct result but lstat() doesn't? I have to say that this is a very cogent question. The one thing I've not seen in the thread yet is a description of the failure. What does the regression look like? Just "very slow 'ls' with some versions of 'ls'" or what? I'm inclined to apply the patch as a regression fix, but I'll let this thread try to convince me for another day.. Linus