From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Torvalds Subject: Re: [PATCH 1/3] autofs4 - fix device ioctl mount lookup Date: Tue, 3 Sep 2013 19:18:42 -0700 Message-ID: References: <20130904005456.5025.94309.stgit@perseus.fritz.box> <20130904010301.GE13318@ZenIV.linux.org.uk> <20130904020013.GF13318@ZenIV.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: Ian Kent , linux-fsdevel , rui.xiang@huawei.com, autofs mailing list , Kernel Mailing List To: Al Viro Return-path: In-Reply-To: <20130904020013.GF13318@ZenIV.linux.org.uk> Sender: autofs-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Tue, Sep 3, 2013 at 7:00 PM, Al Viro wrote: > > That aside, I'm really not happy with this kind of games; this stuff clearly > belongs in fs/namei.c where we can simply see the last component. Doing that > on the level of "let's scan the pathname for slashes, etc." is just plain > wrong. Let's step back for a minute here; what are you trying to do? > You have a pathname that should resolve to a mountpoint, without triggering > automount (or crossing into the mountpoint, for that matter) and you want > struct path for the bottom of that mount stack? Or is it something > completely different? Can we add a LOOKUP_NOAUTOMNT bit or something (not exposed to user space, only used for this particular kern_path() call). Then, if/when automount gets called recursively (through autofs4_lookup? Or is it just the autofs4_d_automount() interface?) it can just decide to not follow that last path. Hmm? I don't think we pass in the lookup-flags to d_automount, but that could be changed. Yes? Linus