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[209.132.180.67]) by mx.google.com with ESMTP id b184-v6si13007590pfg.94.2018.07.30.14.42.07; Mon, 30 Jul 2018 14:42:21 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731914AbeG3XSJ (ORCPT + 99 others); Mon, 30 Jul 2018 19:18:09 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:54256 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726872AbeG3XSJ (ORCPT ); Mon, 30 Jul 2018 19:18:09 -0400 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.87 #1 (Red Hat Linux)) id 1fkFuf-0007hp-5j; Mon, 30 Jul 2018 21:41:09 +0000 Date: Mon, 30 Jul 2018 22:41:09 +0100 From: Al Viro To: Christian Brauner Cc: Matthew Wilcox , Christoph Hellwig , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, arve@android.com, tkjos@android.com, maco@android.com, rlove@google.com, ben@decadent.org.uk Subject: Re: [RFC PATCH 0/4] file: export functions for binder module Message-ID: <20180730214108.GE30522@ZenIV.linux.org.uk> References: <20180730143710.14413-1-christian@brauner.io> <20180730163452.GE27761@infradead.org> <20180730201224.GA1081@mailbox.org> <20180730201947.GB12962@bombadil.infradead.org> <20180730202840.GA14693@mailbox.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180730202840.GA14693@mailbox.org> User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 30, 2018 at 10:28:40PM +0200, Christian Brauner wrote: > On Mon, Jul 30, 2018 at 01:19:47PM -0700, Matthew Wilcox wrote: > > On Mon, Jul 30, 2018 at 10:12:24PM +0200, Christian Brauner wrote: > > > > I don't expect this patch to be mergeable but rather to kick-off a > > > > discussion if we can either simply export them as they are or how we can > > > > get supportable exports that allow access to struct files_struct. > > > > > > Maybe that wasn't obvious from the first message. Is there any way we > > > can come up with a way to have versions of these functions that you > > > would be fine with exporting? > > > The point is that otherwise we would have to either duplicate the code > > > or come up with something way more complex. If you have any pointer that > > > would already help. > > > > He said in the first reply this should probably be using an anonfd. > > If you do that, I think all four of these exports go away. > > I try and see if that is possible. > > > > > And there was really no reason to post each of the four exports as > > separate patches. That just makes review harder on everyone. > > Sorry about that. It usually depends on the preferences of each > maintainer how fine-grained such minor changes should be. The fundamental problem here (besides "who the hell thought that this Fine Piece Of Software belongs anywhere other than in /dev/null?") is that messing with other's descriptor table is Fucking Wrong(tm). It's not going to become a general-purpose interface. That kludge is just that - a kludge caused by atrocious API design. Exports NAKed, and if brought again they'll get NAKed with extreme prejudice (sensu PTerry).