Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750962AbdIKHgV (ORCPT ); Mon, 11 Sep 2017 03:36:21 -0400 Received: from bombadil.infradead.org ([65.50.211.133]:50874 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750789AbdIKHgT (ORCPT ); Mon, 11 Sep 2017 03:36:19 -0400 Date: Mon, 11 Sep 2017 00:36:16 -0700 From: Christoph Hellwig To: Kees Cook Cc: Christoph Hellwig , Tycho Andersen , LKML , Linux-MM , "kernel-hardening@lists.openwall.com" , Marco Benatto , Juerg Haefliger , "linux-arm-kernel@lists.infradead.org" , "x86@kernel.org" Subject: Re: [PATCH v6 10/11] mm: add a user_virt_to_phys symbol Message-ID: <20170911073616.GA23201@infradead.org> References: <20170907173609.22696-1-tycho@docker.com> <20170907173609.22696-11-tycho@docker.com> <20170908075519.GD4957@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.8.3 (2017-05-23) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 746 Lines: 16 On Fri, Sep 08, 2017 at 08:44:22AM -0700, Kees Cook wrote: > On Fri, Sep 8, 2017 at 12:55 AM, Christoph Hellwig wrote: > > On Thu, Sep 07, 2017 at 11:36:08AM -0600, Tycho Andersen wrote: > >> We need someting like this for testing XPFO. Since it's architecture > >> specific, putting it in the test code is slightly awkward, so let's make it > >> an arch-specific symbol and export it for use in LKDTM. > > > > We really should not add an export for this. > > > > I think you'll want to just open code it in your test module. > > Isn't that going to be fragile? Why not an export? It is a little fragile, but it is functionality not needed at all by the kernel, so we should not add it to the kernel image and/or export it.