From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754206AbbAEUmX (ORCPT ); Mon, 5 Jan 2015 15:42:23 -0500 Received: from mga14.intel.com ([192.55.52.115]:10472 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752802AbbAEUmW (ORCPT ); Mon, 5 Jan 2015 15:42:22 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.04,691,1406617200"; d="scan'208";a="507772112" From: Andi Kleen To: Dave Hansen Cc: Andy Lutomirski , linux-kernel@vger.kernel.org, x86@kernel.org, Thomas Gleixner Subject: Re: [PATCH 3.19 3/3] x86, mpx: Change the MPX enable/disable API to arch_prctl References: <54A64E6D.1020304@linux.intel.com> Date: Mon, 05 Jan 2015 12:42:08 -0800 In-Reply-To: <54A64E6D.1020304@linux.intel.com> (Dave Hansen's message of "Thu, 01 Jan 2015 23:53:17 -0800") Message-ID: <87mw5x0xjz.fsf@tassilo.jf.intel.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Dave Hansen writes: > On 12/29/2014 04:52 PM, Andy Lutomirski wrote: >> This has the benefit the it avoids cluttering prctl with more >> arch-specific functionality. The down side is that arch_prctl will >> need to be wired up as a 32-bit syscall to add 32-bit support for >> MPX. > > There is existing userspace out there which depends on the existing > prctl() setup. There isn't a _lot_ and it might still be able to be > changed easily, but this isn't a given. > > I'll check in with the folks doing the gcc (runtime) part of this next > week and see what they think. It'll be quite messy for 32bit because they would need to use syscall(), as glibc won't have a arch_prctl stub. -Andi -- ak@linux.intel.com -- Speaking for myself only