From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756055Ab0BOUoN (ORCPT ); Mon, 15 Feb 2010 15:44:13 -0500 Received: from terminus.zytor.com ([198.137.202.10]:57279 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755467Ab0BOUoM (ORCPT ); Mon, 15 Feb 2010 15:44:12 -0500 Message-ID: <4B79B202.5090006@zytor.com> Date: Mon, 15 Feb 2010 12:43:46 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.7) Gecko/20100120 Fedora/3.0.1-1.fc12 Thunderbird/3.0.1 MIME-Version: 1.0 To: Roland McGrath CC: Oleg Nesterov , Linus Torvalds , linux-kernel@vger.kernel.org Subject: Re: x86: get rid of the insane TIF_ABI_PENDING bit References: <20100215161752.GA19962@redhat.com> <4B799C3F.7010308@zytor.com> <20100215194123.96D49FC3@magilla.sf.frob.com> In-Reply-To: <20100215194123.96D49FC3@magilla.sf.frob.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/15/2010 11:41 AM, Roland McGrath wrote: > It affects whatever uses is_compat_task(), but I can't see anything > where that matters except inside some particular syscall or for > syscall restart after signals. FWIW, the origin of this is checkin 4d9bc79cd28b779610d9590b3a96a28a0f64a25a (2.6.18-rc1), which somewhat unhelpfully states "Make sure is_compat_task works early". It doesn't specify what the failure is if is_compat_task doesn't work early. On the other hand, it sure as heck seems better to set it and not need it than the other way around. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.