From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751818Ab1FPGgF (ORCPT ); Thu, 16 Jun 2011 02:36:05 -0400 Received: from cantor2.suse.de ([195.135.220.15]:54289 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750731Ab1FPGgB (ORCPT ); Thu, 16 Jun 2011 02:36:01 -0400 Date: Thu, 16 Jun 2011 08:35:58 +0200 From: Michal Hocko To: Linus Torvalds Cc: Andrew Morton , Randy Dunlap , Linux Kernel Mailing List , Richard Weinberger Subject: Re: fs/exec.c: use BUILD_BUG_ON for VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP Message-ID: <20110616063558.GA9840@tiehlicka.suse.cz> References: <201106160359.p5G3x3j4020081@hera.kernel.org> <20110615213549.9b399976.randy.dunlap@oracle.com> <20110615215207.ba7a0386.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110615215207.ba7a0386.akpm@linux-foundation.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed 15-06-11 21:52:07, Andrew Morton wrote: > On Wed, 15 Jun 2011 21:45:00 -0700 Linus Torvalds wrote: > > > On Wed, Jun 15, 2011 at 9:35 PM, Randy Dunlap wrote: > > > > > > fwiw, I just reported that this causes a build error in UML on x86_64 > > > in mmotm-2011-06-15: > > > > Gaah. That sounds really familiar. Have we done this same mistake once > > before already, or is it just deja-vu for some other reason. > > > > On x86-64 UML, we have > > > > #define VM_STACK_DEFAULT_FLAGS vm_stack_flags > > > > so VM_STACK_FLAGS ends up not being a constant, even though it really > > looks like one. > > > > UML is _really_ confused in this area, btw. It seems to re-define that > > thing if TIF_IA32 is defined. That's some crazy stuff. Doesn't the > > compiler warn about it? > > > > I guess I should just revert that commit, though. Even if it does seem > > to be the case that UML is just being crazy. Andrew? > > > > Sure, it was just a tiny optimization. Please revert and sorry for this. -- Michal Hocko SUSE Labs SUSE LINUX s.r.o. Lihovarska 1060/12 190 00 Praha 9 Czech Republic