Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758384AbbGHTNq (ORCPT ); Wed, 8 Jul 2015 15:13:46 -0400 Received: from mail-wi0-f178.google.com ([209.85.212.178]:37449 "EHLO mail-wi0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754594AbbGHTNi (ORCPT ); Wed, 8 Jul 2015 15:13:38 -0400 Date: Wed, 8 Jul 2015 21:13:33 +0200 From: Ingo Molnar To: Linus Torvalds Cc: Arjan van de Ven , Andy Lutomirski , the arch/x86 maintainers , Linux Kernel Mailing List , Oleg Nesterov , Kees Cook , Peter Zijlstra , Borislav Petkov Subject: Re: [PATCH] x86/kconfig/32: Mark CONFIG_VM86 as BROKEN Message-ID: <20150708191333.GA26746@gmail.com> References: <23d4709cee2fe92c32d41b99c7a3c1823725925a.1436312944.git.luto@kernel.org> <559C8BFE.6050604@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1604 Lines: 36 * Linus Torvalds wrote: > On Tue, Jul 7, 2015 at 7:33 PM, Arjan van de Ven wrote: > > > > if this patch would not be acceptable, at minimum we need some sort of "off by > > default unless the sysadmin flips a sysfs thing", which is really just a huge > > hack. > > The only thing that matters is whether people use this or not. > > If people use vm86 mode, we can't just disable it. It's that simple. "It's > poorly maintained" isn't an argument for removal. Only "nobody cares" works as > an argument for that. > > My suspicion is that people still do use vm86 mode, but who knows.. Quite > frankly, rather than disable it, I'd much rather see people who modify low-level > x86 code (yes, that means you, Luto) *test* it. If you aren't willign to test > the modifications you make, I don't think those modifications should be merged, > regardless of how nice a cleanup they are. The dosemu case might just work due to emulation (assuming emulation is equivalent or better than vm86 mode), but if Xorg still uses vm86 on old systems to run the Video-BIOS, with no fallback code available, then I doubt we can remove it. In any case it's a lot less clear-cut than I initially thought, so I've removed the patch until it's determined whether it's still used by anything. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/