Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752225AbbHEIxZ (ORCPT ); Wed, 5 Aug 2015 04:53:25 -0400 Received: from mail-io0-f174.google.com ([209.85.223.174]:35239 "EHLO mail-io0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751530AbbHEIxW (ORCPT ); Wed, 5 Aug 2015 04:53:22 -0400 MIME-Version: 1.0 In-Reply-To: <20150805084826.GA23169@gmail.com> References: <1437354550-25858-1-git-send-email-brgerst@gmail.com> <1437354550-25858-5-git-send-email-brgerst@gmail.com> <20150721071151.GA8367@gmail.com> <20150805084826.GA23169@gmail.com> Date: Wed, 5 Aug 2015 10:53:22 +0200 X-Google-Sender-Auth: XU0Z2qIiw-n4sfYt28UkE4PDmw4 Message-ID: Subject: Re: [PATCH 4/7] x86/vm86: Move vm86 fields out of thread_struct From: Linus Torvalds To: Ingo Molnar Cc: Brian Gerst , "the arch/x86 maintainers" , Linux Kernel Mailing List , "H. Peter Anvin" , Denys Vlasenko , Andy Lutomirski Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1041 Lines: 24 On Wed, Aug 5, 2015 at 10:48 AM, Ingo Molnar wrote: >> >> Some of these field names are visible to userspace and can't change. > > That's a misconception: bits in the uapi headers can be renamed just fine. I disagree. If it causes pain for user space, we just shouldn't do it. Some people copy the headers (preferred), others include the kernel header directory with a include path or a symlink, and it's damn painful if we start changing things that user space depends on. I'd say that it's like the ABI - if people don't really notice, you can do it, but if it breaks the build of a user app, we should be very very careful. The breakage is often hard to fix because of nasty versioning issues.. Our goal in life really is "don't screw up user space". Linus -- 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/