From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754489AbaJ1Rqj (ORCPT ); Tue, 28 Oct 2014 13:46:39 -0400 Received: from relay3-d.mail.gandi.net ([217.70.183.195]:46799 "EHLO relay3-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750855AbaJ1Rqi (ORCPT ); Tue, 28 Oct 2014 13:46:38 -0400 Date: Tue, 28 Oct 2014 10:46:33 -0700 From: josh@joshtriplett.org To: Andy Lutomirski Cc: x86@kernel.org, linux-kernel@vger.kernel.org, mingo@kernel.org Subject: Re: [PATCH 0/3] x86_64: Tidy up vsyscall emulation and make it optional Message-ID: <20141028174633.GB12195@cloud> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 28, 2014 at 10:22:25AM -0700, Andy Lutomirski wrote: > Now that arch/x86/kernel/vsyscall_64.c contains only vsyscall > emulation code, clean it up and make it optional. > > Patch 1 makes vsyscall=none work be a bit more self-consistent: it > actually removes the fake vsyscall page instead of just segfaulting > anyone who tries to use it. > > Patch 2 is pure cosmetic cleanup. > > Patch 3 is the meat: it lets vsyscall emulation be configured out. > The config option to disable it is hidden under CONFIG_EXPERT, since > it will break legacy code. > > Note that, last I checked, current userspace is unlikely to work if > the vDSO *and* vsyscalls are off. Take it up with the glibc > maintainers. > > This applies on top of tip/x86/vdso. > > Andy Lutomirski (3): > x86_64,vsyscall: Turn vsyscalls all the way off when vsyscall=none > x86_64,vsyscall: Rewrite comment and clean up headers in vsyscall code > x86_64,vsyscall: Make vsyscall emulation configurable Nice! For patches 1 and 2: Reviewed-by: Josh Triplett For patch 3, I responded with a possible minor improvement, but with or without that: Reviewed-by: Josh Triplett I assume these should go through tip/x86/vdso as well? Also, any plans to do something similar for vsyscall_gtod.c? - Josh Triplett