From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755114Ab2KWRml (ORCPT ); Fri, 23 Nov 2012 12:42:41 -0500 Received: from mx1.redhat.com ([209.132.183.28]:45126 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753474Ab2KWRmk (ORCPT ); Fri, 23 Nov 2012 12:42:40 -0500 Date: Fri, 23 Nov 2012 18:42:56 +0100 From: Oleg Nesterov To: Pavel Emelyanov Cc: Amnon Shiloh , Cyrill Gorcunov , Steven Rostedt , Frederic Weisbecker , Ingo Molnar , Peter Zijlstra , linux-kernel@vger.kernel.org Subject: Re: vdso && cr (Was: arch_check_bp_in_kernelspace: fix the range check) Message-ID: <20121123174256.GA3361@redhat.com> References: <20121121141627.GB21030@redhat.com> <20121121173043.F0319592076@miso.sublimeip.com> <20121122161238.GA27078@redhat.com> <50AE91AD.1090709@parallels.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <50AE91AD.1090709@parallels.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/23, Pavel Emelyanov wrote: > > On 11/22/2012 08:12 PM, Oleg Nesterov wrote: > > > Sure. You shouldn't try to save/restore this page(s) directly. But > > I do not really understand why do you need. IOW, I don't really > > understand the problem, it depends on what c/r actually does. > > Think about it like this -- you stop a process, then change the kern^w VDSO > page. Everything should work as it used to be :) I understand. But again, this depends on how you restore. For example, if you do not "transfer" libc/ld code, then probably vdso is not a problem. Just you need to ensure the task was not stopped "inside" vdso. Yes, yes, I understand that this is too limited, you probably want to transfer "everything". Oleg.