From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754598Ab2KZJoJ (ORCPT ); Mon, 26 Nov 2012 04:44:09 -0500 Received: from mail-la0-f46.google.com ([209.85.215.46]:50478 "EHLO mail-la0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753624Ab2KZJoH (ORCPT ); Mon, 26 Nov 2012 04:44:07 -0500 Date: Mon, 26 Nov 2012 13:44:03 +0400 From: Cyrill Gorcunov To: Oleg Nesterov , Amnon Shiloh Cc: Pavel Emelyanov , Steven Rostedt , Frederic Weisbecker , Ingo Molnar , Peter Zijlstra , Andrey Vagin , linux-kernel@vger.kernel.org Subject: Re: vdso && cr (Was: arch_check_bp_in_kernelspace: fix the range check) Message-ID: <20121126094403.GB10312@moon> References: <20121121141627.GB21030@redhat.com> <20121121173043.F0319592076@miso.sublimeip.com> <20121122161238.GA27078@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20121122161238.GA27078@redhat.com> 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 Thu, Nov 22, 2012 at 05:12:38PM +0100, Oleg Nesterov wrote: > On 11/22, Amnon Shiloh wrote: > > > > Now however, that "vsyscall" was effectively replaced by vdso, it > > creates a new problem for me and probably for anyone else who uses > > some form of checkpoint/restore: > > Oh, sorry, I can't help here. I can only add Cyrill and Pavel, they > seem to enjoy trying to solve the c/r problems. Hi Oleg, Amnon, sorry for delay on this message. First of all, I'm not vDSO specialist but as to c/r aspect of it I've had in mind the the following scenario: we dump vDSO area either complete euther simply remember the functions addresses it provides, then on restore we replace the functions prologue with jmp instruction which would point to the vDSO entries provided us by a kernel. But again, I didn't spend much time for vDSO yet. Cyrill