From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21998 invoked by alias); 3 Dec 2009 16:57:38 -0000 Received: (qmail 21986 invoked by uid 22791); 3 Dec 2009 16:57:37 -0000 X-SWARE-Spam-Status: No, hits=-2.5 required=5.0 tests=AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from smtp-outbound-2.vmware.com (HELO smtp-outbound-2.vmware.com) (65.115.85.73) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Thu, 03 Dec 2009 16:57:31 +0000 Received: from mailhost3.vmware.com (mailhost3.vmware.com [10.16.27.45]) by smtp-outbound-2.vmware.com (Postfix) with ESMTP id 8474F56071; Thu, 3 Dec 2009 08:57:30 -0800 (PST) Received: from [10.20.94.141] (msnyder-server.eng.vmware.com [10.20.94.141]) by mailhost3.vmware.com (Postfix) with ESMTP id 79528CD91E; Thu, 3 Dec 2009 08:57:30 -0800 (PST) Message-ID: <4B17EE0D.6010702@vmware.com> Date: Thu, 03 Dec 2009 16:57:00 -0000 From: Michael Snyder User-Agent: Thunderbird 1.5.0.12 (X11/20090624) MIME-Version: 1.0 To: Sean Chen CC: Hui Zhu , "gdb@sourceware.org" Subject: Re: System call support in reversible debugging References: <5e81cb500911262231g57f693dwc885576172e016e1@mail.gmail.com> <5e81cb500911270711wb99d531i111d064f05ef03b4@mail.gmail.com> <5e81cb500911270742j546062f2jca7441a912ffad87@mail.gmail.com> <4B10154F.7070902@vmware.com> <5e81cb500911271745t1a119520l4944919d2139e8ae@mail.gmail.com> <4B11607C.7000500@vmware.com> <5e81cb500911300539r52e8be5dva54d32c734978021@mail.gmail.com> <4B142C54.7070207@vmware.com> <5e81cb500912021857i3b0d8f42rde841973757b2d48@mail.gmail.com> In-Reply-To: <5e81cb500912021857i3b0d8f42rde841973757b2d48@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org X-SW-Source: 2009-12/txt/msg00025.txt.bz2 Sean Chen wrote: > On Tue, Dec 1, 2009 at 4:34 AM, Michael Snyder wrote: >> Not a black box -- but not a detailed implementation either. >> Each system call has a specification -- that's all we need to >> understand. The specification tells what user-visible external >> side effects can be expected (eg. this buffer will be filled). >> Changes that are internal to the kernel do not concern us. > > Thanks. I understand your concern. Does Linux kernel provide such an > official specification? If so, could you throw me a hint on where to > get it? Since we have all of the side effects, recording the system > calls are feasible and trustable. > >> Sean, this stuff is already implemented and working. >> Why don't you have a look at the existing code in >> linux-record.c? It sounds like you're more than qualified >> to understand it. If you find something that's not working >> correctly, please let us know! ;-) > > I am reading the source and the archive of the mailing list. Do you > have other systematic documents on this technique? Life becomes better > with your help. Thanks. :) Teawater implemented them, I am only reverse-engineering them, like you. Man pages are helpful. ;-)