From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755329Ab0BOQP6 (ORCPT ); Mon, 15 Feb 2010 11:15:58 -0500 Received: from mail.codeweavers.com ([216.251.189.131]:34378 "EHLO mail.codeweavers.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752106Ab0BOQP5 (ORCPT ); Mon, 15 Feb 2010 11:15:57 -0500 X-Greylist: delayed 1112 seconds by postgrey-1.27 at vger.kernel.org; Mon, 15 Feb 2010 11:15:56 EST From: Alexandre Julliard To: prasad@linux.vnet.ibm.com Cc: Michael Stefaniuc , Frederic Weisbecker , Alan Stern , linux-kernel@vger.kernel.org, Maneesh Soni , "Rafael J. Wysocki" , Maciej Rutecki , Roland McGrath Subject: Re: Regression in ptrace (Wine) starting with 2.6.33-rc1 References: <4B743149.4000707@redhat.com> <20100211182224.GC4915@nowhere> <4B745F5C.5050001@redhat.com> <20100213173323.GB3778@in.ibm.com> <4B7719AC.6040901@redhat.com> <20100214171535.GA5065@nowhere> <4B785952.8020706@redhat.com> <20100214204130.GD5479@nowhere> <4B7881AC.5070209@redhat.com> <20100215115713.GA8907@in.ibm.com> Date: Mon, 15 Feb 2010 16:57:08 +0100 In-Reply-To: <20100215115713.GA8907@in.ibm.com> (K. Prasad's message of "Mon, 15 Feb 2010 17:27:13 +0530") Message-ID: <87ljeutru3.fsf@wine.dyndns.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.1.92 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Spam-Score: -3.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org "K.Prasad" writes: > We could change this to become 'local' for every local request (but still > cleanup the breakpoints using scheduler hooks like the way we presently > do), but I think this is an implementation detail and that a ptrace user > need not worry about it. Or do you believe that there's any? > > I'm afraid I don't understand your motivation for these read/write tests > on debug control register? Such tests, as in this case, cause unnecessary > panic due to changes in an implementation detail internal to the kernel > without any perceptible difference in functionality. Various copy protection schemes such as Safedisc do all sorts of strange manipulations and checks on the debug registers, in an attempt to make sure that the app is not being run under a debugger. The Wine exception tests try to replicate that behavior. -- Alexandre Julliard julliard@winehq.org