From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759493AbZEGJPz (ORCPT ); Thu, 7 May 2009 05:15:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755537AbZEGJPp (ORCPT ); Thu, 7 May 2009 05:15:45 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:41152 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754385AbZEGJPo (ORCPT ); Thu, 7 May 2009 05:15:44 -0400 Date: Thu, 7 May 2009 11:13:57 +0200 From: Ingo Molnar To: Roland McGrath , "K.Prasad" , Alan Stern Cc: Alexey Dobriyan , Oleg Nesterov , akpm@linux-foundation.org, linux-kernel@vger.kernel.org, containers@lists.linux-foundation.org Subject: Re: [PATCH] x86: ptrace debugreg checks rewrite Message-ID: <20090507091357.GA26433@elte.hu> References: <20090504001601.GL16631@x200.localdomain> <20090504002431.GA17556@x200.localdomain> <20090506095629.GC15323@elte.hu> <20090506203852.D9AC9FC39E@magilla.sf.frob.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090506203852.D9AC9FC39E@magilla.sf.frob.com> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Roland McGrath wrote: > > > On Mon, May 04, 2009 at 04:16:01AM +0400, Alexey Dobriyan wrote: > > > > +static int ptrace_check_debugreg(int _32bit, > > > > + unsigned long dr0, unsigned long dr1, > > > > + unsigned long dr2, unsigned long dr3, > > > > + unsigned long dr6, unsigned long dr7) > > > > +{ > > > > + /* Breakpoint type: 00: --x, 01: -w-, 10: undefined, 11: rw- */ > > > > + unsigned int rw[4]; > > > > + /* Breakpoint length: 00: 1 byte, 01: 2 bytes, 10: 8 bytes, 11: bytes */ > > > 4 bytes, of course > > > > Roland, Oleg, do you have any pending/planned changes in this area? > > I don't. I expect the only future work on this arch debugreg > stuff to be via the hw_breakpoint work, extending that and/or > building new things on it. Yes. That work, despite being in its upteenth iteration, is taking a frustratingly long amount of time to get even to a minimal "review passed, lets commit and test this in a tree a bit" intermediate stage though. I've Cc:-ed K.Prasad and Alan Stern. Roland, Oleg, would you be interested in having a look at that thread, to help drive it forward? The last iteration was posted to lkml on Apr 24: [Patch 00/12] Hardware Breakpoint Interfaces and it has a good deal of ptrace, signal handling and other impact as well. Ingo