From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 9581 invoked by alias); 22 Dec 2005 03:48:14 -0000 Received: (qmail 9574 invoked by uid 22791); 22 Dec 2005 03:48:14 -0000 X-Spam-Check-By: sourceware.org Received: from ausmtp03.au.ibm.com (HELO ausmtp03.au.ibm.com) (202.81.18.151) by sourceware.org (qpsmtpd/0.31) with ESMTP; Thu, 22 Dec 2005 03:48:13 +0000 Received: from sd0208e0.au.ibm.com (d23rh904.au.ibm.com [202.81.18.202]) by ausmtp03.au.ibm.com (8.12.10/8.12.10) with ESMTP id jBM3pFHd069306 for ; Thu, 22 Dec 2005 14:51:20 +1100 Received: from d23av03.au.ibm.com (d23av03.au.ibm.com [9.190.250.244]) by sd0208e0.au.ibm.com (8.12.10/NCO/VERS6.8) with ESMTP id jBM3p4mc144686 for ; Thu, 22 Dec 2005 14:51:04 +1100 Received: from d23av03.au.ibm.com (loopback [127.0.0.1]) by d23av03.au.ibm.com (8.12.11/8.13.3) with ESMTP id jBM3m0d7015117 for ; Thu, 22 Dec 2005 14:48:00 +1100 Received: from [9.181.133.187] ([9.181.133.187]) by d23av03.au.ibm.com (8.12.11/8.12.11) with ESMTP id jBM3ltgD015028; Thu, 22 Dec 2005 14:47:56 +1100 Date: Thu, 22 Dec 2005 15:26:00 -0000 From: Wu Zhou To: anton@au1.ibm.com cc: drow@false.org, gdb-patches@sources.redhat.com, mark@xs4all.nl, bje@au1.ibm.com Subject: Re: [RFC] GDB patches for hw watchpoints - revised Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-IsSubscribed: yes Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2005-12/txt/msg00256.txt.bz2 > Yeah, we cant assume we have only one data breakpoint register - I think > some of the 32bit cpus have multiple ones. Can you recall which cpus have multiple ones? I am now reading related processor document and find that Book E seems to use a different debug facility. It has three debug control registers, one debug status register, two insruction address compare registers and two data address compare registers (maybe the same as DABR in other POWER/PowerPC arch). That is in <>. So maybe the "at most one DABR" assertion still hold for most ppc arches. And provided that the current kernel only support at most one DABR, so this patch still make sense for GDB, right? Any objection? :-) What is more, in function ppc_linux_check_watch_resources, there is a run time check to see whether the command PTRACE_SET_DEBUGREG of ptrace can succeed. I believe that will make these archs which don't have DABR not impacted by this patch. So I am thinking this patch still make sense. What is your thought? Very happy to know your comments. Regards - Wu Zhou