From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 8671 invoked by alias); 16 Sep 2014 12:05:54 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 8661 invoked by uid 89); 16 Sep 2014 12:05:53 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.1 required=5.0 tests=AWL,BAYES_00 autolearn=ham version=3.3.2 X-HELO: relay1.mentorg.com Received: from relay1.mentorg.com (HELO relay1.mentorg.com) (192.94.38.131) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Tue, 16 Sep 2014 12:05:52 +0000 Received: from svr-orw-fem-06.mgc.mentorg.com ([147.34.97.120]) by relay1.mentorg.com with esmtp id 1XTrW1-0005fH-CE from Luis_Gustavo@mentor.com ; Tue, 16 Sep 2014 05:05:49 -0700 Received: from [172.30.12.157] (147.34.91.1) by SVR-ORW-FEM-06.mgc.mentorg.com (147.34.97.120) with Microsoft SMTP Server id 14.3.181.6; Tue, 16 Sep 2014 05:05:48 -0700 Message-ID: <5418279A.1040604@codesourcery.com> Date: Tue, 16 Sep 2014 12:05:00 -0000 From: Luis Machado Reply-To: User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: Joel Brobecker , Yao Qi CC: Subject: Re: [RFA/commit] arm-tdep.c: Do not single-step after hitting a watchpoint. References: <1410786062-19274-1-git-send-email-brobecker@adacore.com> <87bnqf2578.fsf@codesourcery.com> <20140916115936.GM4871@adacore.com> In-Reply-To: <20140916115936.GM4871@adacore.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes X-SW-Source: 2014-09/txt/msg00530.txt.bz2 On 09/16/2014 08:59 AM, Joel Brobecker wrote: >> Can you elaborate your experiments? Do you do experiments on qemu, arm >> bare metal targets or arm linux targets? > > My experiments were on QEMU, but others tried on bare-metal. I tried > on GNU/Linux targets as well, but hardware watchpoints simply did > not work (no signal). > >> I find Peter tries to fix the same problem we encounter in qemu side, >> >> [Qemu-devel] [PATCH] gdbstub: Allow target CPUs to specify watchpoint STOP_BEFORE_ACCESS flag >> http://lists.nongnu.org/archive/html/qemu-devel/2014-09/msg02665.html >> >> and this patch isn't accepted yet. > [...] >> Note that with patched qemu, two fails in gdb.base/recurse.exp are >> fixed. At least, gdb and qemu should be in sync on this. > > I think the experiments that were run showed that QEMU is in fact > correct and should NOT be changed. > Do we know what the Linux kernel's behavior on this one is? I wonder what the stopped data address shows. Someone with access to a board with a relatively new kernel could try that and rule it out, otherwise we risk fixing something for QEMU/bare metal and breaking things for Linux. Luis