From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 1712 invoked by alias); 24 Apr 2015 07:39:21 -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 1694 invoked by uid 89); 24 Apr 2015 07:39:20 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.4 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=ham version=3.3.2 X-HELO: mail-pd0-f182.google.com Received: from mail-pd0-f182.google.com (HELO mail-pd0-f182.google.com) (209.85.192.182) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-GCM-SHA256 encrypted) ESMTPS; Fri, 24 Apr 2015 07:39:19 +0000 Received: by pdbqd1 with SMTP id qd1so41682870pdb.2 for ; Fri, 24 Apr 2015 00:39:17 -0700 (PDT) X-Received: by 10.67.8.98 with SMTP id dj2mr12387988pad.79.1429861157644; Fri, 24 Apr 2015 00:39:17 -0700 (PDT) Received: from E107787-LIN (gcc1-power7.osuosl.org. [140.211.15.137]) by mx.google.com with ESMTPSA id by13sm10191725pdb.37.2015.04.24.00.39.15 (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Fri, 24 Apr 2015 00:39:16 -0700 (PDT) From: Yao Qi To: Pedro Alves Cc: Yao Qi , gdb-patches@sourceware.org Subject: Re: [PATCH v3 10/17] Implement all-stop on top of a target running non-stop mode References: <1429267521-21047-1-git-send-email-palves@redhat.com> <1429267521-21047-11-git-send-email-palves@redhat.com> <86a8y1zqkd.fsf@gmail.com> <5538017B.9040907@redhat.com> Date: Fri, 24 Apr 2015 07:39:00 -0000 In-Reply-To: <5538017B.9040907@redhat.com> (Pedro Alves's message of "Wed, 22 Apr 2015 21:15:55 +0100") Message-ID: <86h9s6x9eo.fsf@gmail.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-IsSubscribed: yes X-SW-Source: 2015-04/txt/msg00927.txt.bz2 Pedro Alves writes: >> This path is about the case that a signal is got while in in-line >> stepping, isn't? If so, non_stop should be an invariant false. We >> don't need to check it. > > Hmm, not sure what you mean: > Let me ask it in another way, when we get here, it means a signal arrived, the code some lines above is: if (debug_infrun) fprintf_unfiltered (gdb_stdlog, "infrun: signal arrived while stepping over= " "breakpoint\n"); GDB just did the breakpoint step over, via in-line stepping or out-of-line stepping, right? as your patch below shows. > - We need to do this with displaced stepping too, because we can't > deliver signals while doing a displaced step. See comments at the > top of displaced_step_prepare and in do_target_resume. The first sentence is contradictory, or you mean we *can* do either out-of-line stepping or in-line stepping, but we can't deliver a signal while doing a displaced stepping... > > - We can certainly get a signal while doing an in-line step-over. > The simplest would be, trying to step-over a breakpoint here: > > *(volatile int *)0 =3D 1; > > which usually results SIGSEGV. ... while we can deliver a signal in in-line stepping. Is it correct? --=20 Yao (=E9=BD=90=E5=B0=A7)