From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 95109 invoked by alias); 8 Jan 2018 16:35:00 -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 95090 invoked by uid 89); 8 Jan 2018 16:34:59 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-0.9 required=5.0 tests=BAYES_00,KAM_LAZY_DOMAIN_SECURITY,SPF_HELO_PASS,T_RP_MATCHES_RCVD autolearn=no version=3.3.2 spammy=Hx-languages-length:1423, HTo:U*macro X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Mon, 08 Jan 2018 16:34:58 +0000 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id BE39046661; Mon, 8 Jan 2018 16:34:56 +0000 (UTC) Received: from [127.0.0.1] (ovpn04.gateway.prod.ext.ams2.redhat.com [10.39.146.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id F08195C1A1; Mon, 8 Jan 2018 16:34:54 +0000 (UTC) Subject: Re: GDB 8.1 release -- 2018-01-08 update To: "Maciej W. Rozycki" , Joel Brobecker References: <20180108074937.fq44jr4qkdphgeew@adacore.com> Cc: gdb-patches@sourceware.org, "Maciej W. Rozycki" , tom@tromey.com, simon.marchi@ericsson.com From: Pedro Alves Message-ID: <77539a17-7418-86ac-09b0-bb68650a610d@redhat.com> Date: Mon, 08 Jan 2018 16:35:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-SW-Source: 2018-01/txt/msg00166.txt.bz2 On 01/08/2018 09:54 AM, Maciej W. Rozycki wrote: > Hi Joel, > >> * [Maciej] remote/22597 >> Empty `qsThreadInfo' reply handling regression causing inability to execute >> >> I'm trying to understand whether this is specific to mips or more >> general. And whether this only affects GDB when debugging with older >> stubs or whether it affects us more generally. >> >> Depending on the answer, the issue might not be so severe as >> to hold the release. >> >> Maciej - can you tell where we are on this issue, and whether >> you think it really is blocking for 8.1? > > GDB uses the special thread ID 0, standing for `any', which older > `gdbserver' versions do not recognise. It does not verify beforehand > whether `gdbserver' supports this request and does not handle an error > reply gracefully. Consequently an error reply to a `Hg0' packet issued > causes GDB to lose track of what is going on, making it impossible to > continue with the debug session. This happens with all sessions in the > initial connection handshake, making the combination of new GDB and old > `gdbserver' unusable. I'm looking at this. I can reproduce it on x86-64 using a gdbserver from 2007 (git hash "f8b73d13b7ca^", the same revision Maciej's gdbserver is built from). I confirm that 5cd63fda035d somehow introduces the regression. No idea why yet. So not specific to MIPS. Thanks, Pedro Alves