From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 112833 invoked by alias); 6 Apr 2016 13:49:18 -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 112821 invoked by uid 89); 6 Apr 2016 13:49:17 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.9 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=ham version=3.3.2 spammy= 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 (AES256-GCM-SHA384 encrypted) ESMTPS; Wed, 06 Apr 2016 13:49:16 +0000 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 84D0763170 for ; Wed, 6 Apr 2016 13:49:15 +0000 (UTC) Received: from host1.jankratochvil.net (ovpn-116-59.ams2.redhat.com [10.36.116.59]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u36DnCEa026697 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Wed, 6 Apr 2016 09:49:14 -0400 Date: Wed, 06 Apr 2016 13:49:00 -0000 From: Jan Kratochvil To: Pedro Alves Cc: gdb-patches@sourceware.org, Gary Benson Subject: [patchv4] Workaround gdbserver<7.7 for setfs Message-ID: <20160406134911.GA30545@host1.jankratochvil.net> References: <20160319201842.GA16540@host1.jankratochvil.net> <56F13963.9040204@redhat.com> <20160322131604.GA24312@host1.jankratochvil.net> <56F14F1E.5010606@redhat.com> <20160323211547.GA17400@host1.jankratochvil.net> <20160324220933.GA27445@host1.jankratochvil.net> <20160324223241.GB2548@host1.jankratochvil.net> <56FBDFE7.90203@redhat.com> <20160404211406.GA32241@host1.jankratochvil.net> <5703E7FF.6060304@redhat.com> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="huq684BweRXVnRxX" Content-Disposition: inline In-Reply-To: <5703E7FF.6060304@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-IsSubscribed: yes X-SW-Source: 2016-04/txt/msg00124.txt.bz2 --huq684BweRXVnRxX Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-length: 559 On Tue, 05 Apr 2016 18:29:51 +0200, Pedro Alves wrote: > MustReplyEmpty is actually not a useful probe packet, because > that's actually an M (write memory) packet, which is then > misinterpreted and fails the write. So not an unknown packet. Oops, OK. > Try qMustReplyEmpty or something like that instead. With these requirements on this workaround I have followed the gdbserver-7.6 sources and the bug was in function handle_notif_ack which is called only from handle_v_requests, therefore for any packets /^v/. OK to check in this one? Thanks, Jan --huq684BweRXVnRxX Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="v.patch" Content-length: 2170 gdb/gdbserver/ChangeLog 2016-04-05 Jan Kratochvil * remote.c (unknown_v_replies_ok): New variable. (packet_config_support): Read it. (remote_start_remote): Set it. diff --git a/gdb/remote.c b/gdb/remote.c index 5c407b6..a88f4cd 100644 --- a/gdb/remote.c +++ b/gdb/remote.c @@ -1496,6 +1496,15 @@ enum { static struct packet_config remote_protocol_packets[PACKET_MAX]; +/* gdbserver < 7.7 (before its fix from 2013-12-11) did reply to any + unknown 'v' packet with string "OK". "OK" gets interpreted by GDB + as a reply to known packet. For packet "vFile:setfs:" it is an + invalid reply and GDB would return error in + remote_hostio_set_filesystem, making remote files access impossible. + If this variable is non-zero it means the remote gdbserver is buggy + and any not yet detected packets are assumed as unsupported. */ +static int unknown_v_replies_ok; + /* Returns the packet's corresponding "set remote foo-packet" command state. See struct packet_config for more details. */ @@ -1519,6 +1528,9 @@ packet_config_support (struct packet_config *config) case AUTO_BOOLEAN_FALSE: return PACKET_DISABLE; case AUTO_BOOLEAN_AUTO: + if (unknown_v_replies_ok && config->name != NULL + && config->name[0] == 'v') + return PACKET_DISABLE; return config->support; default: gdb_assert_not_reached (_("bad switch")); @@ -4023,6 +4035,21 @@ remote_start_remote (int from_tty, struct target_ops *target, int extended_p) if (packet_support (PACKET_QAllow) != PACKET_DISABLE) remote_set_permissions (target); + /* See unknown_v_replies_ok description. */ + { + const char v_mustreplyempty[] = "vMustReplyEmpty"; + + putpkt (v_mustreplyempty); + getpkt (&rs->buf, &rs->buf_size, 0); + if (strcmp (rs->buf, "OK") == 0) + unknown_v_replies_ok = 1; + else if (strcmp (rs->buf, "") == 0) + unknown_v_replies_ok = 0; + else + error (_("Remote replied unexpectedly to '%s': %s"), v_mustreplyempty, + rs->buf); + } + /* Next, we possibly activate noack mode. If the QStartNoAckMode packet configuration is set to AUTO, --huq684BweRXVnRxX--