From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 66276 invoked by alias); 22 Jan 2016 20:05:49 -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 66253 invoked by uid 89); 22 Jan 2016 20:05:49 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=UD:so.1, gdb.gdb, UD:gdb.gdb, gdbgdb 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; Fri, 22 Jan 2016 20:05:48 +0000 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (Postfix) with ESMTPS id AF4B23F3DB for ; Fri, 22 Jan 2016 20:05:46 +0000 (UTC) Received: from host1.jankratochvil.net (ovpn-116-93.ams2.redhat.com [10.36.116.93]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u0MK5hFj018926 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Fri, 22 Jan 2016 15:05:45 -0500 Date: Fri, 22 Jan 2016 20:05:00 -0000 From: Jan Kratochvil To: Pedro Alves Cc: gdb-patches@sourceware.org Subject: Re: [testsuite patch]#2 Fix PR threads/19422 regression + Guile regression [Re: [PATCH+doc] Fix PR threads/19422 - show which thread caused stop] Message-ID: <20160122200542.GA12621@host1.jankratochvil.net> References: <1451950202-18024-1-git-send-email-palves@redhat.com> <5697ABE8.7060705@redhat.com> <20160122173020.GA5946@host1.jankratochvil.net> <20160122173100.GA5990@host1.jankratochvil.net> <56A276EB.1070208@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <56A276EB.1070208@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-IsSubscribed: yes X-SW-Source: 2016-01/txt/msg00583.txt.bz2 On Fri, 22 Jan 2016 19:37:31 +0100, Pedro Alves wrote: > On 01/22/2016 05:31 PM, Jan Kratochvil wrote: > > OK to check-in the fix for both of these problems? > > I think I'm confused -- the first hunk shows that it's > thread 1 that receives the signal; then why do we need > the "thread 1" command? I have looked more at it now and there is a race. The following outputs are from unpatched FSF GDB HEAD: racy case #1: (xgdb) PASS: gdb.gdb/selftest.exp: Set xgdb_prompt ^M Thread 1 "xgdb" received signal SIGINT, Interrupt.^M 0x00007ffff583bfdd in poll () from /lib64/libc.so.6^M (gdb) FAIL: gdb.gdb/selftest.exp: send ^C to child process signal SIGINT^M Continuing with signal SIGINT.^M ^C^M Thread 1 "xgdb" received signal SIGINT, Interrupt.^M 0x00007ffff5779da0 in sigprocmask () from /lib64/libc.so.6^M (gdb) PASS: gdb.gdb/selftest.exp: send SIGINT signal to child process backtrace^M #0 0x00007ffff5779da0 in sigprocmask () from /lib64/libc.so.6^M #1 0x0000000000704e79 in _rl_handle_signal (sig=2) at signals.c:228^M #2 ^M #3 0x00007ffff583bfdd in poll () from /lib64/libc.so.6^M #4 0x00000000005ebf53 in gdb_wait_for_event (block=block@entry=1) at event-loop.c:746^M #5 0x00000000005ec589 in gdb_do_one_event () at event-loop.c:323^M #6 0x00000000005ec6be in start_event_loop () at event-loop.c:347^M #7 0x00000000005e6513 in captured_command_loop (data=data@entry=0x0) at main.c:318^M #8 0x00000000005e348d in catch_errors (func=func@entry=0x5e6500 , func_args=func_args@entry=0x0, errstring=errstring@entry=0x7e0e6c "", mask=mask@entry=RETURN_MASK_ALL) at exceptions.c:240^M #9 0x00000000005e7006 in captured_main (data=data@entry=0x7fffffffd5f0) at main.c:1157^M #10 0x00000000005e348d in catch_errors (func=func@entry=0x5e6970 , func_args=func_args@entry=0x7fffffffd5f0, errstring=errstring@entry=0x7e0e6c "", mask=mask@entry=RETURN_MASK_ALL) at exceptions.c:240^M #11 0x00000000005e78cb in gdb_main (args=args@entry=0x7fffffffd5f0) at main.c:1165^M #12 0x000000000046c0a5 in main (argc=, argv=) at gdb.c:32^M (gdb) PASS: gdb.gdb/selftest.exp: backtrace through signal handler racy case #2: (xgdb) PASS: gdb.gdb/selftest.exp: Set xgdb_prompt ^M Thread 1 "xgdb" received signal SIGINT, Interrupt.^M 0x00007ffff583bfdd in poll () from /lib64/libc.so.6^M (gdb) FAIL: gdb.gdb/selftest.exp: send ^C to child process signal SIGINT^M Continuing with signal SIGINT.^M ^C^M Thread 2 "xgdb" received signal SIGINT, Interrupt.^M [Switching to Thread 0x7ffff3b7f700 (LWP 13227)]^M 0x00007ffff6b88b10 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0^M (gdb) PASS: gdb.gdb/selftest.exp: send SIGINT signal to child process backtrace^M #0 0x00007ffff6b88b10 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0^M #1 0x00007ffff6db32b7 in GC_wait_marker () from /lib64/libgc.so.1^M #2 0x00007ffff6da92ba in GC_help_marker () from /lib64/libgc.so.1^M #3 0x00007ffff6db15ef in GC_mark_thread () from /lib64/libgc.so.1^M #4 0x00007ffff6b8360a in start_thread () from /lib64/libpthread.so.0^M #5 0x00007ffff5847a4d in clone () from /lib64/libc.so.6^M (gdb) FAIL: gdb.gdb/selftest.exp: backtrace through signal handler Jan