From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49132) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YV7HJ-0005kV-Cu for qemu-devel@nongnu.org; Mon, 09 Mar 2015 19:40:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YV7HG-0007N5-7b for qemu-devel@nongnu.org; Mon, 09 Mar 2015 19:40:05 -0400 Received: from e34.co.us.ibm.com ([32.97.110.152]:60228) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YV7HG-0007Ks-0X for qemu-devel@nongnu.org; Mon, 09 Mar 2015 19:40:02 -0400 Received: from /spool/local by e34.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 9 Mar 2015 17:40:01 -0600 Received: from b03cxnp08025.gho.boulder.ibm.com (b03cxnp08025.gho.boulder.ibm.com [9.17.130.17]) by d03dlp02.boulder.ibm.com (Postfix) with ESMTP id C5A953E4003B for ; Mon, 9 Mar 2015 17:39:58 -0600 (MDT) Received: from d03av04.boulder.ibm.com (d03av04.boulder.ibm.com [9.17.195.170]) by b03cxnp08025.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t29Ndq4F32702478 for ; Mon, 9 Mar 2015 16:39:52 -0700 Received: from d03av04.boulder.ibm.com (loopback [127.0.0.1]) by d03av04.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t29NdXEX028339 for ; Mon, 9 Mar 2015 17:39:34 -0600 Message-ID: <54FE2F24.6030803@linux.vnet.ibm.com> Date: Mon, 09 Mar 2015 19:39:16 -0400 From: Stefan Berger MIME-Version: 1.0 References: <54FE0A96.30907@linux.vnet.ibm.com> <54FE11E6.3060904@de.ibm.com> In-Reply-To: <54FE11E6.3060904@de.ibm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] Crash when using -daemonize List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Christian Borntraeger , qemu-devel , Paolo Bonzini , Peter Maydell On 03/09/2015 05:34 PM, Christian Borntraeger wrote: > Am 09.03.2015 um 22:03 schrieb Stefan Berger: >> Since an upgrade to Fedora 21, I get crashes with QEMU when using -daemonize. I noticed this since libvirt could not QMP probe QEMU. >> >> This is the command line used: >> >> x86_64-softmmu/qemu-system-x86_64 -S -no-user-config -nodefaults -nographic -M none -pidfile /tmp/foo -daemonize >> >> Here's the backtrace from the coredump: >> >> #0 0x00007fe653d5c8d7 in __GI_raise (sig=sig@entry=6) >> at ../sysdeps/unix/sysv/linux/raise.c:55 >> #1 0x00007fe653d5e53a in __GI_abort () at abort.c:89 >> #2 0x00007fe658c4cb80 in error_exit (err=, >> msg=msg@entry=0x7fe658f58580 <__func__.6036> "qemu_mutex_unlock") >> at util/qemu-thread-posix.c:48 >> #3 0x00007fe658edcab0 in qemu_mutex_unlock ( >> mutex=mutex@entry=0x7fe6593a01c0 ) >> at util/qemu-thread-posix.c:93 >> #4 0x00007fe658c7a96c in qemu_mutex_unlock_iothread () >> at /root/qemu/qemu-git.pt/cpus.c:1137 >> #5 0x00007fe658e7695f in os_host_main_loop_wait (timeout=-1) >> at main-loop.c:234 >> #6 main_loop_wait (nonblocking=) at main-loop.c:494 >> #7 0x00007fe658c4e82e in main_loop () at vl.c:1795 >> #8 main (argc=, argv=, envp=) >> at vl.c:4354 >> >> I am using today's tip of the QEMU git tree, but I don't think that's the actual problem. > I think it is. > Paolo has posted a quick fix in the thread of "vl: take iothread lock very early". > > Can you verify? Yes, verified. And this solves this problem. Stefan