From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:59855) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RHscr-00067v-97 for qemu-devel@nongnu.org; Sun, 23 Oct 2011 03:37:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RHscp-0005pn-NT for qemu-devel@nongnu.org; Sun, 23 Oct 2011 03:37:45 -0400 Received: from mx1.redhat.com ([209.132.183.28]:20461) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RHscp-0005pf-GQ for qemu-devel@nongnu.org; Sun, 23 Oct 2011 03:37:43 -0400 Message-ID: <4EA3C457.2060500@redhat.com> Date: Sun, 23 Oct 2011 09:37:59 +0200 From: Yonit Halperin MIME-Version: 1.0 References: <20111021152627.GF23627@redhat.com> In-Reply-To: <20111021152627.GF23627@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [Spice-devel] Possible SPICE/QEMU deadlock on fast client reconnect List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Daniel P. Berrange" Cc: spice-devel@lists.freedesktop.org, qemu-devel@nongnu.org Hi, Sounds like https://bugzilla.redhat.com/show_bug.cgi?id=746950 and https://bugs.freedesktop.org/show_bug.cgi?id=41858 Alon's patch: http://lists.freedesktop.org/archives/spice-devel/2011-September /005369.html Should solve it. Cheers, Yonit. On 10/21/2011 05:26 PM, Daniel P. Berrange wrote: > In testing my patches for 'add_client' support with SPICE, I noticed > deadlock in the QEMU/SPICE code. It only happens if I close a SPICE > client and then immediately reconnect within about 1 second. If I > wait a couple of seconds before reconnecting the SPICE client I don't > see the deadlock. > > I'm using QEMU& SPICE git master, and GDB has this to say > > (gdb) thread apply all bt > > Thread 3 (Thread 0x7f269e142700 (LWP 17233)): > #0 pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:165 > #1 0x00000000004e80e9 in qemu_cond_wait (cond=, mutex=) > at qemu-thread-posix.c:113 > #2 0x0000000000556469 in qemu_kvm_wait_io_event (env=) > at /home/berrange/src/virt/qemu/cpus.c:626 > #3 qemu_kvm_cpu_thread_fn (arg=0x29217a0) at /home/berrange/src/virt/qemu/cpus.c:661 > #4 0x0000003a83207b31 in start_thread (arg=0x7f269e142700) at pthread_create.c:305 > #5 0x0000003a82edfd2d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:115 > > Thread 2 (Thread 0x7f26822fc700 (LWP 17234)): > #0 __lll_lock_wait () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:140 > #1 0x0000003a83209ad6 in _L_lock_752 () from /lib64/libpthread.so.0 > #2 0x0000003a832099d7 in __pthread_mutex_lock (mutex=0x1182f60) at pthread_mutex_lock.c:65 > #3 0x00000000004e7ec9 in qemu_mutex_lock (mutex=) at qemu-thread-posix.c:54 > #4 0x0000000000507df5 in channel_event (event=3, info=0x2a3c610) at ui/spice-core.c:234 > #5 0x00007f269f77be87 in reds_stream_free (s=0x2a3c590) at reds.c:4073 > #6 0x00007f269f75b64f in red_channel_client_disconnect (rcc=0x7f267c069ec0) at red_channel.c:961 > #7 0x00007f269f75a131 in red_peer_handle_incoming (handler=0x7f267c06a5a0, stream=0x2a3c590) > at red_channel.c:150 > #8 red_channel_client_receive (rcc=0x7f267c069ec0) at red_channel.c:158 > #9 0x00007f269f761fbc in handle_channel_events (in_listener=0x7f267c06a5f8, events=) > at red_worker.c:9566 > #10 0x00007f269f776672 in red_worker_main (arg=) at red_worker.c:10813 > #11 0x0000003a83207b31 in start_thread (arg=0x7f26822fc700) at pthread_create.c:305 > #12 0x0000003a82edfd2d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:115 > > Thread 1 (Thread 0x7f269f72e9c0 (LWP 17232)): > #0 0x0000003a8320e01d in read () at ../sysdeps/unix/syscall-template.S:82 > #1 0x00007f269f75daaa in receive_data (n=4, in_buf=0x7fffe7a5a02c, fd=18) at red_worker.h:150 > #2 read_message (message=0x7fffe7a5a02c, fd=18) at red_worker.h:163 > #3 red_dispatcher_disconnect_cursor_peer (rcc=0x7f267c0c0f60) at red_dispatcher.c:157 > #4 0x00007f269f75c20d in red_client_destroy (client=0x2a35400) at red_channel.c:1189 > #5 0x00007f269f778335 in reds_client_disconnect (client=0x2a35400) at reds.c:624 > ---Type to continue, or q to quit--- > #6 0x00007f269f75a131 in red_peer_handle_incoming (handler=0x2a35b50, stream=0x2b037d0) at red_channel.c:150 > #7 red_channel_client_receive (rcc=0x2a35470) at red_channel.c:158 > #8 0x00007f269f75b1e8 in red_channel_client_event (fd=, event=, > data=) at red_channel.c:774 > #9 0x000000000045e561 in fd_trampoline (chan=, cond=, opaque=) > at iohandler.c:97 > #10 0x0000003a84e427ed in g_main_dispatch (context=0x27fc510) at gmain.c:2441 > #11 g_main_context_dispatch (context=0x27fc510) at gmain.c:3014 > #12 0x00000000004c3da3 in glib_select_poll (err=false, xfds=0x7fffe7a5a2e0, wfds=0x7fffe7a5a260, rfds= > 0x7fffe7a5a1e0) at /home/berrange/src/virt/qemu/vl.c:1495 > #13 main_loop_wait (nonblocking=) at /home/berrange/src/virt/qemu/vl.c:1541 > #14 0x000000000040fdd1 in main_loop () at /home/berrange/src/virt/qemu/vl.c:1570 > #15 main (argc=, argv=, envp=) > at /home/berrange/src/virt/qemu/vl.c:3563 > (gdb) > >