Re: [libvirt] [PATCH] fix bug libvirt daemon deadlock when another force console break down an existed console client when this deadlock hanppened, libvirtd backtrace as follow, a typical ABBA deadlock circumstance:

(gdb) thread 23 [Switching to thread 23 (Thread 0x7fbb54810700 (LWP 296966))] (gdb) bt at rpc/virnetserverclient.c:1503 client=client@entry=0x5641d20e20a0, msg=0x7fbb08003ab0, rerr=rerr@entry=0x7fbb5480f7b0, procedure=201, type=type@entry=3, serial=9) at rpc/virnetserverprogram.c:173 msg=<optimized out>, rerr=rerr@entry=0x7fbb5480f7b0, procedure=<optimized out>, serial=<optimized out>) at rpc/virnetserverprogram.c:222 opaque=opaque@entry=0x5641d20e20a0) at stream.c:246 force=force@entry=true) at conf/virchrdev.c:386 at qemu/qemu_driver.c:16188 st=st@entry=0x7fbb08008fc0, flags=1) at libvirt-domain.c:9363 rerr=0x7fbb5480fc10, msg=<optimized out>, client=0x5641d20e4e80) at remote_dispatch.h:8540 rerr=0x7fbb5480fc10, args=0x7fbb08005eb0, ret=<optimized out>) at remote_dispatch.h:8505 server=0x5641d20be420, prog=0x5641d20da580) at rpc/virnetserverprogram.c:437 msg=0x5641d20e9a20) at rpc/virnetserverprogram.c:307 srv=0x5641d20be420) at rpc/virnetserver.c:148 ---Type <return> to continue, or q <return> to quit--- (gdb) thread 26 [Switching to thread 26 (Thread 0x7fbb87a378c0 (LWP 295636))] (gdb) bt at stream.c:286 at rpc/virnetserverclient.c:1247 at rpc/virnetserverclient.c:1457 at util/vireventpoll.c:508 Signed-off-by: LanceLiu <liu.lance.89(a)gmail.com&gt; --- src/remote/remote_daemon_stream.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/remote/remote_daemon_stream.c b/src/remote/remote_daemon_stream.c index 1f6e783..b27348f 100644 --- a/src/remote/remote_daemon_stream.c +++ b/src/remote/remote_daemon_stream.c @@ -284,14 +284,16 @@ daemonStreamEvent(virStreamPtr st, int events, void *opaque) * -1 on fatal client error */ static int -daemonStreamFilter(virNetServerClientPtr client ATTRIBUTE_UNUSED, +daemonStreamFilter(virNetServerClientPtr client,

virNetMessagePtr msg, void *opaque) { daemonClientStream *stream = opaque; int ret = 0; + virObjectUnlock(client); virMutexLock(&stream->priv->lock); + virObjectLock(client); if (msg->header.type != VIR_NET_STREAM && msg->header.type != VIR_NET_STREAM_HOLE)