[Qemu-devel] [PATCH] vhost-user: fix watcher need be removed when vhost-user hotplug

[Yunjian Wang <wangyunjian@huawei.com>]

From: w00273186 <wangyunjian@huawei.com>

"nc" is freed after hotplug vhost-user, but the watcher don't be removed.
The QEMU crash when the watcher access the "nc" on socket disconnect.

Call Trace:
    #0  object_get_class (obj=obj@entry=0x2) at qom/object.c:751
    #1  0x00007fc031c79f41 in qemu_chr_fe_disconnect (be=<optimized out>) at chardev/char.c:1048
    #2  0x00007fc031bd62e0 in net_vhost_user_watch (chan=<optimized out>, cond=<optimized out>, opaque=<optimized out>) at net/vhost-user.c:191
    #3  0x00007fc02c23e99a in g_main_context_dispatch () from /lib64/libglib-2.0.so.0
    #4  0x00007fc031ccfc0c in glib_pollfds_poll () at util/main-loop.c:213
    #5  os_host_main_loop_wait (timeout=<optimized out>) at util/main-loop.c:261
    #6  main_loop_wait (nonblocking=nonblocking@entry=0) at util/main-loop.c:517
    #7  0x00007fc03193bc87 in main_loop () at vl.c:1899
    #8  main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4719

Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
---
 net/vhost-user.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/vhost-user.c b/net/vhost-user.c
index 00a0c1c..5cc2178 100644
--- a/net/vhost-user.c
+++ b/net/vhost-user.c
@@ -155,6 +155,10 @@ static void vhost_user_cleanup(NetClientState *nc)
 
         qemu_chr_fe_deinit(&s->chr);
         object_unparent(OBJECT(chr));
+        if (s->watch) {
+            g_source_remove(s->watch);
+            s->watch = 0;
+        }
     }
 
     qemu_purge_queued_packets(nc);
-- 
1.8.3.1