[Qemu-devel] [PATCH v2] vhost-user: fix watcher need be removed when vhost-user hotplug

[Yunjian Wang]

From: w00273186 <address@hidden>

"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 (address@hidden) 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 (address@hidden) 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 <address@hidden>
---
 net/vhost-user.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/vhost-user.c b/net/vhost-user.c
index 00a0c1c..8da314d 100644
--- a/net/vhost-user.c
+++ b/net/vhost-user.c
@@ -153,6 +153,10 @@ static void vhost_user_cleanup(NetClientState *nc)
     if (nc->queue_index == 0) {
         Chardev *chr = qemu_chr_fe_get_driver(&s->chr);
 
+        if (s->watch) {
+            g_source_remove(s->watch);
+            s->watch = 0;
+        }
         qemu_chr_fe_deinit(&s->chr);
         object_unparent(OBJECT(chr));
     }
-- 
1.8.3.1