debian/patches/extra/0018-chardev-char-socket-set-s-listener-NULL-in-char_sock.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Yajun Wu <yajunw@nvidia.com>
   3 Date: Tue, 14 Feb 2023 10:14:30 +0800
   4 Subject: [PATCH] chardev/char-socket: set s->listener = NULL in
   5  char_socket_finalize
   6 MIME-Version: 1.0
   7 Content-Type: text/plain; charset=UTF-8
   8 Content-Transfer-Encoding: 8bit
   9
  10 After live migration with virtio block device, qemu crash at:
  11
  12         #0  0x000055914f46f795 in object_dynamic_cast_assert (obj=0x559151b7b090, typename=0x55914f80fbc4 "qio-channel", file=0x55914f80fb90 "/images/testvfe/sw/qemu.gerrit/include/io/channel.h", line=30, func=0x55914f80fcb8 <__func__.17257> "QIO_CHANNEL") at ../qom/object.c:872
  13         #1  0x000055914f480d68 in QIO_CHANNEL (obj=0x559151b7b090) at /images/testvfe/sw/qemu.gerrit/include/io/channel.h:29
  14         #2  0x000055914f4812f8 in qio_net_listener_set_client_func_full (listener=0x559151b7a720, func=0x55914f580b97 <tcp_chr_accept>, data=0x5591519f4ea0, notify=0x0, context=0x0) at ../io/net-listener.c:166
  15         #3  0x000055914f580059 in tcp_chr_update_read_handler (chr=0x5591519f4ea0) at ../chardev/char-socket.c:637
  16         #4  0x000055914f583dca in qemu_chr_be_update_read_handlers (s=0x5591519f4ea0, context=0x0) at ../chardev/char.c:226
  17         #5  0x000055914f57b7c9 in qemu_chr_fe_set_handlers_full (b=0x559152bf23a0, fd_can_read=0x0, fd_read=0x0, fd_event=0x0, be_change=0x0, opaque=0x0, context=0x0, set_open=false, sync_state=true) at ../chardev/char-fe.c:279
  18         #6  0x000055914f57b86d in qemu_chr_fe_set_handlers (b=0x559152bf23a0, fd_can_read=0x0, fd_read=0x0, fd_event=0x0, be_change=0x0, opaque=0x0, context=0x0, set_open=false) at ../chardev/char-fe.c:304
  19         #7  0x000055914f378caf in vhost_user_async_close (d=0x559152bf21a0, chardev=0x559152bf23a0, vhost=0x559152bf2420, cb=0x55914f2fb8c1 <vhost_user_blk_disconnect>) at ../hw/virtio/vhost-user.c:2725
  20         #8  0x000055914f2fba40 in vhost_user_blk_event (opaque=0x559152bf21a0, event=CHR_EVENT_CLOSED) at ../hw/block/vhost-user-blk.c:395
  21         #9  0x000055914f58388c in chr_be_event (s=0x5591519f4ea0, event=CHR_EVENT_CLOSED) at ../chardev/char.c:61
  22         #10 0x000055914f583905 in qemu_chr_be_event (s=0x5591519f4ea0, event=CHR_EVENT_CLOSED) at ../chardev/char.c:81
  23         #11 0x000055914f581275 in char_socket_finalize (obj=0x5591519f4ea0) at ../chardev/char-socket.c:1083
  24         #12 0x000055914f46f073 in object_deinit (obj=0x5591519f4ea0, type=0x5591519055c0) at ../qom/object.c:680
  25         #13 0x000055914f46f0e5 in object_finalize (data=0x5591519f4ea0) at ../qom/object.c:694
  26         #14 0x000055914f46ff06 in object_unref (objptr=0x5591519f4ea0) at ../qom/object.c:1202
  27         #15 0x000055914f4715a4 in object_finalize_child_property (obj=0x559151b76c50, name=0x559151b7b250 "char3", opaque=0x5591519f4ea0) at ../qom/object.c:1747
  28         #16 0x000055914f46ee86 in object_property_del_all (obj=0x559151b76c50) at ../qom/object.c:632
  29         #17 0x000055914f46f0d2 in object_finalize (data=0x559151b76c50) at ../qom/object.c:693
  30         #18 0x000055914f46ff06 in object_unref (objptr=0x559151b76c50) at ../qom/object.c:1202
  31         #19 0x000055914f4715a4 in object_finalize_child_property (obj=0x559151b6b560, name=0x559151b76630 "chardevs", opaque=0x559151b76c50) at ../qom/object.c:1747
  32         #20 0x000055914f46ef67 in object_property_del_child (obj=0x559151b6b560, child=0x559151b76c50) at ../qom/object.c:654
  33         #21 0x000055914f46f042 in object_unparent (obj=0x559151b76c50) at ../qom/object.c:673
  34         #22 0x000055914f58632a in qemu_chr_cleanup () at ../chardev/char.c:1189
  35         #23 0x000055914f16c66c in qemu_cleanup () at ../softmmu/runstate.c:830
  36         #24 0x000055914eee7b9e in qemu_default_main () at ../softmmu/main.c:38
  37         #25 0x000055914eee7bcc in main (argc=86, argv=0x7ffc97cb8d88) at ../softmmu/main.c:48
  38
  39 In char_socket_finalize after s->listener freed, event callback function
  40 vhost_user_blk_event will be called to handle CHR_EVENT_CLOSED.
  41 vhost_user_blk_event is calling qio_net_listener_set_client_func_full which
  42 is still using s->listener.
  43
  44 Setting s->listener = NULL after object_unref(OBJECT(s->listener)) can
  45 solve this issue.
  46
  47 Signed-off-by: Yajun Wu <yajunw@nvidia.com>
  48 Acked-by: Jiri Pirko <jiri@nvidia.com>
  49 Message-Id: <20230214021430.3638579-1-yajunw@nvidia.com>
  50 Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
  51 Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
  52 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
  53 (cherry-picked from commit b8a7f51f59e28d5a8e0c07ed3919cc9695560ed2)
  54 Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
  55 ---
  56  chardev/char-socket.c | 1 +
  57  1 file changed, 1 insertion(+)
  58
  59 diff --git a/chardev/char-socket.c b/chardev/char-socket.c
  60 index 879564aa8a..b00efb1482 100644
  61 --- a/chardev/char-socket.c
  62 +++ b/chardev/char-socket.c
  63 @@ -1065,6 +1065,7 @@ static void char_socket_finalize(Object *obj)
  64          qio_net_listener_set_client_func_full(s->listener, NULL, NULL,
  65                                                NULL, chr->gcontext);
  66          object_unref(OBJECT(s->listener));
  67 +        s->listener = NULL;
  68      }
  69      if (s->tls_creds) {
  70          object_unref(OBJECT(s->tls_creds));