libceph: fix mutex coverage for ceph_con_close
Hold the mutex while twiddling all of the state bits to avoid possible
races. While we're here, make not of why we cannot close the socket
directly.
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 6e2f678..e65b15d 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -503,6 +503,7 @@
*/
void ceph_con_close(struct ceph_connection *con)
{
+ mutex_lock(&con->mutex);
dout("con_close %p peer %s\n", con,
ceph_pr_addr(&con->peer_addr.in_addr));
clear_bit(NEGOTIATING, &con->state);
@@ -515,11 +516,16 @@
clear_bit(KEEPALIVE_PENDING, &con->flags);
clear_bit(WRITE_PENDING, &con->flags);
- mutex_lock(&con->mutex);
reset_connection(con);
con->peer_global_seq = 0;
cancel_delayed_work(&con->work);
mutex_unlock(&con->mutex);
+
+ /*
+ * We cannot close the socket directly from here because the
+ * work threads use it without holding the mutex. Instead, let
+ * con_work() do it.
+ */
queue_con(con);
}
EXPORT_SYMBOL(ceph_con_close);