libceph: initialize ack_stamp to avoid unnecessary connection reset

Commit 4cf9d544631c recorded when an outgoing ceph message was ACKed,
in order to avoid unnecessary connection resets when an OSD is busy.

However, ack_stamp is uninitialized, so there is a window between
when the message is sent and when it is ACKed in which handle_timeout()
interprets the unitialized value as an expired timeout, and resets
the connection unnecessarily.

Close the window by initializing ack_stamp.

Signed-off-by: Jim Schutt <jaschut@sandia.gov>
Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 1 insertions, 0 deletions

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index c340e2e0765b..9918e9eb276e 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -2307,6 +2307,7 @@ struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags)
         m->front_max = front_len;
         m->front_is_vmalloc = false;
         m->more_to_follow = false;
+        m->ack_stamp = 0;
         m->pool = NULL;
 
         /* middle */