msgr: clear_pipe inside pipe_lock on mark_down_all

Observed a segfault in rebind -> mark_down_all -> clear_pipe -> put that
may have been due to a racing thread clearing the connection_state pointer.
Do the clear_pipe() call under the protection of pipe_lock, as we do in
all other contexts.

Signed-off-by: Sage Weil <sage@inktank.com>
(cherry picked from commit 5fc1dabfb3b2cbffdee3214d24d7769d6e440e45)

Conflicts:

	src/msg/SimpleMessenger.cc

1 files changed, 2 insertions, 0 deletions

diff --git a/src/msg/SimpleMessenger.cc b/src/msg/SimpleMessenger.cc
index 148300f159c..dd6b1bd944b 100644
--- a/src/msg/SimpleMessenger.cc
+++ b/src/msg/SimpleMessenger.cc
@@ -562,6 +562,8 @@ void SimpleMessenger::mark_down_all()
     p->unregister_pipe();
     p->pipe_lock.Lock();
     p->stop();
+    if (p->connection_state)
+      p->connection_state->clear_pipe(p);
     p->pipe_lock.Unlock();
   }
   lock.Unlock();