mnesia: Synchronize lock cleanup after mnesia down

Bad timing could lead to hanging transactions after a mnesia down from a
node with sticky locks.

Excellent bug report from janchochol

Situation:
* node A and B have copies of table T
* node A ows sticky of table T
* node A goes down (e.g. crash)
* node B tries to perform transactional operation on table T
  (e.g. mnesia:select)

In this situation there is possibility that first (and maybe other)
transaction on node B will hang indefinitely.
This is caused by race condition, when transaction process send lock
request operation to node A and waits for reply. When node A is down
it will never send reply, so process on node B will be stuck
forever.
Reason is that message sent to mnesia_locker gen_server from
mnesia_locker:mnesia_down can be received after mnesia_locker gen_server
already replies to transaction processes with {switch, N, Req} and
node N is down.
Monitoring remote process when sending request to other node should
be safe solution.

1 files changed, 4 insertions, 10 deletions

diff --git a/lib/mnesia/src/mnesia.appup.src b/lib/mnesia/src/mnesia.appup.src
index 355aafb215..c245299740 100644
--- a/lib/mnesia/src/mnesia.appup.src
+++ b/lib/mnesia/src/mnesia.appup.src
@@ -1,22 +1,16 @@
 %% -*- erlang -*-
 {"%VSN%",
  [
-  {"4.7.1",  [{restart_application, mnesia}]},
-  {"4.7",  [{restart_application, mnesia}]},
-  {"4.6",  [{restart_application, mnesia}]},
-  {"4.5.1",  [{restart_application, mnesia}]},
-  {"4.5",    [{restart_application, mnesia}]},
+  {<<"4\\.1[0-9].*">>, [{restart_application, mnesia}]},
+  {<<"4\\.[5-9].*">>, [{restart_application, mnesia}]},
   {"4.4.19", [{restart_application, mnesia}]},
   {"4.4.18", [{restart_application, mnesia}]},
   {"4.4.17", [{restart_application, mnesia}]},
   {"4.4.16", [{restart_application, mnesia}]}
  ],
  [
-  {"4.7.1",  [{restart_application, mnesia}]},
-  {"4.7",  [{restart_application, mnesia}]},
-  {"4.6",  [{restart_application, mnesia}]},
-  {"4.5.1",  [{restart_application, mnesia}]},
-  {"4.5",    [{restart_application, mnesia}]},
+  {<<"4\\.1[0-9].*">>, [{restart_application, mnesia}]},
+  {<<"4\\.[5-9].*">>, [{restart_application, mnesia}]},
   {"4.4.19", [{restart_application, mnesia}]},
   {"4.4.18", [{restart_application, mnesia}]},
   {"4.4.17", [{restart_application, mnesia}]},