From 337c1b3ee83033a185daa4e2df8c8a36f54c2bf7 Mon Sep 17 00:00:00 2001
From: Sergei Golubchik <sergii@pisem.net>
Date: Fri, 19 Apr 2013 20:35:37 +0200
Subject: [PATCH] fix plugin locking/unlocking when assisted discovery fails

---
 sql/sql_table.cc | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/sql/sql_table.cc b/sql/sql_table.cc
index 8ad9f10bc24..60fd630001a 100644
--- a/sql/sql_table.cc
+++ b/sql/sql_table.cc
@@ -4420,6 +4420,16 @@ bool mysql_create_table_no_lock(THD *thd,
       goto err;
 
     ha_err= hton->discover_table_structure(hton, thd, &share, create_info);
+
+    /*
+      if discovery failed, the plugin will be auto-unlocked, as it
+      was locked on the THD, see above.
+      if discovery succeeded, the plugin was replaced by a globally
+      locked plugin, that will be unlocked by free_table_share()
+    */
+    if (ha_err)
+      share.db_plugin= 0; // will be auto-freed, locked above on the THD
+
     free_table_share(&share);
 
     if (ha_err)