diff --git a/mysql-test/r/innodb_mysql.result b/mysql-test/r/innodb_mysql.result
index abfb4211bfe..5b3ca972467 100644
--- a/mysql-test/r/innodb_mysql.result
+++ b/mysql-test/r/innodb_mysql.result
@@ -984,4 +984,27 @@ a	b	c
 15	1	1
 16	1	1
 DROP TABLE t1,t2;
+CREATE TABLE t1 (a INT, PRIMARY KEY (a)) ENGINE=InnoDB;
+INSERT INTO t1 VALUES (1),(2),(3),(4),(5),(6),(7),(8);
+INSERT INTO t1 SELECT a + 8  FROM t1;
+INSERT INTO t1 SELECT a + 16 FROM t1;
+CREATE PROCEDURE p1 ()
+BEGIN
+DECLARE i INT DEFAULT 50;
+DECLARE cnt INT;
+START TRANSACTION;
+ALTER TABLE t1 ENGINE=InnoDB;
+COMMIT;
+START TRANSACTION;
+WHILE (i > 0) DO
+SET i = i - 1;
+SELECT COUNT(*) INTO cnt FROM t1 LOCK IN SHARE MODE;
+END WHILE;
+COMMIT;
+END;|
+CALL p1();
+CALL p1();
+CALL p1();
+DROP PROCEDURE p1;
+DROP TABLE t1;
 End of 5.0 tests
diff --git a/mysql-test/t/innodb_mysql.test b/mysql-test/t/innodb_mysql.test
index 3a9d31ba804..63431e10bbf 100644
--- a/mysql-test/t/innodb_mysql.test
+++ b/mysql-test/t/innodb_mysql.test
@@ -740,6 +740,8 @@ SELECT COUNT(*) FROM t1 FORCE INDEX(idx_b, idx_c)
 set @@sort_buffer_size=default;
 
 DROP TABLE t1,t2;
+
+
 # Bug#27296 Assertion in ALTER TABLE SET DEFAULT in Linux Debug build
 # (possible deadlock).
 #
@@ -787,4 +789,56 @@ SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY c,a;
 
 DROP TABLE t1,t2;
 
+
+#
+# Bug #29644: alter table hangs if records locked in share mode by long
+# running transaction
+#
+
+CREATE TABLE t1 (a INT, PRIMARY KEY (a)) ENGINE=InnoDB;
+
+INSERT INTO t1 VALUES (1),(2),(3),(4),(5),(6),(7),(8);
+INSERT INTO t1 SELECT a + 8  FROM t1;
+INSERT INTO t1 SELECT a + 16 FROM t1;
+
+DELIMITER |;
+CREATE PROCEDURE p1 ()
+BEGIN
+  DECLARE i INT DEFAULT 50;
+  DECLARE cnt INT;
+  START TRANSACTION;
+    ALTER TABLE t1 ENGINE=InnoDB;
+  COMMIT;
+  START TRANSACTION;
+  WHILE (i > 0) DO
+    SET i = i - 1;
+    SELECT COUNT(*) INTO cnt FROM t1 LOCK IN SHARE MODE;
+  END WHILE;
+  COMMIT;
+END;|
+
+DELIMITER ;|
+
+CONNECT (con1,localhost,root,,);
+CONNECT (con2,localhost,root,,);
+
+CONNECTION con1;
+SEND CALL p1();
+CONNECTION con2;
+SEND CALL p1();
+CONNECTION default;
+CALL p1();
+
+CONNECTION con1;
+REAP;
+CONNECTION con2;
+REAP;
+CONNECTION default;
+DISCONNECT con1;
+DISCONNECT con2;
+
+DROP PROCEDURE p1;
+DROP TABLE t1;
+
+
 --echo End of 5.0 tests
diff --git a/sql/ha_innodb.cc b/sql/ha_innodb.cc
index b03dc9bb986..1c952f490da 100644
--- a/sql/ha_innodb.cc
+++ b/sql/ha_innodb.cc
@@ -6721,17 +6721,6 @@ ha_innobase::store_lock(
 		    && !thd->tablespace_op
 		    && thd->lex->sql_command != SQLCOM_TRUNCATE
 		    && thd->lex->sql_command != SQLCOM_OPTIMIZE
-
-#ifdef __WIN__
-                /* For alter table on win32 for succesful operation
-                completion it is used TL_WRITE(=10) lock instead of
-                TL_WRITE_ALLOW_READ(=6), however here in innodb handler
-                TL_WRITE is lifted to TL_WRITE_ALLOW_WRITE, which causes
-                race condition when several clients do alter table
-                simultaneously (bug #17264). This fix avoids the problem. */
-		    && thd->lex->sql_command != SQLCOM_ALTER_TABLE
-#endif
-
 		    && thd->lex->sql_command != SQLCOM_CREATE_TABLE) {
 
 			lock_type = TL_WRITE_ALLOW_WRITE;
diff --git a/sql/sql_base.cc b/sql/sql_base.cc
index bf1c6d7cb0d..d117f2b499a 100644
--- a/sql/sql_base.cc
+++ b/sql/sql_base.cc
@@ -2938,13 +2938,6 @@ TABLE *open_ltable(THD *thd, TABLE_LIST *table_list, thr_lock_type lock_type)
 
   if (table)
   {
-#if defined( __WIN__) || defined(OS2)
-    /* Win32 can't drop a file that is open */
-    if (lock_type == TL_WRITE_ALLOW_READ)
-    {
-      lock_type= TL_WRITE;
-    }
-#endif /* __WIN__ || OS2 */
     table_list->lock_type= lock_type;
     table_list->table=	   table;
     table->grant= table_list->grant;