diff --git a/mysql-test/include/stop_dump_threads.inc b/mysql-test/include/stop_dump_threads.inc
new file mode 100644
index 00000000000..ae33c963d9a
--- /dev/null
+++ b/mysql-test/include/stop_dump_threads.inc
@@ -0,0 +1,32 @@
+# ==== Purpose ====
+#
+# Stop all dump threads on the server of the current connection.
+#
+# ==== Usage ====
+#
+# --source include/stop_dump_threads.inc
+
+--let $include_filename= stop_dump_threads.inc
+--source include/begin_include_file.inc
+
+
+--let $_sdt_show_rpl_debug_info_old= $show_rpl_debug_info
+--let $show_rpl_debug_info= 1
+--disable_query_log
+--disable_result_log
+
+--let $_sdt_dump_thread_id= `SELECT ID FROM INFORMATION_SCHEMA.PROCESSLIST WHERE COMMAND = 'Binlog dump'`
+
+while ($_sdt_dump_thread_id != '')
+{
+  eval KILL $_sdt_dump_thread_id;
+  --let $wait_condition= SELECT COUNT(*) = 0 FROM INFORMATION_SCHEMA.PROCESSLIST WHERE ID = $_sdt_dump_thread_id
+  --source include/wait_condition.inc
+
+  --let $_sdt_dump_thread_id= `SELECT ID FROM INFORMATION_SCHEMA.PROCESSLIST WHERE COMMAND = 'Binlog dump'`
+}
+
+--let $show_rpl_debug_info= $_sdt_show_rpl_debug_info_old
+
+--let $include_filename= stop_dump_threads.inc
+--source include/end_include_file.inc
diff --git a/mysql-test/include/uninstall_semisync.inc b/mysql-test/include/uninstall_semisync.inc
index 11668d1db97..0a4c55fa4f2 100644
--- a/mysql-test/include/uninstall_semisync.inc
+++ b/mysql-test/include/uninstall_semisync.inc
@@ -13,6 +13,11 @@
 UNINSTALL PLUGIN rpl_semi_sync_slave;
 
 --connection master
+# After BUG#17638477 fix, uninstallation of rpl_semi_sync_master
+#  is not allowed when there are semi sync slaves. Hence kill
+#  all dump threads before uninstalling it.
+SET GLOBAL rpl_semi_sync_master_enabled = OFF;
+--source include/stop_dump_threads.inc
 UNINSTALL PLUGIN rpl_semi_sync_master;
 --enable_warnings
 
diff --git a/mysql-test/suite/rpl/r/rpl_semi_sync.result b/mysql-test/suite/rpl/r/rpl_semi_sync.result
index 0377716698c..8c6cb58324a 100644
--- a/mysql-test/suite/rpl/r/rpl_semi_sync.result
+++ b/mysql-test/suite/rpl/r/rpl_semi_sync.result
@@ -439,9 +439,8 @@ Rpl_semi_sync_slave_status	OFF
 #
 # Clean up
 #
+include/uninstall_semisync.inc
 include/stop_slave.inc
-UNINSTALL PLUGIN rpl_semi_sync_slave;
-UNINSTALL PLUGIN rpl_semi_sync_master;
 change master to master_user='root',master_password='';
 include/start_slave.inc
 drop table t1;
diff --git a/mysql-test/suite/rpl/r/rpl_semi_sync_uninstall_plugin.result b/mysql-test/suite/rpl/r/rpl_semi_sync_uninstall_plugin.result
new file mode 100644
index 00000000000..d5cf690c978
--- /dev/null
+++ b/mysql-test/suite/rpl/r/rpl_semi_sync_uninstall_plugin.result
@@ -0,0 +1,36 @@
+include/master-slave.inc
+[connection master]
+INSTALL PLUGIN rpl_semi_sync_master SONAME 'semisync_master.so';
+INSTALL PLUGIN rpl_semi_sync_slave SONAME 'semisync_slave.so';
+UNINSTALL PLUGIN rpl_semi_sync_slave;
+UNINSTALL PLUGIN rpl_semi_sync_master;
+CREATE TABLE t1(i int);
+INSERT INTO t1 values (1);
+DROP TABLE t1;
+include/install_semisync.inc
+call mtr.add_suppression("Plugin 'rpl_semi_sync_slave' cannot be uninstalled now");
+UNINSTALL PLUGIN rpl_semi_sync_slave;
+ERROR HY000: Unknown error
+call mtr.add_suppression("Plugin 'rpl_semi_sync_master' cannot be uninstalled now");
+UNINSTALL PLUGIN rpl_semi_sync_master;
+ERROR HY000: Unknown error
+CREATE TABLE t1(i int);
+INSERT INTO t1 values (2);
+DROP TABLE t1;
+include/assert.inc [semi sync slave status should be ON.]
+include/assert.inc [semi sync master status should be ON.]
+include/assert.inc [semi sync master clients should be 1.]
+SET GLOBAL rpl_semi_sync_master_enabled = OFF;
+include/assert.inc [semi sync master clients should be 1.]
+UNINSTALL PLUGIN rpl_semi_sync_master;
+ERROR HY000: Unknown error
+include/stop_slave.inc
+SET GLOBAL rpl_semi_sync_slave_enabled = OFF;
+include/start_slave.inc
+UNINSTALL PLUGIN rpl_semi_sync_slave;
+include/assert.inc [semi sync master clients should be 0.]
+UNINSTALL PLUGIN rpl_semi_sync_master;
+CREATE TABLE t1(i int);
+INSERT INTO t1 values (3);
+DROP TABLE t1;
+include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/t/rpl_semi_sync.test b/mysql-test/suite/rpl/t/rpl_semi_sync.test
index 21967fb6f8c..b78bb772fc9 100644
--- a/mysql-test/suite/rpl/t/rpl_semi_sync.test
+++ b/mysql-test/suite/rpl/t/rpl_semi_sync.test
@@ -598,19 +598,10 @@ SHOW STATUS LIKE 'Rpl_semi_sync_slave_status';
 --echo #
 --echo # Clean up
 --echo #
+--source include/uninstall_semisync.inc
 
 connection slave;
 source include/stop_slave.inc;
-UNINSTALL PLUGIN rpl_semi_sync_slave;
-
-connection master;
-# The dump thread may still be running on the master, and so the following
-# UNINSTALL could generate a warning about the plugin is busy.
-disable_warnings;
-UNINSTALL PLUGIN rpl_semi_sync_master;
-enable_warnings;
-
-connection slave;
 change master to master_user='root',master_password='';
 source include/start_slave.inc;
 
diff --git a/mysql-test/suite/rpl/t/rpl_semi_sync_uninstall_plugin-master.opt b/mysql-test/suite/rpl/t/rpl_semi_sync_uninstall_plugin-master.opt
new file mode 100644
index 00000000000..58029d28ace
--- /dev/null
+++ b/mysql-test/suite/rpl/t/rpl_semi_sync_uninstall_plugin-master.opt
@@ -0,0 +1 @@
+$SEMISYNC_PLUGIN_OPT
diff --git a/mysql-test/suite/rpl/t/rpl_semi_sync_uninstall_plugin-slave.opt b/mysql-test/suite/rpl/t/rpl_semi_sync_uninstall_plugin-slave.opt
new file mode 100644
index 00000000000..58029d28ace
--- /dev/null
+++ b/mysql-test/suite/rpl/t/rpl_semi_sync_uninstall_plugin-slave.opt
@@ -0,0 +1 @@
+$SEMISYNC_PLUGIN_OPT
diff --git a/mysql-test/suite/rpl/t/rpl_semi_sync_uninstall_plugin.test b/mysql-test/suite/rpl/t/rpl_semi_sync_uninstall_plugin.test
new file mode 100644
index 00000000000..094e044e0d2
--- /dev/null
+++ b/mysql-test/suite/rpl/t/rpl_semi_sync_uninstall_plugin.test
@@ -0,0 +1,143 @@
+###############################################################################
+# Bug#17638477 UNINSTALL AND INSTALL SEMI-SYNC PLUGIN CAUSES SLAVES TO BREAK
+#  Problem: Uninstallation of Semi sync plugin should be blocked when it is
+#  in use.
+#  Test case: Uninstallation of semi sync should be allowed
+#   On Master:
+#     1) When there is no dump thread
+#     2) When there are no semi sync slaves (i.e., async replication).
+#   On Slave:
+#     1) When there is no I/O thread
+#     2) When there are no semi sync enabled I/O thread (i.e.,async replication).
+###############################################################################
+
+--source include/have_semisync_plugin.inc
+--source include/not_embedded.inc
+--source include/have_binlog_format_statement.inc
+--source include/master-slave.inc
+
+###############################################################################
+# Case 1: Uninstallation of semi sync plugins should be allowed when it is
+#  not in use i.e., when asynchronous replication is active.
+###############################################################################
+# Step 1.1: Install semi sync master plugin on master
+eval INSTALL PLUGIN rpl_semi_sync_master SONAME '$SEMISYNC_MASTER_PLUGIN';
+
+# Step 1.2: Install semi sync slave plugin on slave
+--connection slave
+eval INSTALL PLUGIN rpl_semi_sync_slave SONAME '$SEMISYNC_SLAVE_PLUGIN';
+
+# Step 1.3: Uninstallation of semisync plugin on master and slave should be
+#  allowed at this state as there is no semi sync replication enabled between
+#  master and slave.
+UNINSTALL PLUGIN rpl_semi_sync_slave;
+--connection master
+UNINSTALL PLUGIN rpl_semi_sync_master;
+
+# Step 1.4: Check that replication is working fine at the end of the test case.
+CREATE TABLE t1(i int);
+INSERT INTO t1 values (1);
+DROP TABLE t1;
+--sync_slave_with_master
+
+###############################################################################
+# Case 2: Uninstallation of semi sync plugins should be disallowed
+#  when it is in use i.e., when semi sync replication is active
+###############################################################################
+# Step 2.1: Install and enable semi sync replication between master and slave
+--source include/install_semisync.inc
+
+# Step 2.2: Check that rpl_semi_sync_slave uninstallation on Slave is not
+#  possible at this state
+--connection slave
+call mtr.add_suppression("Plugin 'rpl_semi_sync_slave' cannot be uninstalled now");
+--error ER_UNKNOWN_ERROR
+UNINSTALL PLUGIN rpl_semi_sync_slave;
+
+# Step 2.3: Check that rpl_semi_sync_master uninstallation on Master is not
+#  possible at this state
+--connection master
+call mtr.add_suppression("Plugin 'rpl_semi_sync_master' cannot be uninstalled now");
+--error ER_UNKNOWN_ERROR
+UNINSTALL PLUGIN rpl_semi_sync_master;
+
+# Step 2.4: Check that replication is working fine at the end of the test case.
+CREATE TABLE t1(i int);
+INSERT INTO t1 values (2);
+DROP TABLE t1;
+--sync_slave_with_master
+
+# Step 2.5: Make sure rpl_semi_sync_master_status on Master and
+# rpl_semi_sync_slave_staus on Slave are ON
+--let $slave_status=[show status like "Rpl_semi_sync_slave_status", Value, 1]
+--let assert_cond= "$slave_status" = "ON"
+--let assert_text= semi sync slave status should be ON.
+--source include/assert.inc
+
+--connection master
+--let $master_status=[show status like "Rpl_semi_sync_master_status", Value, 1]
+--let assert_cond= "$master_status" = "ON"
+--let assert_text= semi sync master status should be ON.
+--source include/assert.inc
+
+--let $master_clients=[show status like "Rpl_semi_sync_master_clients", Value, 1]
+--let assert_cond= $master_clients = 1
+--let assert_text= semi sync master clients should be 1.
+--source include/assert.inc
+
+###############################################################################
+# Case 3: Uninstallation of semi sync plugin should be disallowed when there
+#  are semi sync slaves even though rpl_semi_sync_master_enabled= OFF;.
+###############################################################################
+# Step 3.1: Disable semi sync on master
+--connection master
+SET GLOBAL rpl_semi_sync_master_enabled = OFF;
+
+# Step 3.2: Check that still Rpl_semi_sync_master_clients is 1
+--let $master_clients=[show status like "Rpl_semi_sync_master_clients", Value, 1]
+--let assert_cond= $master_clients = 1
+--let assert_text= semi sync master clients should be 1.
+--source include/assert.inc
+
+# Step 3.3: Since Rpl_semi_sync_master_clients is 1, uninstallation of
+#  rpl_semi_sync_master should be disallowed.
+--error ER_UNKNOWN_ERROR
+UNINSTALL PLUGIN rpl_semi_sync_master;
+
+###############################################################################
+# Case 4: Uninstallation of semi sync plugin should be allowed when it is not
+#  in use. Same as Case 1 but this case is to check the case after enabling and
+#  disabling semi sync replication.
+###############################################################################
+
+# Step 4.1: Stop IO thread on slave.
+--connection slave
+--source include/stop_slave.inc
+
+# Step 4.2: Disable semi sync on slave.
+SET GLOBAL rpl_semi_sync_slave_enabled = OFF;
+
+# Step 4.3: Start IO thread on slave.
+--source include/start_slave.inc
+
+# Step 4.4: Uninstall semi sync plugin, it should be successful now.
+UNINSTALL PLUGIN rpl_semi_sync_slave;
+
+# Step 4.5: On Master, check that semi sync slaves are now '0'.
+--connection master
+--let $master_clients=[show status like "Rpl_semi_sync_master_clients", Value, 1]
+--let assert_cond= $master_clients = 0
+--let assert_text= semi sync master clients should be 0.
+--source include/assert.inc
+
+# Step 4.6: So uninstalling semi sync plugin should be allowed
+UNINSTALL PLUGIN rpl_semi_sync_master;
+
+# Step 4.7: Check that replication is working fine at the end of the test case
+CREATE TABLE t1(i int);
+INSERT INTO t1 values (3);
+DROP TABLE t1;
+--sync_slave_with_master
+
+# Cleanup
+source include/rpl_end.inc;
diff --git a/sql/sql_plugin.cc b/sql/sql_plugin.cc
index d54326af7aa..9851cb2739a 100644
--- a/sql/sql_plugin.cc
+++ b/sql/sql_plugin.cc
@@ -1930,6 +1930,49 @@ bool mysql_uninstall_plugin(THD *thd, const LEX_STRING *name)
     goto err;
   }
 
+#ifdef HAVE_REPLICATION
+  /* Block Uninstallation of semi_sync plugins (Master/Slave)
+     when they are busy
+   */
+  char buff[20];
+  /*
+    Master: If there are active semi sync slaves for this Master,
+    then that means it is busy and rpl_semi_sync_master plugin
+    cannot be uninstalled. To check whether the master
+    has any semi sync slaves or not, check Rpl_semi_sync_master_cliens
+    status variable value, if it is not 0, that means it is busy.
+  */
+  if (!strcmp(name->str, "rpl_semi_sync_master") &&
+      get_status_var(thd,
+                     plugin->plugin->status_vars,
+                     "Rpl_semi_sync_master_clients",buff) &&
+      strcmp(buff,"0") )
+  {
+    sql_print_error("Plugin 'rpl_semi_sync_master' cannot be uninstalled now. "
+                    "Stop any active semisynchronous slaves of this master "
+                    "first.\n");
+    my_error(ER_UNKNOWN_ERROR, MYF(0), name->str);
+    goto err;
+  }
+  /* Slave: If there is semi sync enabled IO thread active on this Slave,
+    then that means plugin is busy and rpl_semi_sync_slave plugin
+    cannot be uninstalled. To check whether semi sync
+    IO thread is active or not, check Rpl_semi_sync_slave_status status
+    variable value, if it is ON, that means it is busy.
+  */
+  if (!strcmp(name->str, "rpl_semi_sync_slave") &&
+      get_status_var(thd, plugin->plugin->status_vars,
+                     "Rpl_semi_sync_slave_status", buff) &&
+      !strcmp(buff,"ON") )
+  {
+    sql_print_error("Plugin 'rpl_semi_sync_slave' cannot be uninstalled now. "
+                    "Stop any active semisynchronous I/O threads on this slave "
+                    "first.\n");
+    my_error(ER_UNKNOWN_ERROR, MYF(0), name->str);
+    goto err;
+  }
+#endif
+
   plugin->state= PLUGIN_IS_DELETED;
   if (plugin->ref_count)
     push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN,
diff --git a/sql/sql_show.cc b/sql/sql_show.cc
index dcae4c63b02..ac63b2aaff9 100644
--- a/sql/sql_show.cc
+++ b/sql/sql_show.cc
@@ -2117,6 +2117,59 @@ void free_status_vars()
   delete_dynamic(&all_status_vars);
 }
 
+/**
+  @brief           Get the value of given status variable
+
+  @param[in]       thd        thread handler
+  @param[in]       list       list of SHOW_VAR objects in which function should
+                              search
+  @param[in]       name       name of the status variable
+  @param[in/out]   value      buffer in which value of the status variable
+                              needs to be filled in
+
+  @return          status
+    @retval        FALSE      if variable is not found in the list
+    @retval        TRUE       if variable is found in the list
+  NOTE: Currently this function is implemented just to support 'bool' status
+  variables and 'long' status variables *only*. It can be extended very easily
+  for further show_types in future if required.
+  TODO: Currently show_status_arary switch case is tightly coupled with
+  pos, end, buff, value variables and also it stores the values in a 'table'.
+  Decouple the switch case to fill the buffer value so that it can be used
+  in show_status_array() and get_status_var() to avoid duplicate code.
+ */
+
+bool get_status_var(THD* thd, SHOW_VAR *list, const char * name, char * const value)
+{
+  for (; list->name; list++)
+  {
+    int res= strcmp(list->name, name);
+    if (res == 0)
+    {
+      /*
+        if var->type is SHOW_FUNC, call the function.
+        Repeat as necessary, if new var is again SHOW_FUNC
+      */
+      SHOW_VAR tmp;
+      for (; list->type == SHOW_FUNC; list= &tmp)
+        ((mysql_show_var_func)(list->value))(thd, &tmp, value);
+      switch (list->type) {
+      case SHOW_BOOL:
+        strmov(value, *(bool*) list->value ? "ON" : "OFF");
+        break;
+      case SHOW_LONG:
+        int10_to_str(*(long*) list->value, value, 10);
+        break;
+      default:
+        /* not supported type */
+        DBUG_ASSERT(0);
+      }
+      return TRUE;
+    }
+  }
+  return FALSE;
+}
+
 /*
   Removes an array of SHOW_VAR entries from the output of SHOW STATUS
 
diff --git a/sql/sql_show.h b/sql/sql_show.h
index 406c75d8cbe..b6d520441c7 100644
--- a/sql/sql_show.h
+++ b/sql/sql_show.h
@@ -113,6 +113,7 @@ int add_status_vars(SHOW_VAR *list);
 void remove_status_vars(SHOW_VAR *list);
 void init_status_vars();
 void free_status_vars();
+bool get_status_var(THD* thd, SHOW_VAR *list, const char *name, char * const buff);
 void reset_status_vars();
 bool show_create_trigger(THD *thd, const sp_name *trg_name);
 void view_store_options(THD *thd, TABLE_LIST *table, String *buff);