diff --git a/lualib/skynet.lua b/lualib/skynet.lua
index 78f5bef9..13843199 100644
--- a/lualib/skynet.lua
+++ b/lualib/skynet.lua
@@ -143,13 +143,15 @@ end
 function suspend(co, result, command, param, size)
 	if not result then
 		local session = session_coroutine_id[co]
-		local addr = session_coroutine_address[co]
-		if session ~= 0 then
-			-- only call response error
-			c.send(addr, skynet.PTYPE_ERROR, session, "")
+		if session then -- coroutine may fork by others (session is nil)
+			local addr = session_coroutine_address[co]
+			if session ~= 0 then
+				-- only call response error
+				c.send(addr, skynet.PTYPE_ERROR, session, "")
+			end
+			session_coroutine_id[co] = nil
+			session_coroutine_address[co] = nil
 		end
-		session_coroutine_id[co] = nil
-		session_coroutine_address[co] = nil
 		error(debug.traceback(co,tostring(command)))
 	end
 	if command == "CALL" then
@@ -696,6 +698,10 @@ function skynet.task(ret)
 	return t
 end
 
+function skynet.term(service)
+	return _error_dispatch(0, service)
+end
+
 -- Inject internal debug framework
 local debug = require "skynet.debug"
 debug(skynet, dispatch_message)
diff --git a/lualib/skynet/debug.lua b/lualib/skynet/debug.lua
index 5b7b5afa..4105ddcb 100644
--- a/lualib/skynet/debug.lua
+++ b/lualib/skynet/debug.lua
@@ -54,6 +54,10 @@ function dbgcmd.RUN(source, filename)
 	skynet.ret(skynet.pack(table.concat(output, "\n")))
 end
 
+function dbgcmd.TERM(service)
+	skynet.term(service)
+end
+
 local function _debug_dispatch(session, address, cmd, ...)
 	local f = dbgcmd[cmd]
 	assert(f, cmd)