Nginx process endlessly stuck in err_unwind function causes 100% CPU

openresty version ： openresty-1.13.6.1
error.log：nginx: lua atpanic: Lua VM crashed, reason: not enough memory
STACK1：
Traceback (most recent call last):

File "luajit21.py", line 588, in invoke

bt = lj_debug_dumpstack(L, 0, 30, base, full)

File "luajit21.py", line 423, in lj_debug_dumpstack

frame, size = lj_debug_frame(L, base, level, bot)

File "luajit21.py", line 218, in lj_debug_frame

if frame_gc(frame) == obj2gco(L):

File "luajit21.py", line 177, in frame_gc

return gcref(frame['fr']['func'])

File "luajit21.py", line 170, in gcref

return r['gcptr32'].cast(typ("uintptr_t")).cast(typ("GCobj*"))

g
gdb.MemoryError: Cannot access memory at address 0xfffffffffffffff8
E
Error occurred in Python command: Cannot access memory at address 0xfffffffffffffff8

STACK2：
#0 err_unwind (L=L@entry=0x41e9f378, stopcf=0x7ffcddad1520, errcode=errcode@entry=0) at lj_err.c:109

#1 0x00007f988b3504a5 in lj_err_unwind_dwarf (version=, actions=1, uexclass=5500374307216568836, uex=0x7f988c51e760, ctx=0x7ffcddad1170) at lj_err.c:240

#2 0x00007f988a347c33 in _Unwind_RaiseException () from /lib64/libgcc_s.so.1

#3 0x00007f988b350329 in err_raise_ext (errcode=4) at lj_err.c:301

#4 lj_err_throw (L=L@entry=0x41e9f378, errcode=errcode@entry=4) at lj_err.c:515

#5 0x00007f988b350563 in lj_err_mem (L=L@entry=0x41e9f378) at lj_err.c:551

#6 0x00007f988b350000 in lj_mem_newgco (L=L@entry=0x41e9f378, size=20) at lj_gc.c:833

#7 0x00007f988b3530ec in func_newL (L=L@entry=0x41e9f378, pt=pt@entry=0x41ee8010, env=0x41ea09d8) at lj_func.c:122

#8 0x00007f988b353310 in lj_func_newL_gc (L=0x41e9f378, pt=, parent=0x415cde28) at lj_func.c:160

#9 0x00007f988b34bbe9 in lj_BC_FNEW () from /usr/local/NSP/luajit/lib/libluajit-5.1.so.2

#10 0x00007f988b35d0bd in lua_pcall (L=L@entry=0x41e9f378, nargs=nargs@entry=0, nresults=nresults@entry=1, errfunc=errfunc@entry=0) at lj_api.c:1129

#11 0x00000000004f9c75 in ngx_http_lua_cache_load_code (log=log@entry=0x2062db70, L=L@entry=0x41e9f378, key=key@entry=0x21327480 "nhlf_cdbb7e422b70672672ea5d04e77ae42c")

at ../ngx_lua-0.10.11/src/ngx_http_lua_cache.c:56

#12 0x00000000004f9f1c in ngx_http_lua_cache_loadfile (log=0x2062db70, L=L@entry=0x41e9f378, script=0x31727c38 "/usr/local/NSP/etc/router/router_ext.luac",

cache_key=0x21327480 "nhlf_cdbb7e422b70672672ea5d04e77ae42c") at ../ngx_lua-0.10.11/src/ngx_http_lua_cache.c:232

#13 0x00000000004fb9c7 in ngx_http_lua_access_handler_file (r=0x31726cf0) at ../ngx_lua-0.10.11/src/ngx_http_lua_accessby.c:219

#14 0x00000000004fb5d0 in ngx_http_lua_access_handler (r=0x31726cf0) at ../ngx_lua-0.10.11/src/ngx_http_lua_accessby.c:163

#15 0x0000000000459dbb in ngx_http_core_access_phase (r=, ph=0x17ab770) at src/http/ngx_http_core_module.c:1087

#16 0x000000000045562d in ngx_http_core_run_phases (r=r@entry=0x31726cf0) at src/http/ngx_http_core_module.c:862

#17 0x0000000000455722 in ngx_http_handler (r=r@entry=0x31726cf0) at src/http/ngx_http_core_module.c:845

#18 0x000000000046024e in ngx_http_process_request (r=0x31726cf0) at src/http/ngx_http_request.c:1986

#19 0x0000000000460ac7 in ngx_http_process_request_line (rev=0x7f981e7851c8) at src/http/ngx_http_request.c:1076

#20 0x000000000044a09c in ngx_epoll_process_events (cycle=, timer=, flags=) at src/event/modules/ngx_epoll_module.c:968

#21 0x00000000004413df in ngx_process_events_and_timers (cycle=cycle@entry=0x15ac050) at src/event/ngx_event.c:266

#22 0x0000000000447f21 in ngx_worker_process_cycle (cycle=cycle@entry=0x15ac050, data=data@entry=0x17) at src/os/unix/ngx_process_cycle.c:821

#23 0x00000000004468c6 in ngx_spawn_process (cycle=cycle@entry=0x15ac050, proc=proc@entry=0x447ea0 <ngx_worker_process_cycle>, data=data@entry=0x17,

name=name@entry=0x5a58e5 "worker process", respawn=respawn@entry=-4) at src/os/unix/ngx_process.c:198

#24 0x0000000000448240 in ngx_start_worker_processes (cycle=cycle@entry=0x15ac050, n=32, type=type@entry=-4) at src/os/unix/ngx_process_cycle.c:396

#25 0x0000000000448ef5 in ngx_master_process_cycle (cycle=0x15ac050, cycle@entry=0x15a6230) at src/os/unix/ngx_process_cycle.c:250

#26 0x0000000000421583 in main (argc=, argv=) at src/core/nginx.c:387

Start with err_unwind in lj_err.c and trace the reported lj_err_unwind_dwarf, err_raise_ext, lj_err_mem, and lj_mem_newgco frames through ngx_http_lua_cache_load_code in ngx_http_lua_cache.c. Use the supplied stack and Lua VM out-of-memory message to investigate why unwinding loops and leaves a worker at 100% CPU; done means the reported endless loop is explained and no longer occurs.