ctylihuai left a comment (kamailio/kamailio#4238)
What do you mean with "the tcp_main process was not configured as a worker"? As said, I would recommend to do an update before investigating further.
tcp_main did not initialize tcp_reader_ltimer and io_w, The tcp_reader_ltimer should not have a value. (gdb) p tcp_reader_ltimer $1 = {prev_ticks = 0, timer_lst = {h0 = {{next = 0x0, prev = 0x0} <repeats 12336 times>, {next = 0x0, prev = 0xaaaac2a10158 <tcp_main_ltimer+134680>}, {next = 0x0, prev = 0x0} <repeats 4047 times>}, h1 = {{ next = 0x0, prev = 0x0} <repeats 512 times>}, h2 = {{next = 0x0, prev = 0x0} <repeats 512 times>}, expired = {next = 0x0, prev = 0x0}}}
Unfortunately, we are in a commercial environment now and cannot make major version upgrade .