Now that you have gdbserver installed on the target and a cross GDB on the host you can start a debug session.
The connection between GDB and gdbserver can be through a network or a serial interface. In the case of a network connection, you launch gdbserver with the TCP port number to listen on and, optionally, an IP address to accept connections from. In most cases you don't care which IP address is going to connect, so you can just give the port number. In this example gdbserver waits for a connection on port
10000 from any host:
# gdbserver :10000 ./hello-world Process hello-world created; pid = 103 Listening on port 10000
Next, start the copy of GDB from your toolchain, giving the same program as ...