offtopic: Running JLinkGDBServer + arm-none-eabi-gdb

Step 1) Run JLinkGDBServer and set device
(in JLinkGDBServer /bin folder, issue:) ./JLinkGDBServer -device STM32F103CB

Step 2) In a separated terminal, run arm-none-eabi-gdb and load .elf file
(in toolchain's /bin folder, issue:) ./arm-none-eabi-gdb file myprogram.elf

Step 3) In the newly opened arm-none-eabi-gdb prompt, issue the following cmds:

target remote: 2331
load
monitor reset
continue

Those steps are more than enough to verify if debugger is working properly. Eventual adaptations (JTAG, SWD) must be done if needed.

Reference: https://community.freescale.com/thread/317201