[k64f] quit debugger mode cause BUS FAULT error

[qiaojingx]

Description

When using command "quit" to exit debugger mode, BUS FAULT error will occur on FRDM-K64F.

Test Code

tests/test-buffer.js; deps/jerryscript/jerry-client-ws.py

Steps to Reproduction

1. make BOARD=frdm_k64f DEBUGGER=on JS=tests/test-buffer.js
2. cp outdir/frdm_k64f/zephyr/zephyr.bin /media/<username>/MBED/
3. add route and addr on PC: ip route add 192.168.1/24 dev eno1 ip addr add 192.168.1.2 dev eno1
4. python deps/jerryscript/jerry-debugger/jerry-client-ws.py --display 10 192.168.1.1
5. Try command break, continue, list, help, quit, etc.

Actual Result

command quit cause BUS FAULT error on FRDM-K64F.

Expected Result

No error.

Test Builds

Branch	Commit Id	Target Device	Test Date	Result
master	2b033e1	FRDM-K64F	Jun 12, 2018	Fail

Additional Information