How to solve the warning: ”Address 0xXXX is outside of physical memory, stopping fetch" during full system simulation with RISCV 03 CPU

[ptzheng]

I try to run RISCV full system simulation using the configs as the script 'riscv-ubuntu-run.py' in configs/example/gem5_library and change CPU type to O3 CPU. During simulation, the warnings appear frequently:

It seems that the warnings will slow down the simulation because it frequently stops instruction fetching:

What's the meaning of these warnings? How could I solve the warnings?