# Linux Kernel Module Cheat
The perfect emulation setup to study and develop the <<linux-kernel>> v5.9.2, kernel modules, <<qemu-buildroot-setup,QEMU>>, <<gem5-buildroot-setup,gem5>> and x86_64, ARMv7 and ARMv8 <<userland-assembly,userland>> and <<baremetal-setup,baremetal>> assembly, <<c,ANSI C>>, <<cpp,C++>> and <<posix,POSIX>>. <<gdb>> and <<kgdb>> just work. Powered by <<about-the-qemu-buildroot-setup,Buildroot>> and <<about-the-baremetal-setup,crosstool-NG>>. Highly automated. Thoroughly documented. Automated <<test-this-repo,tests>>.

##### 24.22.9.1. M5_OVERRIDE_PY_SOURCE

https://stackoverflow.com/questions/52312070/how-to-modify-a-file-under-src-python-and-run-it-without-rebuilding-in-gem5

Running gem5 with the `M5_OVERRIDE_PY_SOURCE=true` environment variable allows you to modify a file under src/python and run it without rebuilding in gem5?

We set this environment variable by default in our run script.

How `M5_OVERRID_PY_SOURCE` works is shown at: gem5 `m5.objects` module.