Build/Run Linux under QEMU. Only podman and qemu-user-binfmt need to be installed.
Build is based on containers to ensure it can be reproduced on any machine. Rootfs is derived from a container image.
A custom Linux kernel can be built instead by creating a symlink named linux.
# build system using:
./build.sh
# run system using:
./run.sh /path/to/qemu-system-aarch64
# exit QEMU with ctrl-a + x
# debug kernel and firmwares using:
./debug.sh /path/to/qemu-system-aarch64
# additional gdb commands were added, like arm-exception-level. See gdb.py.
# to debug qemu itself:
./run.sh gdb --args /path/to/qemu-system-aarch64
# to create an archive containing the whole stack:
./build.sh
./archive_artifacts.sh stack.tar.xz
It's possible to automate execution of commands in the VM:
# Current working directory is mounted as /host in VM
# A script named guest.sh can be used to launch a nested guest
# Finally, a custom command can be passed to init script using INIT env var
# To boot a nested guest, and call hostname:
INIT='env INIT=hostname /host/guest.sh qemu-system-aarch64' ./run.sh qemu-system-aarch64
# In case command fail, init will trigger a Kernel panic
INIT='false' ./run.sh qemu-system-aarch64
Linux is compiled with -O2 (and relies on it), making it hard to debug.
However, you can enable debugging for specific functions by using:
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index 27725f1ab5ab..e76fd4da8179 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -4,6 +4,8 @@
#include <linux/compiler_types.h>
+#define DEBUGGER __attribute__((optimize("O0")))
+
#ifndef __ASSEMBLY__
#ifdef __KERNEL__
And marking functions to debug with DEBUGGER attribute.