Build/Run Linux under QEMU.
Only podman and qemu-user-static (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.
Build is cached thanks to podman and ccache, ensuring quick rebuilds.
All revisions are automatically built, tagged, and added to build release.
Builds are generated with debug information (including macros) and frame
pointers enabled. As well, compile_commands.json is generated by default for
all the projects built using intercept-build from LLVM.
This ensures a good developer experience out of the box.
NOTE: there is no clean command nor any dependency analysis.
Every project is cloned in its own versioned folder, and a symlink is
dynamically set by each build script to point to the right version everytime.
Thus, update or switch branches should not require any git clean -ffdx.
# build system using:
./build.sh
# run system using:
./run.sh /path/to/qemu-system-aarch64
# exit QEMU with ctrl-a + x
# debug kernel, firmwares and bootloader 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.