qemu and linux as submodlues, S98 vs S99, readme benefits of Ctrl + C

.gitignore

@@ -4,6 +4,8 @@
 *.o
 *.out
 *.tmp
+*~
 .tmp_versions
+/rootfs_overlay/etc/init.d/S99
 Module.symvers
 modules.order

.gitmodules

@@ -1,3 +1,9 @@
 [submodule "buildroot"]
 	path = buildroot
 	url = https://github.com/buildroot/buildroot
+[submodule "qemu"]
+	path = qemu
+	url = https://github.com/cirosantilli/qemu
+[submodule "linux"]
+	path = linux
+	url = https://github.com/cirosantilli/linux

README.md

@@ -122,6 +122,8 @@ TODO: Ctrl + C kills the emulator, it is not sent to guest processes. See:
 - <https://github.com/cloudius-systems/osv/issues/49>
 - <https://unix.stackexchange.com/questions/167165/how-to-pass-ctrl-c-in-qemu>
 
+This is however fortunate when running QEMU with GDB, as the Ctrl + C reaches GDB and breaks.
+
 ## Automatic startup commands
 
 When debugging a module, it becomes tedious to wait for build and re-type:
@@ -131,10 +133,14 @@ When debugging a module, it becomes tedious to wait for build and re-type:
 
 Instead, you can add your test commands to:
 
-    rootfs_overlay/etc/init.d/S99
+    cd rootfs_overlay/etc/init.d
+    cp S98 S99
+    vim S99
 
 and they will be run automatically before the login prompt.
 
+`S99` is already gitignored for you.
+
 ## Debugging
 
 To GDB the Linux kernel, first run:

buildroot_config_fragment

@@ -2,6 +2,7 @@ BR2_GLOBAL_PATCH_DIR="../global_patch_dir"
 BR2_LINUX_KERNEL_CONFIG_FRAGMENT_FILES="../kernel_config_fragment"
 BR2_PACKAGE_BUSYBOX_CONFIG_FRAGMENT_FILES="../busybox_config_fragment"
 BR2_PACKAGE_KERNEL_MODULE=y
+BR2_PACKAGE_OVERRIDE_FILE=../buildroot_override
 BR2_PACKAGE_STRACE=y
 BR2_ROOTFS_OVERLAY="../rootfs_overlay"
 

buildroot_override

@@ -0,0 +1,2 @@
+HOST_QEMU_OVERRIDE_SRCDIR = ../qemu
+LINUX_OVERRIDE_SRCDIR = ../linux

rootfs_overlay/etc/init.d/S98

@@ -0,0 +1,6 @@
+#!/bin/sh
+# For temparary test commands, first copy this file to to
+# S99 which is already gitignored.
+echo 'S98'
+# insmod /hello.ko
+exit 0

rootfs_overlay/etc/init.d/S99

@@ -1,4 +0,0 @@
-#!/bin/sh
-echo 'S99'
-# insmod /hello.ko
-exit 0

run

@@ -43,7 +43,6 @@ env \
   HOST_QEMU_OPTS="--enable-debug --enable-sdl --extra-cflags='-DDEBUG_PL061=1' --with-sdlabi=2.0" \
   host-qemu-rebuild \
   linux-rebuild \
-  kernel_module-rebuild \
   all \
 ;
 cd ..