From beac9714ef693f97feb68e1793fa1ad30d8a96e4 Mon Sep 17 00:00:00 2001
From: johannst <johannes.stoelp@gmail.com>
Date: Wed, 12 May 2021 00:02:36 +0200
Subject: added old blog entries

---
 .../20191027-kernel-debugging-qemu/build_initrd.sh | 50 ++++++++++++++++++++++
 .../20191027-kernel-debugging-qemu/build_kernel.sh | 38 ++++++++++++++++
 2 files changed, 88 insertions(+)
 create mode 100644 content/20191027-kernel-debugging-qemu/build_initrd.sh
 create mode 100644 content/20191027-kernel-debugging-qemu/build_kernel.sh

(limited to 'content/20191027-kernel-debugging-qemu')

diff --git a/content/20191027-kernel-debugging-qemu/build_initrd.sh b/content/20191027-kernel-debugging-qemu/build_initrd.sh
new file mode 100644
index 0000000..74f9896
--- /dev/null
+++ b/content/20191027-kernel-debugging-qemu/build_initrd.sh
@@ -0,0 +1,50 @@
+#!/bin/bash
+
+set -e
+
+BUSYBOX=busybox-1.31.0
+INITRD=$PWD/initramfs.cpio.gz
+
+## Build busybox
+
+echo "[+] configure & build $BUSYBOX ..."
+[[ ! -d $BUSYBOX ]] && {
+    wget https://busybox.net/downloads/$BUSYBOX.tar.bz2
+    bunzip2 $BUSYBOX.tar.bz2 && tar xf $BUSYBOX.tar
+}
+
+cd $BUSYBOX
+make defconfig
+sed -i 's/# CONFIG_STATIC .*/CONFIG_STATIC=y/' .config
+make -j4 busybox
+make install
+
+## Create initrd
+
+echo "[+] create initrd $INITRD ..."
+
+cd _install
+
+# 1. create initrd folder structure
+mkdir -p bin sbin etc proc sys usr/bin usr/sbin dev
+
+# 2. create init process
+cat <<EOF > init
+#!/bin/sh
+
+mount -t proc none /proc
+mount -t sysfs none /sys
+
+exec setsid cttyhack sh
+EOF
+chmod +x init
+
+# 3. create device nodes
+sudo mknod dev/tty c 5 0
+sudo mknod dev/tty0 c 4 0
+sudo mknod dev/ttyS0 c 4 64
+
+# 4. created compressed initrd
+find . -print0                      \
+    | cpio --null -ov --format=newc \
+    | gzip -9 > $INITRD
diff --git a/content/20191027-kernel-debugging-qemu/build_kernel.sh b/content/20191027-kernel-debugging-qemu/build_kernel.sh
new file mode 100644
index 0000000..f1e15bb
--- /dev/null
+++ b/content/20191027-kernel-debugging-qemu/build_kernel.sh
@@ -0,0 +1,38 @@
+#!/bin/bash
+
+set -e
+
+LINUX=linux-5.3.7
+wget https://cdn.kernel.org/pub/linux/kernel/v5.x/$LINUX.tar.xz
+unxz $LINUX.tar.xz && tar xf $LINUX.tar
+
+cd $LINUX
+
+cat <<EOF > kernel_fragment.config
+# 64bit kernel
+CONFIG_64BIT=y
+# enable support for compressed initrd (gzip)
+CONFIG_BLK_DEV_INITRD=y
+CONFIG_RD_GZIP=y
+# support for ELF and #! binary format
+CONFIG_BINFMT_ELF=y
+CONFIG_BINFMT_SCRIPT=y
+# /dev
+CONFIG_DEVTMPFS=y
+CONFIG_DEVTMPFS_MOUNT=y
+# tty & console
+CONFIG_TTY=y
+CONFIG_SERIAL_8250=y
+CONFIG_SERIAL_8250_CONSOLE=y
+# pseudo fs
+CONFIG_PROC_FS=y
+CONFIG_SYSFS=y
+# debugging
+CONFIG_DEBUG_INFO=y
+CONFIG_PRINTK=y
+CONFIG_EARLY_PRINTK=y
+EOF
+
+make tinyconfig
+./scripts/kconfig/merge_config.sh -n ./kernel_fragment.config
+make -j4
-- 
cgit v1.2.3