Setup Qemu for arm64 android kernel running
Fetch the android kernel
Google provide the manifest to fetch the kernel soruce, corresponding config files and corss compile toolchain
mkdir android-kernel && cd android-kernel
repo init -u https://android.googlesource.com/kernel/manifest -b common-android11-5.4
repo sync -c -d -j8
Enable the 9P FS for host and guest folder sharing by adding following configs to the kernel config gki_defconfig is the kernel config file we will used to compile the kernel.
vi common/arch/arm64/configs/gki_defconfig
CONFIG_9P_FS_SECURITY=y
CONFIG_NET_9P=y
CONFIG_NET_9P_VIRTIO=y
CONFIG_NET_9P_DEBUG=y
CONFIG_9P_FS=y
CONFIG_9P_FS_POSIX_ACL=y
CONFIG_PCI=y
CONFIG_VIRTIO_PCI=y
Compile the kernel
We will combine the rootfs together with kernel imaqge - vmlinux The configuration CONFIG_INITRAMFS_SOURCE is used to indicate the rootfs place.
cd android-kernel/common-modules/virtual-device
goldfish_defconfig.fragment:CONFIG_INITRAMFS_SOURCE="/media/data-nvm/temp/rootfs/rfs"
BUILD_CONFIG=common-modules/virtual-device/build.config.goldfish.aarch64 build/build.sh
Prepare a busybox - the rootfs creation
We will build and generate rootfs from busybox. To build the busybox we need first download a toolchian. Here is a link for a Linaro toolchain : gcc-linaro-5.5.0-2017.10-x86_64_aarch64-linux-gnu.tar.xz It can be downloaded from https://releases.linaro.org/components/toolchain/binaries/latest-5/aarch64-linux-gnu/
For example, we put the toolchain under folder /media/data-nvm/temp/rootfs/gcc-linaro-5.5.0-2017.10-x86_64_aarch64-linux-gnu, then run below commands:
export PATH=/media/data-nvm/temp/rootfs/gcc-linaro-5.5.0-2017.10-x86_64_aarch64-linux-gnu/bin:$PATH
export ARCH=arm64
export CROSS_COMPILE=aarch64-linux-gnu-
Config the busybix to make it build to static bianry.
make menuconfig
setting
[*] Build static binary (no shared libs)
Compile busybox:
make
make install
## below command is important to copy the libc dependencies:
cp -ar gcc-linaro-5.5.0-2017.10-x86_64_aarch64-linux-gnu/aarch64-linux-gnu/libc/* _install/lib
Create rootfs
cd _install
mkdir dev etc lib sys proc tmp var home root mnt
vi etc/profile
#!/bin/sh
export HOSTNAME=weller
export USER=root
export HOME=/home
export PS1="[$USER@$HOSTNAME \W]\# "
PATH=/bin:/sbin:/usr/bin:/usr/sbin
LD_LIBRARY_PATH=/lib:/usr/lib:$LD_LIBRARY_PATH
export PATH LD_LIBRARY_PATH
vi etc/inittab
::sysinit:/etc/init.d/rcS
::respawn:-/bin/sh
::askfirst:-/bin/sh
::ctrlaltdel:/bin/umount -a -r
vi etc/fstab
#device mount-point type options dump fsck order
proc /proc proc defaults 0 0
tmpfs /tmp tmpfs defaults 0 0
sysfs /sys sysfs defaults 0 0
tmpfs /dev tmpfs defaults 0 0
debugfs /sys/kernel/debug debugfs defaults 0 0
kmod_mount /mnt 9p trans=virtio 0 0
vi etc/fstab
#device mount-point type options dump fsck order
proc /proc proc defaults 0 0
tmpfs /tmp tmpfs defaults 0 0
sysfs /sys sysfs defaults 0 0
tmpfs /dev tmpfs defaults 0 0
debugfs /sys/kernel/debug debugfs defaults 0 0
kmod_mount /mnt 9p trans=virtio 0 0
cd dev/
sudo mknod console c 5 1
Launch with QEMU
sudo apt install qemu-system-arm
qemu-system-aarch64 -machine virt -cpu cortex-a57 -machine type=virt -m 1024 -smp 4 -kernel /media/data-sdb2/tmp/android-kernel/out/android11-5.4/dist/Image --append "rdinit=/linuxrc root=/dev/vda rw console=ttyAMA0 loglevel=8" -nographic -fsdev local,security_model=passthrough,id=fsdev0,path=//media/data-nvm/temp/rootfs/share -device virtio-9p-pci,id=fs0,fsdev=fsdev0,mount_tag=kmod_mount -drive format=raw,file=/media/data-nvm/temp/rootfs/hd1 -net nic,model=virtio,macaddr=DE:AD:BE:EF:28:05
boot with disk
qemu-system-aarch64 -machine virt -cpu cortex-a57 -machine type=virt -m 1024 -smp 4 -kernel /media/data-sdb2/tmp/android-kernel/out/android11-5.4/dist/Image -nographic -drive if=none,file=/media/data-nvm/temp/rootfs/rootfs_ext4.img,id=drive-virtio-disk0 -device virtio-blk-device,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 --append "noinitrd root=/dev/vda rw console=ttyAMA0 loglevel=8" -fsdev local,security_model=passthrough,id=fsdev0,path=//media/data-nvm/temp/rootfs/share -device virtio-9p-pci,id=fs0,fsdev=fsdev0,mount_tag=kmod_mount -drive format=raw,file=/media/data-nvm/temp/rootfs/hd1 -net nic,model=virtio,macaddr=DE:AD:BE:EF:28:05
