sudo apt install qemu qemu-system

# update .bashrc
source .bashrc

# tunctl install
sudo apt install uml-utilities
# tunctl usage:
# Create: tunctl [-b] [-u owner] [-g group] [-t device-name] [-f tun-clone-device]
# Delete: tunctl -d device-name [-f tun-clone-device]

# brctl intsll
sudo apt install bridge-utils
# To manually create a bridge interface br0:
Usage: brctl [commands]
commands:
        addbr           <bridge>                add bridge
        delbr           <bridge>                delete bridge
        addif           <bridge> <device>       add interface to bridge
        delif           <bridge> <device>       delete interface from bridge
        hairpin         <bridge> <port> {on|off}        turn hairpin on/off
        setageing       <bridge> <time>         set ageing time
        setbridgeprio   <bridge> <prio>         set bridge priority
        setfd           <bridge> <time>         set bridge forward delay
        sethello        <bridge> <time>         set hello time
        setmaxage       <bridge> <time>         set max message age
        setpathcost     <bridge> <port> <cost>  set path cost
        setportprio     <bridge> <port> <prio>  set port priority
        show            [ <bridge> ]            show a list of bridges
        showmacs        <bridge>                show a list of mac addrs
        showstp         <bridge>                show bridge stp info
        stp             <bridge> {on|off}       turn stp on/off


# To add interface tap0 and tap1 to the bridge br0
brctl addif br0 tap0
brctl addif br0 tap1

# Note that you need to set the link status to up on the added interfaces.
ip link set dev tap0 up
ip link set dev tap1 up

# qemu-ifup and qemu-ifdown
# create files /etc/qemu-ifup and /etc/qemu-ifdown, for example:
# /etc/qemu-ifup:

#! /bin/sh
switch=br0
ifconfig $1 up
 #ip link set $1 up
brctl addif ${switch} $1

# /etc/qemu-ifdown:

#! /bin/sh
switch=br0
brctl delif ${switch} $1
ifconfig $1 down
#ip link set $1 down
#tunctl -d $1

#! /bin/bash
tunctl -t tap0 -u username
brctl addbr br0

ip link set dev tap0 up
ip link set dev br0 up

ip addr add 192.168.0.11/24 dev tap0
ip addr add 192.168.0.1/24 dev br0

#brctl addif br0 tap0

#! /bin/sh
# Script to bring a network (tap) device for qemu up.
# The idea is to add the tap device to the same bridge
# as we have default routing to.

# in order to be able to find brctl
PATH=$PATH:/sbin:/usr/sbin
ip=$(which ip)

if [ -n "$ip" ]; then
   ip link set "$1" up
else
   brctl=$(which brctl)
   if [ ! "$ip" -o ! "$brctl" ]; then
     echo "W: $0: not doing any bridge processing: neither ip nor brctl utility not found" >&2
     exit 0
   fi
   ifconfig "$1" 0.0.0.0 up
fi

switch=$(ip route ls | \
    awk '/^default / {
          for(i=0;i<NF;i++) { if ($i == "dev") { print $(i+1); next; } }
         }'
        )

# only add the interface to default-route bridge if we
# have such interface (with default route) and if that
# interface is actually a bridge.
# It is possible to have several default routes too
for br in $switch; do
    if [ -d /sys/class/net/$br/bridge/. ]; then
        if [ -n "$ip" ]; then
          ip link set "$1" master "$br"
        else
          brctl addif $br "$1"
        fi
        exit    # exit with status of the previous command
    fi
done

echo "W: $0: no bridge for guest interface found" >&2

### compile.sh

#make x86_64_defconfig
make defconfig
make menuconfig
make

### run.sh
#!/bin/bash

qemu-system-x86_64 -smp 4 -m 4096 -kernel linux/arch/x86_64/boot/bzImage -append "root=/dev/sda rw" -drive format=raw,file=ubuntu.ext4 -net nic -net user

# qemu-system-x86_64 -smp 1 -m 512 -kernel linux/arch/x86_64/boot/bzImage -append "root=/dev/sda rw" -drive format=raw,file=ubuntu.ext4 -net nic -net user --enable-kvm

# qemu-system-x86_64 -smp 4 -m 4096 -kernel linux/arch/x86_64/boot/bzImage -append "root=/dev/sda rw" -drive format=raw,file=ubuntu.ext4 -net nic -net tap,ifname=tap0

# qemu-system-x86_64 -smp 4 -m 4096 -kernel linux/arch/x86_64/boot/bzImage -append "root=/dev/sda rw" -drive format=raw,file=ubuntu.ext4 -net nic -net tap,ifname=tap0 --enable-kvm

### compile.sh

#make ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabihf- vexpress_defconfig
make ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabihf- defconfig
make ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabihf- menuconfig
make ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabihf-

### run.sh
#!/bin/bash

qemu-system-arm -M vexpress-a9 -m 512M -kernel linux/arch/arm/boot/zImage -dtb linux/arch/arm/boot/dts/vexpress-v2p-ca9.dtb -append "root=/dev/mmcblk0 rw console=ttyAMA0" -sd ubuntu-arm.ext4 -net nic -net user

# qemu-system-arm -M vexpress-a9 -m 512M -kernel linux/arch/arm/boot/zImage -dtb linux/arch/arm/boot/dts/vexpress-v2p-ca9.dtb -nographic -append "root=/dev/mmcblk0 rw console=ttyAMA0" -sd ubuntu-arm.ext4 -net nic -net user

# qemu-system-arm -M vexpress-a9 -m 512M -kernel linux/arch/arm/boot/zImage -dtb linux/arch/arm/boot/dts/vexpress-v2p-ca9.dtb -nographic -append "root=/dev/mmcblk0 rw console=ttyAMA0" -sd ubuntu-arm.ext4 --enable-kvm

# qemu-system-arm -M vexpress-a9 -m 512M -kernel linux/arch/arm/boot/zImage -dtb linux/arch/arm/boot/dts/vexpress-v2p-ca9.dtb -nographic -append "root=/dev/mmcblk0 rw console=ttyAMA0" -sd ubuntu-arm.ext4 -net nic -net tap,ifname=tap0

### compile.sh

make ARCH=arm64 CROSS_COMPILE=aarch64-none-linux-gnu- defconfig
make ARCH=arm64 CROSS_COMPILE=aarch64-none-linux-gnu- menuconfig
make ARCH=arm64 CROSS_COMPILE=aarch64-none-linux-gnu-

### run.sh
#!/bin/bash

qemu-system-aarch64 -machine virt -cpu cortex-a53 -m 1024M -kernel linux/arch/arm64/boot/Image -append "root=/dev/vda rw" -hda ubuntu-arm64.ext4 -net nic -net user

# qemu-system-aarch64 -machine virt -cpu cortex-a53 -m 1024M -kernel linux/arch/arm64/boot/Image -append "root=/dev/vda rw console=ttyAMA0" -hda ubuntu-arm64.ext4 -net nic -net user

# qemu-system-aarch64 -machine virt -cpu cortex-a53 -m 1024M -kernel linux/arch/arm64/boot/Image -nographic -append "root=/dev/vda rw console=ttyAMA0" -hda ubuntu-arm64.ext4 -net nic -net user

# qemu-system-aarch64 -machine virt -cpu cortex-a53 -m 1024M -kernel linux/arch/arm64/boot/Image -append "root=/dev/vda rw console=ttyAMA0" -hda ubuntu-arm64.ext4 -net nic -net tap,ifname=tap0