Recommended Setup¶
The simplest way to achieve a functional setup is to follow the steps listed in this repo.
Virtual Machine Setup¶
Practice work is designed to run on a QEMU based virtual machine. Kernel code is developed and built on the host machine and then deployed and run on the virtual machine.
In order to run and use the virtual machine the following packages are required on a Debian/Ubuntu system:
flex
bison
build-essential
gcc-multilib
libncurses5-dev
qemu-system-x86
qemu-system-arm
python3
minicom
The kvm
package is not strictly required, but will make the virtual machine
faster by using KVM support (with the -enable-kvm
option to QEMU). If kvm
is absent, the virtual machine will still run (albeit slower) using emulation.
The virtual machine setup uses prebuild Yocto images that it downloads and a kernel image that it builds itself. The following images are supported:
core-image-minimal-qemu
core-image-minimal-dev-qemu
core-image-sato-dev-qemu
core-image-sato-qemu
core-image-sato-sdk-qemu
By default, core-image-minimal-qemu
it used. This setting can be changed by
updating the YOCTO_IMAGE
variable in tools/labs/qemu/Makefile
.
Starting the Virtual Machine¶
You start the virtual machine in the tools/labs/
folder by running make
boot
:
.../linux/tools/labs$ make boot
The first run of the make boot
command will compile the kernel image and it
will take longer. Subsequent runs will only start the QEMU virtual machine,
with verbose output provided:
.../linux/tools/labs$ make boot
mkdir /tmp/tmp.7rWv63E9Wf
sudo mount -t ext4 -o loop core-image-minimal-qemux86.ext4 /tmp/tmp.7rWv63E9Wf
sudo make -C /home/razvan/school/so2/linux.git modules_install INSTALL_MOD_PATH=/tmp/tmp.7rWv63E9Wf
make: Entering directory '/home/razvan/school/so2/linux.git'
INSTALL crypto/crypto_engine.ko
INSTALL drivers/crypto/virtio/virtio_crypto.ko
INSTALL drivers/net/netconsole.ko
DEPMOD 4.19.0+
make: Leaving directory '/home/razvan/school/so2/linux.git'
sudo umount /tmp/tmp.7rWv63E9Wf
rmdir /tmp/tmp.7rWv63E9Wf
sleep 1 && touch .modinst
qemu/create_net.sh tap0
dnsmasq: failed to create listening socket for 172.213.0.1: Address already in use
qemu/create_net.sh tap1
dnsmasq: failed to create listening socket for 127.0.0.1: Address already in use
/home/razvan/school/so2/linux.git/tools/labs/templates/assignments/6-e100/nttcp -v -i &
nttcp-l: nttcp, version 1.47
nttcp-l: running in inetd mode on port 5037 - ignoring options beside -v and -p
bind: Address already in use
nttcp-l: service-socket: bind:: Address already in use, errno=98
ARCH=x86 qemu/qemu.sh -kernel /home/razvan/school/so2/linux.git/arch/x86/boot/bzImage -device virtio-serial -chardev pty,id=virtiocon0 -device virtconsole,chardev=virtiocon0 -serial pipe:pipe1 -serial pipe:pipe2 -netdev tap,id=tap0,ifname=tap0,script=no,downscript=no -net nic,netdev=tap0,model=virtio -netdev tap,id=tap1,ifname=tap1,script=no,downscript=no -net nic,netdev=tap1,model=i82559er -drive file=core-image-minimal-qemux86.ext4,if=virtio,format=raw -drive file=disk1.img,if=virtio,format=raw -drive file=disk2.img,if=virtio,format=raw --append "root=/dev/vda loglevel=15 console=hvc0" --display none -s
qemu-system-i386: -chardev pty,id=virtiocon0: char device redirected to /dev/pts/68 (label virtiocon0)
Note
To show the QEMU console use
.../linux/tools/labs$ QEMU_DISPLAY=gtk make boot
This will show the VGA output and will also give
access to the standard keyboard.
Note
The virtual machine setup scripts and configuration files are located
in tools/labs/qemu/
.
Connecting to the Virtual Machine¶
Once the virtual machine is started you can connect to it on the serial port. A
symbolic link named serial.pts
is created to the emulated serial port
device:
.../linux/tools/labs$ ls -l serial.pts
lrwxrwxrwx 1 razvan razvan 11 Apr 1 08:03 serial.pts -> /dev/pts/68
On the host you use the minicom
command to connect to the virtual machine
via the serial.pts
link:
.../linux/tools/labs$ minicom -D serial.pts
[...]
Poky (Yocto Project Reference Distro) 2.3 qemux86 /dev/hvc0
qemux86 login: root
root@qemux86:~#
Note
When you connect to the virtual machine, simply enter root
at the
login prompt and you will get a root console, no password required.
Note
You exit minicom
by pressing Ctrl+a
and then x
. You will
get a confirmation prompt and then you will exit minicom
.