nested-run.py

#!/usr/bin/env python3
import subprocess
import os
import random
import argparse

def main():
    parser = argparse.ArgumentParser(description='Launch nested vm for testing guest')
    parser.add_argument('--vhost-scsi', '-s',
                        action='store_true', default=False,
                        help='Add vhost-scsi device instead of vhost-nvme')
    parser.add_argument('--no-test-volume', '-n',
                        action='store_true', default=False,
                        help='Do not add any test volumes, just run alpine')

    parser.add_argument('--gdbserver', '-g',
                        action='store_true', default=False,
                        help='Run qemu with gdbserver attached. '
                        'Note that server runs against the qemu itself, '
                        'not the guest kernel')

    parser.add_argument('--dry-run', action='store_true', default=False,
                        help='Do not launch only print the command',)

    parser.add_argument('--cgroup', '-c', action='store', default=None,
                        help='Run in a memory cgroup')

    parser.add_argument('--tcp-serial', '-t', action='store_true',
                        help='''Attach to a tcp console (e.g netcat) on the host. And use it as
                        primary console. Do not forget to run "nc -lk
                        -p 31337" on your host beforehand''')

    args = parser.parse_args()

    my_pid = os.getpid()
    print(f"my pid is {my_pid}")

    if args.cgroup:
        mem_cgrp_path = os.path.join('/sys/fs/cgroup/memory', args.cgroup)
        if not os.path.exists(mem_cgrp_path):
            os.mkdir(mem_cgrp_path)

        with open(mem_cgrp_path + '/tasks', 'w') as f:
            f.write(f"{my_pid}")

    script_path = os.path.realpath(__file__)
    script_path = os.path.dirname(script_path)

    dyn_printk = 'dyndbg="file drivers/nvme/* +p"'
    qemu_cmd = [
        f"{script_path}/qemu/build/qemu-system-x86_64",
        '-display', 'none',
        '-chardev', 'stdio,mux=on,id=ch0',
        '-mon', 'chardev=ch0,mode=readline',

        "-enable-kvm", "-m", "1024",
        '-cpu', 'host',
        '-smp', '2',
        "-device", "e1000,netdev=net0",
        "-netdev", "user,id=net0,hostfwd=tcp::5551-:22",
        "-append", f"console=ttyS0 root=/dev/vda3 {dyn_printk}",
        "-kernel", f"{script_path}/linux/arch/x86_64/boot/bzImage",
        "-drive", f"file={script_path}/alpine.qcow2,if=virtio",
        "-gdb", f"tcp::1234",
    ]

    if args.tcp_serial:
        qemu_cmd += [
            '-chardev', 'socket,port=31337,host=10.0.2.2,id=ch1',
            '-serial', 'chardev:ch1',
        ]
    else:
        qemu_cmd += ['-serial', 'chardev:ch0']

    if args.vhost_scsi:
        qemu_cmd += ['-device',  'vhost-scsi-pci,wwpn=naa.000000000000000b,bus=pci.0,addr=0x6']
    elif not args.no_test_volume:
        qemu_cmd += ['-device',  'vhost-kernel-nvme,bus=pci.0,addr=0x5,serial=deadbeaf']


    gdbserver_cmd = [
        "gdbserver", "0.0.0.0:3333",
        qemu_cmd[0],
        subprocess.list2cmdline(qemu_cmd[1:])
    ]

    if args.gdbserver:
        command = gdbserver_cmd
    else:
        command = qemu_cmd

    print("launching:\n" + subprocess.list2cmdline(command))

    if args.dry_run:
        os.sys.exit(0)

    p = subprocess.Popen(command)
    p.wait()
    print("~~~ Goodbye ~~~")
    
if __name__ == "__main__":
    main()