1 # Copyright (c) 2019 Cisco and/or its affiliates.
2 # Licensed under the Apache License, Version 2.0 (the "License");
3 # you may not use this file except in compliance with the License.
4 # You may obtain a copy of the License at:
6 # http://www.apache.org/licenses/LICENSE-2.0
8 # Unless required by applicable law or agreed to in writing, software
9 # distributed under the License is distributed on an "AS IS" BASIS,
10 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
11 # See the License for the specific language governing permissions and
12 # limitations under the License.
14 """QEMU utilities library."""
18 from string import Template
19 from time import sleep
21 from robot.api import logger
22 from resources.libraries.python.Constants import Constants
23 from resources.libraries.python.DpdkUtil import DpdkUtil
24 from resources.libraries.python.DUTSetup import DUTSetup
25 from resources.libraries.python.OptionString import OptionString
26 from resources.libraries.python.VppConfigGenerator import VppConfigGenerator
27 from resources.libraries.python.VPPUtil import VPPUtil
28 from resources.libraries.python.ssh import exec_cmd, exec_cmd_no_error
29 from resources.libraries.python.topology import NodeType, Topology
31 __all__ = ["QemuUtils"]
34 class QemuUtils(object):
37 # Use one instance of class per tests.
38 ROBOT_LIBRARY_SCOPE = 'TEST CASE'
40 def __init__(self, node, qemu_id=1, smp=1, mem=512, vnf=None,
41 img=Constants.QEMU_VM_IMAGE):
42 """Initialize QemuUtil class.
44 :param node: Node to run QEMU on.
45 :param qemu_id: QEMU identifier.
46 :param smp: Number of virtual SMP units (cores).
47 :param mem: Amount of memory.
48 :param vnf: Network function workload.
49 :param img: QEMU disk image or kernel image path.
59 self._arch = Topology.get_node_arch(self._node)
60 dpdk_target = 'arm64-armv8a' if self._arch == 'aarch64' \
62 self._testpmd_path = '{path}/{dpdk_target}-linuxapp-gcc/app'\
63 .format(path=Constants.QEMU_VM_DPDK, dpdk_target=dpdk_target)
67 'port': 10021 + qemu_id,
68 'serial': 4555 + qemu_id,
73 if node['port'] != 22:
74 self._vm_info['host_port'] = node['port']
75 self._vm_info['host_username'] = node['username']
76 self._vm_info['host_password'] = node['password']
79 self._opt['qemu_id'] = qemu_id
80 self._opt['mem'] = int(mem)
81 self._opt['smp'] = int(smp)
82 self._opt['img'] = img
83 self._opt['vnf'] = vnf
86 self._temp['pidfile'] = '/var/run/qemu_{id}.pid'.format(id=qemu_id)
87 if img == Constants.QEMU_VM_IMAGE:
88 self._opt['vm_type'] = 'nestedvm'
89 self._temp['qmp'] = '/var/run/qmp_{id}.sock'.format(id=qemu_id)
90 self._temp['qga'] = '/var/run/qga_{id}.sock'.format(id=qemu_id)
91 elif img == Constants.QEMU_VM_KERNEL:
92 self._opt['img'], _ = exec_cmd_no_error(
94 'ls -1 {img}* | tail -1'.format(img=Constants.QEMU_VM_KERNEL),
95 message='Qemu Kernel VM image not found!')
96 self._opt['vm_type'] = 'kernelvm'
97 self._temp['log'] = '/tmp/serial_{id}.log'.format(id=qemu_id)
98 self._temp['ini'] = '/etc/vm_init_{id}.conf'.format(id=qemu_id)
99 self._opt['initrd'], _ = exec_cmd_no_error(
101 'ls -1 {initrd}* | tail -1'.format(
102 initrd=Constants.QEMU_VM_KERNEL_INITRD),
103 message='Qemu Kernel initrd image not found!')
105 raise RuntimeError('QEMU: Unknown VM image option: {}'.format(img))
106 # Computed parameters for QEMU command line.
107 self._params = OptionString(prefix='-')
110 def add_params(self):
111 """Set QEMU command line parameters."""
112 self.add_default_params()
113 if self._opt.get('vm_type', '') == 'nestedvm':
114 self.add_nestedvm_params()
115 elif self._opt.get('vm_type', '') == 'kernelvm':
116 self.add_kernelvm_params()
118 raise RuntimeError('QEMU: Unsupported VM type!')
120 def add_default_params(self):
121 """Set default QEMU command line parameters."""
122 self._params.add('daemonize')
123 self._params.add('nodefaults')
124 self._params.add_with_value('name', 'vnf{qemu},debug-threads=on'.format(
125 qemu=self._opt.get('qemu_id')))
126 self._params.add('no-user-config')
127 self._params.add_with_value('monitor', 'none')
128 self._params.add_with_value('display', 'none')
129 self._params.add_with_value('vga', 'none')
130 self._params.add('enable-kvm')
131 self._params.add_with_value('pidfile', self._temp.get('pidfile'))
132 self._params.add_with_value('cpu', 'host')
134 if self._arch == 'aarch64':
135 machine_args = 'virt,accel=kvm,usb=off,mem-merge=off,gic-version=3'
137 machine_args = 'pc,accel=kvm,usb=off,mem-merge=off'
138 self._params.add_with_value(
139 'machine', machine_args)
140 self._params.add_with_value(
141 'smp', '{smp},sockets=1,cores={smp},threads=1'.format(
142 smp=self._opt.get('smp')))
143 self._params.add_with_value(
144 'object', 'memory-backend-file,id=mem,size={mem}M,'
145 'mem-path=/dev/hugepages,share=on'.format(mem=self._opt.get('mem')))
146 self._params.add_with_value(
147 'm', '{mem}M'.format(mem=self._opt.get('mem')))
148 self._params.add_with_value('numa', 'node,memdev=mem')
149 self._params.add_with_value('balloon', 'none')
151 def add_nestedvm_params(self):
152 """Set NestedVM QEMU parameters."""
153 self._params.add_with_value(
154 'net', 'nic,macaddr=52:54:00:00:{qemu:02x}:ff'.format(
155 qemu=self._opt.get('qemu_id')))
156 self._params.add_with_value(
157 'net', 'user,hostfwd=tcp::{info[port]}-:22'.format(
159 locking = ',file.locking=off'
160 self._params.add_with_value(
161 'drive', 'file={img},format=raw,cache=none,if=virtio{locking}'.
162 format(img=self._opt.get('img'), locking=locking))
163 self._params.add_with_value(
164 'qmp', 'unix:{qmp},server,nowait'.format(qmp=self._temp.get('qmp')))
165 self._params.add_with_value(
166 'chardev', 'socket,host=127.0.0.1,port={info[serial]},'
167 'id=gnc0,server,nowait'.format(info=self._vm_info))
168 self._params.add_with_value('device', 'isa-serial,chardev=gnc0')
169 self._params.add_with_value(
170 'chardev', 'socket,path={qga},server,nowait,id=qga0'.format(
171 qga=self._temp.get('qga')))
172 self._params.add_with_value('device', 'isa-serial,chardev=qga0')
174 def add_kernelvm_params(self):
175 """Set KernelVM QEMU parameters."""
176 console = 'ttyAMA0' if self._arch == 'aarch64' else 'ttyS0'
177 self._params.add_with_value('serial', 'file:{log}'.format(
178 log=self._temp.get('log')))
179 self._params.add_with_value(
180 'fsdev', 'local,id=root9p,path=/,security_model=none')
181 self._params.add_with_value(
182 'device', 'virtio-9p-pci,fsdev=root9p,mount_tag=virtioroot')
183 self._params.add_with_value(
184 'kernel', '{img}'.format(img=self._opt.get('img')))
185 self._params.add_with_value(
186 'initrd', '{initrd}'.format(initrd=self._opt.get('initrd')))
187 self._params.add_with_value(
188 'append', '"ro rootfstype=9p rootflags=trans=virtio '
189 'root=virtioroot console={console} tsc=reliable '
190 'hugepages=256 init={init} fastboot"'.format(
191 console=console, init=self._temp.get('ini')))
193 def create_kernelvm_config_vpp(self, **kwargs):
194 """Create QEMU VPP config files.
196 :param kwargs: Key-value pairs to replace content of VPP configuration
200 startup = ('/etc/vpp/vm_startup_{id}.conf'.
201 format(id=self._opt.get('qemu_id')))
202 running = ('/etc/vpp/vm_running_{id}.exec'.
203 format(id=self._opt.get('qemu_id')))
205 self._temp['startup'] = startup
206 self._temp['running'] = running
207 self._opt['vnf_bin'] = ('/usr/bin/vpp -c {startup}'.
208 format(startup=startup))
210 # Create VPP startup configuration.
211 vpp_config = VppConfigGenerator()
212 vpp_config.set_node(self._node)
213 vpp_config.add_unix_nodaemon()
214 vpp_config.add_unix_cli_listen()
215 vpp_config.add_unix_exec(running)
216 vpp_config.add_socksvr()
217 vpp_config.add_cpu_main_core('0')
218 if self._opt.get('smp') > 1:
219 vpp_config.add_cpu_corelist_workers('1-{smp}'.format(
220 smp=self._opt.get('smp')-1))
221 vpp_config.add_dpdk_dev('0000:00:06.0', '0000:00:07.0')
222 vpp_config.add_dpdk_dev_default_rxq(kwargs['queues'])
223 vpp_config.add_dpdk_log_level('debug')
224 if not kwargs['jumbo_frames']:
225 vpp_config.add_dpdk_no_multi_seg()
226 vpp_config.add_dpdk_no_tx_checksum_offload()
227 vpp_config.add_plugin('disable', 'default')
228 vpp_config.add_plugin('enable', 'dpdk_plugin.so')
229 vpp_config.write_config(startup)
231 # Create VPP running configuration.
232 template = '{res}/{tpl}.exec'.format(res=Constants.RESOURCES_TPL_VM,
233 tpl=self._opt.get('vnf'))
234 exec_cmd_no_error(self._node, 'rm -f {running}'.format(running=running),
237 with open(template, 'r') as src_file:
238 src = Template(src_file.read())
240 self._node, "echo '{out}' | sudo tee {running}".format(
241 out=src.safe_substitute(**kwargs), running=running))
243 def create_kernelvm_config_testpmd_io(self, **kwargs):
244 """Create QEMU testpmd-io command line.
246 :param kwargs: Key-value pairs to construct command line parameters.
249 testpmd_cmd = DpdkUtil.get_testpmd_cmdline(
250 eal_corelist='0-{smp}'.format(smp=self._opt.get('smp') - 1),
254 pmd_rxq=kwargs['queues'],
255 pmd_txq=kwargs['queues'],
256 pmd_tx_offloads='0x0',
257 pmd_disable_hw_vlan=False,
258 pmd_nb_cores=str(self._opt.get('smp') - 1))
260 self._opt['vnf_bin'] = ('{testpmd_path}/{testpmd_cmd}'.
261 format(testpmd_path=self._testpmd_path,
262 testpmd_cmd=testpmd_cmd))
264 def create_kernelvm_config_testpmd_mac(self, **kwargs):
265 """Create QEMU testpmd-mac command line.
267 :param kwargs: Key-value pairs to construct command line parameters.
270 testpmd_cmd = DpdkUtil.get_testpmd_cmdline(
271 eal_corelist='0-{smp}'.format(smp=self._opt.get('smp') - 1),
276 pmd_eth_peer_0='0,{mac}'.format(mac=kwargs['vif1_mac']),
277 pmd_eth_peer_1='1,{mac}'.format(mac=kwargs['vif2_mac']),
278 pmd_rxq=kwargs['queues'],
279 pmd_txq=kwargs['queues'],
280 pmd_tx_offloads='0x0',
281 pmd_disable_hw_vlan=False,
282 pmd_nb_cores=str(self._opt.get('smp') - 1))
284 self._opt['vnf_bin'] = ('{testpmd_path}/{testpmd_cmd}'.
285 format(testpmd_path=self._testpmd_path,
286 testpmd_cmd=testpmd_cmd))
288 def create_kernelvm_init(self, **kwargs):
289 """Create QEMU init script.
291 :param kwargs: Key-value pairs to replace content of init startup file.
294 template = '{res}/init.sh'.format(res=Constants.RESOURCES_TPL_VM)
295 init = self._temp.get('ini')
297 self._node, 'rm -f {init}'.format(init=init), sudo=True)
299 with open(template, 'r') as src_file:
300 src = Template(src_file.read())
302 self._node, "echo '{out}' | sudo tee {init}".format(
303 out=src.safe_substitute(**kwargs), init=init))
305 self._node, "chmod +x {init}".format(init=init), sudo=True)
307 def configure_kernelvm_vnf(self, **kwargs):
308 """Create KernelVM VNF configurations.
310 :param kwargs: Key-value pairs for templating configs.
313 if 'vpp' in self._opt.get('vnf'):
314 self.create_kernelvm_config_vpp(**kwargs)
315 elif 'testpmd_io' in self._opt.get('vnf'):
316 self.create_kernelvm_config_testpmd_io(**kwargs)
317 elif 'testpmd_mac' in self._opt.get('vnf'):
318 self.create_kernelvm_config_testpmd_mac(**kwargs)
320 raise RuntimeError('QEMU: Unsupported VNF!')
321 self.create_kernelvm_init(vnf_bin=self._opt['vnf_bin'])
323 def get_qemu_pids(self):
324 """Get QEMU CPU pids.
326 :returns: List of QEMU CPU pids.
329 command = ("grep -rwl 'CPU' /proc/$(sudo cat {pidfile})/task/*/comm ".
330 format(pidfile=self._temp.get('pidfile')))
331 command += (r"| xargs dirname | sed -e 's/\/.*\///g' | uniq")
333 stdout, _ = exec_cmd_no_error(self._node, command)
334 return stdout.splitlines()
336 def qemu_set_affinity(self, *host_cpus):
337 """Set qemu affinity by getting thread PIDs via QMP and taskset to list
338 of CPU cores. Function tries to execute 3 times to avoid race condition
339 in getting thread PIDs.
341 :param host_cpus: List of CPU cores.
342 :type host_cpus: list
346 qemu_cpus = self.get_qemu_pids()
348 if len(qemu_cpus) != len(host_cpus):
351 for qemu_cpu, host_cpu in zip(qemu_cpus, host_cpus):
352 command = ('taskset -pc {host_cpu} {thread}'.
353 format(host_cpu=host_cpu, thread=qemu_cpu))
354 message = ('QEMU: Set affinity failed on {host}!'.
355 format(host=self._node['host']))
356 exec_cmd_no_error(self._node, command, sudo=True,
359 except (RuntimeError, ValueError):
364 raise RuntimeError('Failed to set Qemu threads affinity!')
366 def qemu_set_scheduler_policy(self):
367 """Set scheduler policy to SCHED_RR with priority 1 for all Qemu CPU
370 :raises RuntimeError: Set scheduler policy failed.
373 qemu_cpus = self.get_qemu_pids()
375 for qemu_cpu in qemu_cpus:
376 command = ('chrt -r -p 1 {thread}'.
377 format(thread=qemu_cpu))
378 message = ('QEMU: Set SCHED_RR failed on {host}'.
379 format(host=self._node['host']))
380 exec_cmd_no_error(self._node, command, sudo=True,
382 except (RuntimeError, ValueError):
386 def qemu_add_vhost_user_if(self, socket, server=True, jumbo_frames=False,
387 queue_size=None, queues=1):
388 """Add Vhost-user interface.
390 :param socket: Path of the unix socket.
391 :param server: If True the socket shall be a listening socket.
392 :param jumbo_frames: Set True if jumbo frames are used in the test.
393 :param queue_size: Vring queue size.
394 :param queues: Number of queues.
397 :type jumbo_frames: bool
398 :type queue_size: int
402 self._params.add_with_value(
403 'chardev', 'socket,id=char{vhost},path={socket}{server}'.format(
404 vhost=self._vhost_id, socket=socket,
405 server=',server' if server is True else ''))
406 self._params.add_with_value(
407 'netdev', 'vhost-user,id=vhost{vhost},chardev=char{vhost},'
408 'queues={queues}'.format(vhost=self._vhost_id, queues=queues))
409 mac = ('52:54:00:00:{qemu:02x}:{vhost:02x}'.
410 format(qemu=self._opt.get('qemu_id'), vhost=self._vhost_id))
411 queue_size = ('rx_queue_size={queue_size},tx_queue_size={queue_size}'.
412 format(queue_size=queue_size)) if queue_size else ''
413 mbuf = 'on,host_mtu=9200'
414 self._params.add_with_value(
415 'device', 'virtio-net-pci,netdev=vhost{vhost},mac={mac},'
416 'addr={addr}.0,mq=on,vectors={vectors},csum=off,gso=off,'
417 'guest_tso4=off,guest_tso6=off,guest_ecn=off,mrg_rxbuf={mbuf},'
418 '{queue_size}'.format(
419 addr=self._vhost_id+5, vhost=self._vhost_id, mac=mac,
420 mbuf=mbuf if jumbo_frames else 'off', queue_size=queue_size,
421 vectors=(2 * queues + 2)))
423 # Add interface MAC and socket to the node dict.
424 if_data = {'mac_address': mac, 'socket': socket}
425 if_name = 'vhost{vhost}'.format(vhost=self._vhost_id)
426 self._vm_info['interfaces'][if_name] = if_data
427 # Add socket to temporary file list.
428 self._temp[if_name] = socket
430 def _qemu_qmp_exec(self, cmd):
431 """Execute QMP command.
433 QMP is JSON based protocol which allows to control QEMU instance.
435 :param cmd: QMP command to execute.
437 :returns: Command output in python representation of JSON format. The
438 { "return": {} } response is QMP's success response. An error
439 response will contain the "error" keyword instead of "return".
441 # To enter command mode, the qmp_capabilities command must be issued.
442 command = ('echo "{{ \\"execute\\": \\"qmp_capabilities\\" }}'
443 '{{ \\"execute\\": \\"{cmd}\\" }}" | '
444 'sudo -S socat - UNIX-CONNECT:{qmp}'.
445 format(cmd=cmd, qmp=self._temp.get('qmp')))
446 message = ('QMP execute "{cmd}" failed on {host}'.
447 format(cmd=cmd, host=self._node['host']))
448 stdout, _ = exec_cmd_no_error(
449 self._node, command, sudo=False, message=message)
451 # Skip capabilities negotiation messages.
452 out_list = stdout.splitlines()
453 if len(out_list) < 3:
455 'Invalid QMP output on {host}'.format(host=self._node['host']))
456 return json.loads(out_list[2])
458 def _qemu_qga_flush(self):
459 """Flush the QGA parser state."""
460 command = ('(printf "\xFF"; sleep 1) | '
461 'sudo -S socat - UNIX-CONNECT:{qga}'.
462 format(qga=self._temp.get('qga')))
463 message = ('QGA flush failed on {host}'.format(host=self._node['host']))
464 stdout, _ = exec_cmd_no_error(
465 self._node, command, sudo=False, message=message)
467 return json.loads(stdout.split('\n', 1)[0]) if stdout else dict()
469 def _qemu_qga_exec(self, cmd):
470 """Execute QGA command.
472 QGA provide access to a system-level agent via standard QMP commands.
474 :param cmd: QGA command to execute.
477 command = ('(echo "{{ \\"execute\\": \\"{cmd}\\" }}"; sleep 1) | '
478 'sudo -S socat - UNIX-CONNECT:{qga}'.
479 format(cmd=cmd, qga=self._temp.get('qga')))
480 message = ('QGA execute "{cmd}" failed on {host}'.
481 format(cmd=cmd, host=self._node['host']))
482 stdout, _ = exec_cmd_no_error(
483 self._node, command, sudo=False, message=message)
485 return json.loads(stdout.split('\n', 1)[0]) if stdout else dict()
487 def _wait_until_vm_boot(self):
488 """Wait until QEMU with NestedVM is booted."""
489 if self._opt.get('vm_type') == 'nestedvm':
490 self._wait_until_nestedvm_boot()
491 self._update_vm_interfaces()
492 elif self._opt.get('vm_type') == 'kernelvm':
493 self._wait_until_kernelvm_boot()
495 raise RuntimeError('QEMU: Unsupported VM type!')
497 def _wait_until_nestedvm_boot(self, retries=12):
498 """Wait until QEMU with NestedVM is booted.
500 First try to flush qga until there is output.
501 Then ping QEMU guest agent each 5s until VM booted or timeout.
503 :param retries: Number of retries with 5s between trials.
506 for _ in range(retries):
509 out = self._qemu_qga_flush()
511 logger.trace('QGA qga flush unexpected output {out}'.
513 # Empty output - VM not booted yet
519 raise RuntimeError('QEMU: Timeout, VM not booted on {host}!'.
520 format(host=self._node['host']))
521 for _ in range(retries):
524 out = self._qemu_qga_exec('guest-ping')
526 logger.trace('QGA guest-ping unexpected output {out}'.
528 # Empty output - VM not booted yet.
531 # Non-error return - VM booted.
532 elif out.get('return') is not None:
534 # Skip error and wait.
535 elif out.get('error') is not None:
538 # If there is an unexpected output from QGA guest-info, try
539 # again until timeout.
540 logger.trace('QGA guest-ping unexpected output {out}'.
543 raise RuntimeError('QEMU: Timeout, VM not booted on {host}!'.
544 format(host=self._node['host']))
546 def _wait_until_kernelvm_boot(self, retries=60):
547 """Wait until QEMU KernelVM is booted.
549 :param retries: Number of retries.
552 vpp_ver = VPPUtil.vpp_show_version(self._node)
554 for _ in range(retries):
555 command = ('tail -1 {log}'.format(log=self._temp.get('log')))
558 stdout, _ = exec_cmd_no_error(self._node, command, sudo=True)
562 if vpp_ver in stdout or 'Press enter to exit' in stdout:
564 if 'reboot: Power down' in stdout:
565 raise RuntimeError('QEMU: NF failed to run on {host}!'.
566 format(host=self._node['host']))
568 raise RuntimeError('QEMU: Timeout, VM not booted on {host}!'.
569 format(host=self._node['host']))
571 def _update_vm_interfaces(self):
572 """Update interface names in VM node dict."""
573 # Send guest-network-get-interfaces command via QGA, output example:
574 # {"return": [{"name": "eth0", "hardware-address": "52:54:00:00:04:01"},
575 # {"name": "eth1", "hardware-address": "52:54:00:00:04:02"}]}.
576 out = self._qemu_qga_exec('guest-network-get-interfaces')
577 interfaces = out.get('return')
580 raise RuntimeError('Get VM interface list failed on {host}'.
581 format(host=self._node['host']))
582 # Create MAC-name dict.
583 for interface in interfaces:
584 if 'hardware-address' not in interface:
586 mac_name[interface['hardware-address']] = interface['name']
587 # Match interface by MAC and save interface name.
588 for interface in self._vm_info['interfaces'].values():
589 mac = interface.get('mac_address')
590 if_name = mac_name.get(mac)
593 'Interface name for MAC {mac} not found'.format(mac=mac))
595 interface['name'] = if_name
597 def qemu_start(self):
598 """Start QEMU and wait until VM boot.
600 :returns: VM node info.
603 cmd_opts = OptionString()
604 cmd_opts.add('{bin_path}/qemu-system-{arch}'.format(
605 bin_path=Constants.QEMU_BIN_PATH, arch=self._arch))
606 cmd_opts.extend(self._params)
607 message = ('QEMU: Start failed on {host}!'.
608 format(host=self._node['host']))
610 DUTSetup.check_huge_page(
611 self._node, '/dev/hugepages', self._opt.get('mem'))
614 self._node, cmd_opts, timeout=300, sudo=True, message=message)
615 self._wait_until_vm_boot()
622 """Kill qemu process."""
623 exec_cmd(self._node, 'chmod +r {pidfile}'.
624 format(pidfile=self._temp.get('pidfile')), sudo=True)
625 exec_cmd(self._node, 'kill -SIGKILL $(cat {pidfile})'.
626 format(pidfile=self._temp.get('pidfile')), sudo=True)
628 for value in self._temp.values():
629 exec_cmd(self._node, 'cat {value}'.format(value=value), sudo=True)
630 exec_cmd(self._node, 'rm -f {value}'.format(value=value), sudo=True)
632 def qemu_kill_all(self):
633 """Kill all qemu processes on DUT node if specified."""
634 exec_cmd(self._node, 'pkill -SIGKILL qemu', sudo=True)
636 for value in self._temp.values():
637 exec_cmd(self._node, 'cat {value}'.format(value=value), sudo=True)
638 exec_cmd(self._node, 'rm -f {value}'.format(value=value), sudo=True)
640 def qemu_version(self):
641 """Return Qemu version.
643 :returns: Qemu version.
646 command = ('{bin_path}/qemu-system-{arch} --version'.format(
647 bin_path=Constants.QEMU_BIN_PATH,
650 stdout, _ = exec_cmd_no_error(self._node, command, sudo=True)
651 return match(r'QEMU emulator version ([\d.]*)', stdout).group(1)