1# SPDX-License-Identifier: GPL-2.0
2#
3# Runs UML kernel, collects output, and handles errors.
4#
5# Copyright (C) 2019, Google LLC.
6# Author: Felix Guo <felixguoxiuping@gmail.com>
7# Author: Brendan Higgins <brendanhiggins@google.com>
8
9import importlib.abc
10import importlib.util
11import logging
12import subprocess
13import os
14import shlex
15import shutil
16import signal
17import threading
18from typing import Iterator, List, Optional, Tuple
19
20import kunit_config
21import kunit_parser
22import qemu_config
23
24KCONFIG_PATH = '.config'
25KUNITCONFIG_PATH = '.kunitconfig'
26OLD_KUNITCONFIG_PATH = 'last_used_kunitconfig'
27DEFAULT_KUNITCONFIG_PATH = 'tools/testing/kunit/configs/default.config'
28BROKEN_ALLCONFIG_PATH = 'tools/testing/kunit/configs/broken_on_uml.config'
29OUTFILE_PATH = 'test.log'
30ABS_TOOL_PATH = os.path.abspath(os.path.dirname(__file__))
31QEMU_CONFIGS_DIR = os.path.join(ABS_TOOL_PATH, 'qemu_configs')
32
33class ConfigError(Exception):
34	"""Represents an error trying to configure the Linux kernel."""
35
36
37class BuildError(Exception):
38	"""Represents an error trying to build the Linux kernel."""
39
40
41class LinuxSourceTreeOperations:
42	"""An abstraction over command line operations performed on a source tree."""
43
44	def __init__(self, linux_arch: str, cross_compile: Optional[str]):
45		self._linux_arch = linux_arch
46		self._cross_compile = cross_compile
47
48	def make_mrproper(self) -> None:
49		try:
50			subprocess.check_output(['make', 'mrproper'], stderr=subprocess.STDOUT)
51		except OSError as e:
52			raise ConfigError('Could not call make command: ' + str(e))
53		except subprocess.CalledProcessError as e:
54			raise ConfigError(e.output.decode())
55
56	def make_arch_qemuconfig(self, base_kunitconfig: kunit_config.Kconfig) -> None:
57		pass
58
59	def make_allyesconfig(self, build_dir: str, make_options) -> None:
60		raise ConfigError('Only the "um" arch is supported for alltests')
61
62	def make_olddefconfig(self, build_dir: str, make_options) -> None:
63		command = ['make', 'ARCH=' + self._linux_arch, 'O=' + build_dir, 'olddefconfig']
64		if self._cross_compile:
65			command += ['CROSS_COMPILE=' + self._cross_compile]
66		if make_options:
67			command.extend(make_options)
68		print('Populating config with:\n$', ' '.join(command))
69		try:
70			subprocess.check_output(command, stderr=subprocess.STDOUT)
71		except OSError as e:
72			raise ConfigError('Could not call make command: ' + str(e))
73		except subprocess.CalledProcessError as e:
74			raise ConfigError(e.output.decode())
75
76	def make(self, jobs, build_dir: str, make_options) -> None:
77		command = ['make', 'ARCH=' + self._linux_arch, 'O=' + build_dir, '--jobs=' + str(jobs)]
78		if make_options:
79			command.extend(make_options)
80		if self._cross_compile:
81			command += ['CROSS_COMPILE=' + self._cross_compile]
82		print('Building with:\n$', ' '.join(command))
83		try:
84			proc = subprocess.Popen(command,
85						stderr=subprocess.PIPE,
86						stdout=subprocess.DEVNULL)
87		except OSError as e:
88			raise BuildError('Could not call execute make: ' + str(e))
89		except subprocess.CalledProcessError as e:
90			raise BuildError(e.output)
91		_, stderr = proc.communicate()
92		if proc.returncode != 0:
93			raise BuildError(stderr.decode())
94		if stderr:  # likely only due to build warnings
95			print(stderr.decode())
96
97	def start(self, params: List[str], build_dir: str) -> subprocess.Popen:
98		raise RuntimeError('not implemented!')
99
100
101class LinuxSourceTreeOperationsQemu(LinuxSourceTreeOperations):
102
103	def __init__(self, qemu_arch_params: qemu_config.QemuArchParams, cross_compile: Optional[str]):
104		super().__init__(linux_arch=qemu_arch_params.linux_arch,
105				 cross_compile=cross_compile)
106		self._kconfig = qemu_arch_params.kconfig
107		self._qemu_arch = qemu_arch_params.qemu_arch
108		self._kernel_path = qemu_arch_params.kernel_path
109		self._kernel_command_line = qemu_arch_params.kernel_command_line + ' kunit_shutdown=reboot'
110		self._extra_qemu_params = qemu_arch_params.extra_qemu_params
111
112	def make_arch_qemuconfig(self, base_kunitconfig: kunit_config.Kconfig) -> None:
113		kconfig = kunit_config.parse_from_string(self._kconfig)
114		base_kunitconfig.merge_in_entries(kconfig)
115
116	def start(self, params: List[str], build_dir: str) -> subprocess.Popen:
117		kernel_path = os.path.join(build_dir, self._kernel_path)
118		qemu_command = ['qemu-system-' + self._qemu_arch,
119				'-nodefaults',
120				'-m', '1024',
121				'-kernel', kernel_path,
122				'-append', ' '.join(params + [self._kernel_command_line]),
123				'-no-reboot',
124				'-nographic',
125				'-serial', 'stdio'] + self._extra_qemu_params
126		# Note: shlex.join() does what we want, but requires python 3.8+.
127		print('Running tests with:\n$', ' '.join(shlex.quote(arg) for arg in qemu_command))
128		return subprocess.Popen(qemu_command,
129					stdin=subprocess.PIPE,
130					stdout=subprocess.PIPE,
131					stderr=subprocess.STDOUT,
132					text=True, errors='backslashreplace')
133
134class LinuxSourceTreeOperationsUml(LinuxSourceTreeOperations):
135	"""An abstraction over command line operations performed on a source tree."""
136
137	def __init__(self, cross_compile=None):
138		super().__init__(linux_arch='um', cross_compile=cross_compile)
139
140	def make_allyesconfig(self, build_dir: str, make_options) -> None:
141		kunit_parser.print_with_timestamp(
142			'Enabling all CONFIGs for UML...')
143		command = ['make', 'ARCH=um', 'O=' + build_dir, 'allyesconfig']
144		if make_options:
145			command.extend(make_options)
146		process = subprocess.Popen(
147			command,
148			stdout=subprocess.DEVNULL,
149			stderr=subprocess.STDOUT)
150		process.wait()
151		kunit_parser.print_with_timestamp(
152			'Disabling broken configs to run KUnit tests...')
153
154		with open(get_kconfig_path(build_dir), 'a') as config:
155			with open(BROKEN_ALLCONFIG_PATH, 'r') as disable:
156				config.write(disable.read())
157		kunit_parser.print_with_timestamp(
158			'Starting Kernel with all configs takes a few minutes...')
159
160	def start(self, params: List[str], build_dir: str) -> subprocess.Popen:
161		"""Runs the Linux UML binary. Must be named 'linux'."""
162		linux_bin = os.path.join(build_dir, 'linux')
163		return subprocess.Popen([linux_bin] + params,
164					   stdin=subprocess.PIPE,
165					   stdout=subprocess.PIPE,
166					   stderr=subprocess.STDOUT,
167					   text=True, errors='backslashreplace')
168
169def get_kconfig_path(build_dir: str) -> str:
170	return os.path.join(build_dir, KCONFIG_PATH)
171
172def get_kunitconfig_path(build_dir: str) -> str:
173	return os.path.join(build_dir, KUNITCONFIG_PATH)
174
175def get_old_kunitconfig_path(build_dir: str) -> str:
176	return os.path.join(build_dir, OLD_KUNITCONFIG_PATH)
177
178def get_outfile_path(build_dir: str) -> str:
179	return os.path.join(build_dir, OUTFILE_PATH)
180
181def get_source_tree_ops(arch: str, cross_compile: Optional[str]) -> LinuxSourceTreeOperations:
182	config_path = os.path.join(QEMU_CONFIGS_DIR, arch + '.py')
183	if arch == 'um':
184		return LinuxSourceTreeOperationsUml(cross_compile=cross_compile)
185	if os.path.isfile(config_path):
186		return get_source_tree_ops_from_qemu_config(config_path, cross_compile)[1]
187
188	options = [f[:-3] for f in os.listdir(QEMU_CONFIGS_DIR) if f.endswith('.py')]
189	raise ConfigError(arch + ' is not a valid arch, options are ' + str(sorted(options)))
190
191def get_source_tree_ops_from_qemu_config(config_path: str,
192					 cross_compile: Optional[str]) -> Tuple[
193							 str, LinuxSourceTreeOperations]:
194	# The module name/path has very little to do with where the actual file
195	# exists (I learned this through experimentation and could not find it
196	# anywhere in the Python documentation).
197	#
198	# Bascially, we completely ignore the actual file location of the config
199	# we are loading and just tell Python that the module lives in the
200	# QEMU_CONFIGS_DIR for import purposes regardless of where it actually
201	# exists as a file.
202	module_path = '.' + os.path.join(os.path.basename(QEMU_CONFIGS_DIR), os.path.basename(config_path))
203	spec = importlib.util.spec_from_file_location(module_path, config_path)
204	assert spec is not None
205	config = importlib.util.module_from_spec(spec)
206	# See https://github.com/python/typeshed/pull/2626 for context.
207	assert isinstance(spec.loader, importlib.abc.Loader)
208	spec.loader.exec_module(config)
209
210	if not hasattr(config, 'QEMU_ARCH'):
211		raise ValueError('qemu_config module missing "QEMU_ARCH": ' + config_path)
212	params: qemu_config.QemuArchParams = config.QEMU_ARCH  # type: ignore
213	return params.linux_arch, LinuxSourceTreeOperationsQemu(
214			params, cross_compile=cross_compile)
215
216class LinuxSourceTree:
217	"""Represents a Linux kernel source tree with KUnit tests."""
218
219	def __init__(
220	      self,
221	      build_dir: str,
222	      load_config=True,
223	      kunitconfig_path='',
224	      kconfig_add: Optional[List[str]]=None,
225	      arch=None,
226	      cross_compile=None,
227	      qemu_config_path=None) -> None:
228		signal.signal(signal.SIGINT, self.signal_handler)
229		if qemu_config_path:
230			self._arch, self._ops = get_source_tree_ops_from_qemu_config(
231					qemu_config_path, cross_compile)
232		else:
233			self._arch = 'um' if arch is None else arch
234			self._ops = get_source_tree_ops(self._arch, cross_compile)
235
236		if not load_config:
237			return
238
239		if kunitconfig_path:
240			if os.path.isdir(kunitconfig_path):
241				kunitconfig_path = os.path.join(kunitconfig_path, KUNITCONFIG_PATH)
242			if not os.path.exists(kunitconfig_path):
243				raise ConfigError(f'Specified kunitconfig ({kunitconfig_path}) does not exist')
244		else:
245			kunitconfig_path = get_kunitconfig_path(build_dir)
246			if not os.path.exists(kunitconfig_path):
247				shutil.copyfile(DEFAULT_KUNITCONFIG_PATH, kunitconfig_path)
248
249		self._kconfig = kunit_config.parse_file(kunitconfig_path)
250		if kconfig_add:
251			kconfig = kunit_config.parse_from_string('\n'.join(kconfig_add))
252			self._kconfig.merge_in_entries(kconfig)
253
254	def arch(self) -> str:
255		return self._arch
256
257	def clean(self) -> bool:
258		try:
259			self._ops.make_mrproper()
260		except ConfigError as e:
261			logging.error(e)
262			return False
263		return True
264
265	def validate_config(self, build_dir: str) -> bool:
266		kconfig_path = get_kconfig_path(build_dir)
267		validated_kconfig = kunit_config.parse_file(kconfig_path)
268		if self._kconfig.is_subset_of(validated_kconfig):
269			return True
270		invalid = self._kconfig.entries() - validated_kconfig.entries()
271		message = 'Not all Kconfig options selected in kunitconfig were in the generated .config.\n' \
272			  'This is probably due to unsatisfied dependencies.\n' \
273			  'Missing: ' + ', '.join([str(e) for e in invalid])
274		if self._arch == 'um':
275			message += '\nNote: many Kconfig options aren\'t available on UML. You can try running ' \
276				   'on a different architecture with something like "--arch=x86_64".'
277		logging.error(message)
278		return False
279
280	def build_config(self, build_dir: str, make_options) -> bool:
281		kconfig_path = get_kconfig_path(build_dir)
282		if build_dir and not os.path.exists(build_dir):
283			os.mkdir(build_dir)
284		try:
285			self._ops.make_arch_qemuconfig(self._kconfig)
286			self._kconfig.write_to_file(kconfig_path)
287			self._ops.make_olddefconfig(build_dir, make_options)
288		except ConfigError as e:
289			logging.error(e)
290			return False
291		if not self.validate_config(build_dir):
292			return False
293
294		old_path = get_old_kunitconfig_path(build_dir)
295		if os.path.exists(old_path):
296			os.remove(old_path)  # write_to_file appends to the file
297		self._kconfig.write_to_file(old_path)
298		return True
299
300	def _kunitconfig_changed(self, build_dir: str) -> bool:
301		old_path = get_old_kunitconfig_path(build_dir)
302		if not os.path.exists(old_path):
303			return True
304
305		old_kconfig = kunit_config.parse_file(old_path)
306		return old_kconfig.entries() != self._kconfig.entries()
307
308	def build_reconfig(self, build_dir: str, make_options) -> bool:
309		"""Creates a new .config if it is not a subset of the .kunitconfig."""
310		kconfig_path = get_kconfig_path(build_dir)
311		if not os.path.exists(kconfig_path):
312			print('Generating .config ...')
313			return self.build_config(build_dir, make_options)
314
315		existing_kconfig = kunit_config.parse_file(kconfig_path)
316		self._ops.make_arch_qemuconfig(self._kconfig)
317		if self._kconfig.is_subset_of(existing_kconfig) and not self._kunitconfig_changed(build_dir):
318			return True
319		print('Regenerating .config ...')
320		os.remove(kconfig_path)
321		return self.build_config(build_dir, make_options)
322
323	def build_kernel(self, alltests, jobs, build_dir: str, make_options) -> bool:
324		try:
325			if alltests:
326				self._ops.make_allyesconfig(build_dir, make_options)
327			self._ops.make_olddefconfig(build_dir, make_options)
328			self._ops.make(jobs, build_dir, make_options)
329		except (ConfigError, BuildError) as e:
330			logging.error(e)
331			return False
332		return self.validate_config(build_dir)
333
334	def run_kernel(self, args=None, build_dir='', filter_glob='', timeout=None) -> Iterator[str]:
335		if not args:
336			args = []
337		args.extend(['mem=1G', 'console=tty', 'kunit_shutdown=halt'])
338		if filter_glob:
339			args.append('kunit.filter_glob='+filter_glob)
340
341		process = self._ops.start(args, build_dir)
342		assert process.stdout is not None  # tell mypy it's set
343
344		# Enforce the timeout in a background thread.
345		def _wait_proc():
346			try:
347				process.wait(timeout=timeout)
348			except Exception as e:
349				print(e)
350				process.terminate()
351				process.wait()
352		waiter = threading.Thread(target=_wait_proc)
353		waiter.start()
354
355		output = open(get_outfile_path(build_dir), 'w')
356		try:
357			# Tee the output to the file and to our caller in real time.
358			for line in process.stdout:
359				output.write(line)
360				yield line
361		# This runs even if our caller doesn't consume every line.
362		finally:
363			# Flush any leftover output to the file
364			output.write(process.stdout.read())
365			output.close()
366			process.stdout.close()
367
368			waiter.join()
369			subprocess.call(['stty', 'sane'])
370
371	def signal_handler(self, unused_sig, unused_frame) -> None:
372		logging.error('Build interruption occurred. Cleaning console.')
373		subprocess.call(['stty', 'sane'])
374