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