Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Vitor Massaru Iha <vitor@massaru.org>
To:     kunit-dev@googlegroups.com
Cc:     linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org,
        brendanhiggins@google.com, keescook@chromium.org,
        davidgow@google.com, skhan@linuxfoundation.org,
        linux-kernel-mentees@lists.linuxfoundation.org
Subject: [RFC 1/3] kunit: tool: Add support root filesystem in kunit-tool
Date:   Wed, 15 Jul 2020 00:11:18 -0300
Message-Id: <20200715031120.1002016-2-vitor@massaru.org>
In-Reply-To: <20200715031120.1002016-1-vitor@massaru.org>
References: <20200715031120.1002016-1-vitor@massaru.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

This makes it possible to use KUnit tests as modules.
And with that the tests can run in userspace.

The filesystem was created using debootstrap:
   sudo debootstrap buster buster_rootfs

And change the owner of the root filesystem files
for your user:
   sudo chown -R $USER:$USER buster_rootfs

For the kunit-tool to correctly capture the test results,
uml_utilities must be installed on the host to halt uml.

Signed-off-by: Vitor Massaru Iha <vitor@massaru.org>
---
 tools/testing/kunit/kunit.py        |  37 ++++++++--
 tools/testing/kunit/kunit_kernel.py | 105 ++++++++++++++++++++++++----
 2 files changed, 121 insertions(+), 21 deletions(-)

diff --git a/tools/testing/kunit/kunit.py b/tools/testing/kunit/kunit.py
index 787b6d4ad716..6d8ba0215b90 100755
--- a/tools/testing/kunit/kunit.py
+++ b/tools/testing/kunit/kunit.py
@@ -23,16 +23,16 @@ import kunit_parser
 KunitResult = namedtuple('KunitResult', ['status','result','elapsed_time'])
 
 KunitConfigRequest = namedtuple('KunitConfigRequest',
-				['build_dir', 'make_options'])
+				['build_dir', 'uml_root_dir', 'make_options'])
 KunitBuildRequest = namedtuple('KunitBuildRequest',
-			       ['jobs', 'build_dir', 'alltests',
+			       ['jobs', 'build_dir', 'uml_root_dir', 'alltests',
 				'make_options'])
 KunitExecRequest = namedtuple('KunitExecRequest',
-			      ['timeout', 'build_dir', 'alltests'])
+			      ['timeout', 'build_dir', 'uml_root_dir', 'alltests'])
 KunitParseRequest = namedtuple('KunitParseRequest',
 			       ['raw_output', 'input_data'])
 KunitRequest = namedtuple('KunitRequest', ['raw_output','timeout', 'jobs',
-					   'build_dir', 'alltests',
+					   'build_dir', 'uml_root_dir', 'alltests',
 					   'make_options'])
 
 KernelDirectoryPath = sys.argv[0].split('tools/testing/kunit/')[0]
@@ -47,7 +47,6 @@ def create_default_kunitconfig():
 	if not os.path.exists(kunit_kernel.kunitconfig_path):
 		shutil.copyfile('arch/um/configs/kunit_defconfig',
 				kunit_kernel.kunitconfig_path)
-
 def get_kernel_root_path():
 	parts = sys.argv[0] if not __file__ else __file__
 	parts = os.path.realpath(parts).split('tools/testing/kunit')
@@ -58,10 +57,22 @@ def get_kernel_root_path():
 def config_tests(linux: kunit_kernel.LinuxSourceTree,
 		 request: KunitConfigRequest) -> KunitResult:
 	kunit_parser.print_with_timestamp('Configuring KUnit Kernel ...')
+	defconfig = False
 
 	config_start = time.time()
 	create_default_kunitconfig()
-	success = linux.build_reconfig(request.build_dir, request.make_options)
+
+	if request.uml_root_dir != None:
+		if os.path.exists(request.uml_root_dir):
+			kunit_kernel.uml_root_path = os.path.abspath(request.uml_root_dir)
+			defconfig = True
+		else:
+			config_end = time.time()
+			return KunitResult(KunitStatus.CONFIG_FAILURE,
+					'could not configure kernel',
+					config_end - config_start)
+
+	success = linux.build_reconfig(request.build_dir, defconfig, request.make_options)
 	config_end = time.time()
 	if not success:
 		return KunitResult(KunitStatus.CONFIG_FAILURE,
@@ -79,6 +90,7 @@ def build_tests(linux: kunit_kernel.LinuxSourceTree,
 	success = linux.build_um_kernel(request.alltests,
 					request.jobs,
 					request.build_dir,
+					request.uml_root_dir,
 					request.make_options)
 	build_end = time.time()
 	if not success:
@@ -97,7 +109,7 @@ def exec_tests(linux: kunit_kernel.LinuxSourceTree,
 	test_start = time.time()
 	result = linux.run_kernel(
 		timeout=None if request.alltests else request.timeout,
-		build_dir=request.build_dir)
+		build_dir=request.build_dir, uml_root_dir=request.uml_root_dir)
 
 	test_end = time.time()
 
@@ -130,12 +142,14 @@ def run_tests(linux: kunit_kernel.LinuxSourceTree,
 	run_start = time.time()
 
 	config_request = KunitConfigRequest(request.build_dir,
+					    request.uml_root_dir,
 					    request.make_options)
 	config_result = config_tests(linux, config_request)
 	if config_result.status != KunitStatus.SUCCESS:
 		return config_result
 
 	build_request = KunitBuildRequest(request.jobs, request.build_dir,
+					  request.uml_root_dir,
 					  request.alltests,
 					  request.make_options)
 	build_result = build_tests(linux, build_request)
@@ -143,6 +157,7 @@ def run_tests(linux: kunit_kernel.LinuxSourceTree,
 		return build_result
 
 	exec_request = KunitExecRequest(request.timeout, request.build_dir,
+					request.uml_root_dir,
 					request.alltests)
 	exec_result = exec_tests(linux, exec_request)
 	if exec_result.status != KunitStatus.SUCCESS:
@@ -168,6 +183,10 @@ def add_common_opts(parser):
 			    help='As in the make command, it specifies the build '
 			    'directory.',
                             type=str, default='.kunit', metavar='build_dir')
+	parser.add_argument('--uml_root_dir',
+			    help='To load modules, a root filesystem is '
+			    'required to install and load these modules.',
+                            type=str, default=None, metavar='uml_root_dir')
 	parser.add_argument('--make_options',
 			    help='X=Y make option, can be repeated.',
 			    action='append')
@@ -252,6 +271,7 @@ def main(argv, linux=None):
 				       cli_args.timeout,
 				       cli_args.jobs,
 				       cli_args.build_dir,
+				       cli_args.uml_root_dir,
 				       cli_args.alltests,
 				       cli_args.make_options)
 		result = run_tests(linux, request)
@@ -272,6 +292,7 @@ def main(argv, linux=None):
 			linux = kunit_kernel.LinuxSourceTree()
 
 		request = KunitConfigRequest(cli_args.build_dir,
+					     cli_args.uml_root_dir,
 					     cli_args.make_options)
 		result = config_tests(linux, request)
 		kunit_parser.print_with_timestamp((
@@ -295,6 +316,7 @@ def main(argv, linux=None):
 
 		request = KunitBuildRequest(cli_args.jobs,
 					    cli_args.build_dir,
+					    cli_args.uml_root_dir,
 					    cli_args.alltests,
 					    cli_args.make_options)
 		result = build_tests(linux, request)
@@ -319,6 +341,7 @@ def main(argv, linux=None):
 
 		exec_request = KunitExecRequest(cli_args.timeout,
 						cli_args.build_dir,
+						cli_args.uml_root_dir,
 						cli_args.alltests)
 		exec_result = exec_tests(linux, exec_request)
 		parse_request = KunitParseRequest(cli_args.raw_output,
diff --git a/tools/testing/kunit/kunit_kernel.py b/tools/testing/kunit/kunit_kernel.py
index 63dbda2d029f..d712f4619eaa 100644
--- a/tools/testing/kunit/kunit_kernel.py
+++ b/tools/testing/kunit/kunit_kernel.py
@@ -11,6 +11,7 @@ import logging
 import subprocess
 import os
 import signal
+import time
 
 from contextlib import ExitStack
 
@@ -19,7 +20,59 @@ import kunit_parser
 
 KCONFIG_PATH = '.config'
 kunitconfig_path = '.kunitconfig'
+X86_64_DEFCONFIG_PATH = 'arch/um/configs/x86_64_defconfig'
 BROKEN_ALLCONFIG_PATH = 'tools/testing/kunit/configs/broken_on_uml.config'
+uml_root_path = None
+
+make_cmd = {
+	'make': {
+		'command': ['make', 'ARCH=um'],
+		'msg_error': 'Could not call execute make: ',
+	},
+	'make_modules': {
+		'command': ['make', 'modules', 'ARCH=um'],
+		'msg_error': 'Could not call execute make modules: ',
+	},
+	'make_modules_install': {
+		'command': ['make', 'modules_install', 'ARCH=um'],
+		'msg_error': 'Could not call execute make modules_install: ',
+	}
+}
+
+def halt_uml():
+	try:
+		subprocess.call(['uml_mconsole', 'kunitid', 'halt'])
+	except OSError as e:
+		raise ConfigError('Could not call uml_mconsole ' + e)
+	except subprocess.CalledProcessError as e:
+			raise ConfigError(e.output)
+
+
+def enable_uml_modules_on_boot(output_command):
+	uml_modules_path = None
+	found_kernel_version = False
+	modules = []
+	for i in output_command.decode('utf-8').split():
+		if found_kernel_version:
+			kernel_version = i
+			uml_modules_path = os.path.join(uml_root_path,
+			      'lib/modules/', kernel_version, 'kernel/lib/')
+			break
+		if 'DEPMOD' in i:
+			found_kernel_version = True
+
+	try:
+		if os.path.exists(uml_modules_path):
+			modules = subprocess.check_output(['ls',
+					    uml_modules_path]).decode('utf-8').split()
+	except OSError as e:
+		raise ConfigError('Could not list directory ' + e)
+	except subprocess.CalledProcessError as e:
+			raise ConfigError(e.output)
+
+	with open(os.path.join(uml_root_path, 'etc/modules'), 'w') as f:
+		for i in modules:
+			f.write(i.replace('.ko', ''))
 
 class ConfigError(Exception):
 	"""Represents an error trying to configure the Linux kernel."""
@@ -70,20 +123,27 @@ class LinuxSourceTreeOperations(object):
 		kunit_parser.print_with_timestamp(
 			'Starting Kernel with all configs takes a few minutes...')
 
-	def make(self, jobs, build_dir, make_options):
-		command = ['make', 'ARCH=um', '--jobs=' + str(jobs)]
+	def make(self, cmd, jobs, build_dir, make_options):
+		command = make_cmd[cmd]['command'] + ['--jobs=' + str(jobs)]
+
 		if make_options:
 			command.extend(make_options)
 		if build_dir:
 			command += ['O=' + build_dir]
+
+		if cmd == 'make_modules_install':
+			command += ['INSTALL_MOD_PATH=' + uml_root_path]
+
 		try:
-			subprocess.check_output(command)
+			output = subprocess.check_output(command)
+			if cmd == 'make_modules_install':
+				 enable_uml_modules_on_boot(output)
 		except OSError as e:
-			raise BuildError('Could not call execute make: ' + e)
+			raise BuildError(make_cmd[cmd][msg_error] + e)
 		except subprocess.CalledProcessError as e:
 			raise BuildError(e.output)
 
-	def linux_bin(self, params, timeout, build_dir, outfile):
+	def linux_bin(self, params, timeout, build_dir, uml_root_dir, outfile):
 		"""Runs the Linux UML binary. Must be named 'linux'."""
 		linux_bin = './linux'
 		if build_dir:
@@ -92,7 +152,11 @@ class LinuxSourceTreeOperations(object):
 			process = subprocess.Popen([linux_bin] + params,
 						   stdout=output,
 						   stderr=subprocess.STDOUT)
-			process.wait(timeout)
+			if uml_root_dir:
+				time.sleep(timeout)
+				halt_uml()
+			else:
+				process.wait(timeout)
 
 
 def get_kconfig_path(build_dir):
@@ -132,11 +196,16 @@ class LinuxSourceTree(object):
 			return False
 		return True
 
-	def build_config(self, build_dir, make_options):
+	def build_config(self, build_dir, defconfig, make_options):
 		kconfig_path = get_kconfig_path(build_dir)
 		if build_dir and not os.path.exists(build_dir):
 			os.mkdir(build_dir)
 		self._kconfig.write_to_file(kconfig_path)
+
+		if defconfig:
+			with open(kconfig_path, 'a')  as fw:
+				with open(X86_64_DEFCONFIG_PATH, 'r') as fr:
+					fw.write(fr.read())
 		try:
 			self._ops.make_olddefconfig(build_dir, make_options)
 		except ConfigError as e:
@@ -144,7 +213,7 @@ class LinuxSourceTree(object):
 			return False
 		return self.validate_config(build_dir)
 
-	def build_reconfig(self, build_dir, make_options):
+	def build_reconfig(self, build_dir, defconfig, make_options):
 		"""Creates a new .config if it is not a subset of the .kunitconfig."""
 		kconfig_path = get_kconfig_path(build_dir)
 		if os.path.exists(kconfig_path):
@@ -153,28 +222,36 @@ class LinuxSourceTree(object):
 			if not self._kconfig.is_subset_of(existing_kconfig):
 				print('Regenerating .config ...')
 				os.remove(kconfig_path)
-				return self.build_config(build_dir, make_options)
+				return self.build_config(build_dir, defconfig, make_options)
 			else:
 				return True
 		else:
 			print('Generating .config ...')
-			return self.build_config(build_dir, make_options)
+			return self.build_config(build_dir, defconfig, make_options)
 
-	def build_um_kernel(self, alltests, jobs, build_dir, make_options):
+	def build_um_kernel(self, alltests, jobs, build_dir, uml_root_dir, make_options):
 		if alltests:
 			self._ops.make_allyesconfig()
 		try:
 			self._ops.make_olddefconfig(build_dir, make_options)
-			self._ops.make(jobs, build_dir, make_options)
+			self._ops.make('make', jobs, build_dir, make_options)
+			if uml_root_dir:
+				self._ops.make('make_modules', jobs, build_dir,
+						make_options)
+				self._ops.make('make_modules_install', jobs,
+						build_dir, make_options)
 		except (ConfigError, BuildError) as e:
 			logging.error(e)
 			return False
 		return self.validate_config(build_dir)
 
-	def run_kernel(self, args=[], build_dir='', timeout=None):
+	def run_kernel(self, args=[], build_dir='', uml_root_dir=None, timeout=None):
 		args.extend(['mem=1G'])
+		if uml_root_dir:
+			args.extend(['root=/dev/root', 'rootfstype=hostfs',
+				     'rootflags=' + uml_root_path, 'umid=kunitid'])
 		outfile = 'test.log'
-		self._ops.linux_bin(args, timeout, build_dir, outfile)
+		self._ops.linux_bin(args, timeout, build_dir, uml_root_dir, outfile)
 		subprocess.call(['stty', 'sane'])
 		with open(outfile, 'r') as file:
 			for line in file:
-- 
2.26.2