Merge tag 'linux-kselftest-kunit-5.20-rc1' of...

Merge tag 'linux-kselftest-kunit-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull KUnit updates from Shuah Khan:
 "This consists of several fixes and an important feature to discourage
  running KUnit tests on production systems. Running tests on a
  production system could leave the system in a bad state.

  Summary:

   - Add a new taint type, TAINT_TEST to signal that a test has been
     run.

     This should discourage people from running these tests on
     production systems, and to make it easier to tell if tests have
     been run accidentally (by loading the wrong configuration, etc)

   - Several documentation and tool enhancements and fixes"

* tag 'linux-kselftest-kunit-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (29 commits)
  Documentation: KUnit: Fix example with compilation error
  Documentation: kunit: Add CLI args for kunit_tool
  kcsan: test: Add a .kunitconfig to run KCSAN tests
  kunit: executor: Fix a memory leak on failure in kunit_filter_tests
  clk: explicitly disable CONFIG_UML_PCI_OVER_VIRTIO in .kunitconfig
  mmc: sdhci-of-aspeed: test: Use kunit_test_suite() macro
  nitro_enclaves: test: Use kunit_test_suite() macro
  thunderbolt: test: Use kunit_test_suite() macro
  kunit: flatten kunit_suite*** to kunit_suite** in .kunit_test_suites
  kunit: unify module and builtin suite definitions
  selftest: Taint kernel when test module loaded
  module: panic: Taint the kernel when selftest modules load
  Documentation: kunit: fix example run_kunit func to allow spaces in args
  Documentation: kunit: Cleanup run_wrapper, fix x-ref
  kunit: test.h: fix a kernel-doc markup
  kunit: tool: Enable virtio/PCI by default on UML
  kunit: tool: make --kunitconfig repeatable, blindly concat
  kunit: add coverage_uml.config to enable GCOV on UML
  kunit: tool: refactor internal kconfig handling, allow overriding
  kunit: tool: introduce --qemu_args
  ...

Documentation/admin-guide/tainted-kernels.rst

@@ -100,6 +100,7 @@ Bit  Log  Number  Reason that got the kernel tainted
  15  _/K   32768  kernel has been live patched
  16  _/X   65536  auxiliary taint, defined for and used by distros
  17  _/T  131072  kernel was built with the struct randomization plugin
+ 18  _/N  262144  an in-kernel test has been run
 ===  ===  ======  ========================================================
 
 Note: The character ``_`` is representing a blank in this table to make reading

Documentation/dev-tools/kselftest.rst

@@ -275,6 +275,14 @@ assist writing kernel modules that are for use with kselftest:
 - ``tools/testing/selftests/kselftest_module.h``
 - ``tools/testing/selftests/kselftest/module.sh``
 
+Note that test modules should taint the kernel with TAINT_TEST. This will
+happen automatically for modules which are in the ``tools/testing/``
+directory, or for modules which use the ``kselftest_module.h`` header above.
+Otherwise, you'll need to add ``MODULE_INFO(test, "Y")`` to your module
+source. selftests which do not load modules typically should not taint the
+kernel, but in cases where a non-test module is loaded, TEST_TAINT can be
+applied from userspace by writing to ``/proc/sys/kernel/tainted``.
+
 How to use
 ----------
 
@@ -333,6 +341,7 @@ A bare bones test module might look like this:
    KSTM_MODULE_LOADERS(test_foo);
    MODULE_AUTHOR("John Developer <jd@fooman.org>");
    MODULE_LICENSE("GPL");
+   MODULE_INFO(test, "Y");
 
 Example test script
 -------------------

Documentation/dev-tools/kunit/run_wrapper.rst

@@ -192,6 +192,21 @@ via UML. To run tests on qemu, by default it requires two flags:
     if we have downloaded the microblaze toolchain from the 0-day
     website to a directory in our home directory called toolchains.
 
+This means that for most architectures, running under qemu is as simple as:
+
+.. code-block:: bash
+
+	./tools/testing/kunit/kunit.py run --arch=x86_64
+
+When cross-compiling, we'll likely need to specify a different toolchain, for
+example:
+
+.. code-block:: bash
+
+	./tools/testing/kunit/kunit.py run \
+		--arch=s390 \
+		--cross_compile=s390x-linux-gnu-
+
 If we want to run KUnit tests on an architecture not supported by
 the ``--arch`` flag, or want to run KUnit tests on qemu using a
 non-default configuration; then we can write our own``QemuConfig``.
@@ -214,14 +229,11 @@ as
 		--jobs=12 \
 		--qemu_config=./tools/testing/kunit/qemu_configs/x86_64.py
 
-To run existing KUnit tests on non-UML architectures, see:
-Documentation/dev-tools/kunit/non_uml.rst.
-
 Command-Line Arguments
 ======================
 
 kunit_tool has a number of other command-line arguments which can
-be useful for our test environment. Below the most commonly used
+be useful for our test environment. Below are the most commonly used
 command line arguments:
 
 - ``--help``: Lists all available options. To list common options,
@@ -245,3 +257,64 @@ command line arguments:
             added or modified. Instead, enable all tests
             which have satisfied dependencies by adding
             ``CONFIG_KUNIT_ALL_TESTS=y`` to your ``.kunitconfig``.
+
+- ``--kunitconfig``: Specifies the path or the directory of the ``.kunitconfig``
+  file. For example:
+
+  - ``lib/kunit/.kunitconfig`` can be the path of the file.
+
+  - ``lib/kunit`` can be the directory in which the file is located.
+
+  This file is used to build and run with a predefined set of tests
+  and their dependencies. For example, to run tests for a given subsystem.
+
+- ``--kconfig_add``: Specifies additional configuration options to be
+  appended to the ``.kunitconfig`` file. For example:
+
+  .. code-block::
+
+	./tools/testing/kunit/kunit.py run --kconfig_add CONFIG_KASAN=y
+
+- ``--arch``: Runs tests on the specified architecture. The architecture
+  argument is same as the Kbuild ARCH environment variable.
+  For example, i386, x86_64, arm, um, etc. Non-UML architectures run on qemu.
+  Default is `um`.
+
+- ``--cross_compile``: Specifies the Kbuild toolchain. It passes the
+  same argument as passed to the ``CROSS_COMPILE`` variable used by
+  Kbuild. This will be the prefix for the toolchain
+  binaries such as GCC. For example:
+
+  - ``sparc64-linux-gnu-`` if we have the sparc toolchain installed on
+    our system.
+
+  - ``$HOME/toolchains/microblaze/gcc-9.2.0-nolibc/microblaze-linux/bin/microblaze-linux``
+    if we have downloaded the microblaze toolchain from the 0-day
+    website to a specified path in our home directory called toolchains.
+
+- ``--qemu_config``: Specifies the path to a file containing a
+  custom qemu architecture definition. This should be a python file
+  containing a `QemuArchParams` object.
+
+- ``--qemu_args``: Specifies additional qemu arguments, for example, ``-smp 8``.
+
+- ``--jobs``: Specifies the number of jobs (commands) to run simultaneously.
+  By default, this is set to the number of cores on your system.
+
+- ``--timeout``: Specifies the maximum number of seconds allowed for all tests to run.
+  This does not include the time taken to build the tests.
+
+- ``--kernel_args``: Specifies additional kernel command-line arguments. May be repeated.
+
+- ``--run_isolated``: If set, boots the kernel for each individual suite/test.
+  This is useful for debugging a non-hermetic test, one that
+  might pass/fail based on what ran before it.
+
+- ``--raw_output``: If set, generates unformatted output from kernel. Possible options are:
+
+   - ``all``: To view the full kernel output, use ``--raw_output=all``.
+
+   - ``kunit``: This is the default option and filters to KUnit output. Use ``--raw_output`` or ``--raw_output=kunit``.
+
+- ``--json``: If set, stores the test results in a JSON format and prints to `stdout` or
+  saves to a file if a filename is specified.

Documentation/dev-tools/kunit/running_tips.rst

@@ -15,7 +15,7 @@ It can be handy to create a bash function like:
 .. code-block:: bash
 
 	function run_kunit() {
-	  ( cd "$(git rev-parse --show-toplevel)" && ./tools/testing/kunit/kunit.py run $@ )
+	  ( cd "$(git rev-parse --show-toplevel)" && ./tools/testing/kunit/kunit.py run "$@" )
 	}
 
 .. note::
@@ -123,8 +123,7 @@ Putting it together into a copy-pastable sequence of commands:
 .. code-block:: bash
 
 	# Append coverage options to the current config
-	$ echo -e "CONFIG_DEBUG_KERNEL=y\nCONFIG_DEBUG_INFO=y\nCONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y\nCONFIG_GCOV=y" >> .kunit/.kunitconfig
-	$ ./tools/testing/kunit/kunit.py run
+	$ ./tools/testing/kunit/kunit.py run --kunitconfig=.kunit/ --kunitconfig=tools/testing/kunit/configs/coverage_uml.config
 	# Extract the coverage information from the build dir (.kunit/)
 	$ lcov -t "my_kunit_tests" -o coverage.info -c -d .kunit/
 

Documentation/dev-tools/kunit/usage.rst

@@ -505,7 +505,7 @@ By reusing the same ``cases`` array from above, we can write the test as a
 		const char *str;
 		const char *sha1;
 	};
-	struct sha1_test_case cases[] = {
+	const struct sha1_test_case cases[] = {
 		{
 			.str = "hello world",
 			.sha1 = "2aae6c35c94fcfb415dbe95f408b9ce91ee846ed",

drivers/clk/.kunitconfig

@@ -2,3 +2,4 @@ CONFIG_KUNIT=y
 CONFIG_COMMON_CLK=y
 CONFIG_CLK_KUNIT_TEST=y
 CONFIG_CLK_GATE_KUNIT_TEST=y
+CONFIG_UML_PCI_OVER_VIRTIO=n

drivers/mmc/host/Kconfig

@@ -169,8 +169,9 @@ config MMC_SDHCI_OF_ASPEED
 	  If unsure, say N.
 
 config MMC_SDHCI_OF_ASPEED_TEST
-	bool "Tests for the ASPEED SDHCI driver"
-	depends on MMC_SDHCI_OF_ASPEED && KUNIT=y
+	bool "Tests for the ASPEED SDHCI driver" if !KUNIT_ALL_TESTS
+	depends on MMC_SDHCI_OF_ASPEED && KUNIT
+	default KUNIT_ALL_TESTS
 	help
 	  Enable KUnit tests for the ASPEED SDHCI driver. Select this
 	  option only if you will boot the kernel for the purpose of running

drivers/mmc/host/sdhci-of-aspeed-test.c

@@ -96,10 +96,4 @@ static struct kunit_suite aspeed_sdhci_test_suite = {
 	.test_cases = aspeed_sdhci_test_cases,
 };
 
-static struct kunit_suite *aspeed_sdc_test_suite_array[] = {
-	&aspeed_sdhci_test_suite,
-	NULL,
-};
-
-static struct kunit_suite **aspeed_sdc_test_suites
-	__used __section(".kunit_test_suites") = aspeed_sdc_test_suite_array;
+kunit_test_suite(aspeed_sdhci_test_suite);

drivers/mmc/host/sdhci-of-aspeed.c

@@ -606,25 +606,6 @@ static struct platform_driver aspeed_sdc_driver = {
 
 #if defined(CONFIG_MMC_SDHCI_OF_ASPEED_TEST)
 #include "sdhci-of-aspeed-test.c"
-
-static inline int aspeed_sdc_tests_init(void)
-{
-	return __kunit_test_suites_init(aspeed_sdc_test_suites);
-}
-
-static inline void aspeed_sdc_tests_exit(void)
-{
-	__kunit_test_suites_exit(aspeed_sdc_test_suites);
-}
-#else
-static inline int aspeed_sdc_tests_init(void)
-{
-	return 0;
-}
-
-static inline void aspeed_sdc_tests_exit(void)
-{
-}
 #endif
 
 static int __init aspeed_sdc_init(void)
@@ -637,18 +618,7 @@ static int __init aspeed_sdc_init(void)
 
 	rc = platform_driver_register(&aspeed_sdc_driver);
 	if (rc < 0)
-		goto cleanup_sdhci;
-
-	rc = aspeed_sdc_tests_init();
-	if (rc < 0) {
-		platform_driver_unregister(&aspeed_sdc_driver);
-		goto cleanup_sdhci;
-	}
-
-	return 0;
-
-cleanup_sdhci:
-	platform_driver_unregister(&aspeed_sdhci_driver);
+		platform_driver_unregister(&aspeed_sdhci_driver);
 
 	return rc;
 }
@@ -656,8 +626,6 @@ module_init(aspeed_sdc_init);
 
 static void __exit aspeed_sdc_exit(void)
 {
-	aspeed_sdc_tests_exit();
-
 	platform_driver_unregister(&aspeed_sdc_driver);
 	platform_driver_unregister(&aspeed_sdhci_driver);
 }

drivers/thunderbolt/Kconfig

@@ -28,8 +28,10 @@ config USB4_DEBUGFS_WRITE
 	  this for production systems or distro kernels.
 
 config USB4_KUNIT_TEST
-	bool "KUnit tests"
-	depends on KUNIT=y
+	bool "KUnit tests" if !KUNIT_ALL_TESTS
+	depends on (USB4=m || KUNIT=y)
+	depends on KUNIT
+	default KUNIT_ALL_TESTS
 
 config USB4_DMA_TEST
 	tristate "DMA traffic test driver"

drivers/thunderbolt/domain.c

@@ -872,7 +872,6 @@ int tb_domain_init(void)
 {
 	int ret;
 
-	tb_test_init();
 	tb_debugfs_init();
 	tb_acpi_init();
 
@@ -890,7 +889,6 @@ int tb_domain_init(void)
 err_acpi:
 	tb_acpi_exit();
 	tb_debugfs_exit();
-	tb_test_exit();
 
 	return ret;
 }
@@ -903,5 +901,4 @@ void tb_domain_exit(void)
 	tb_xdomain_exit();
 	tb_acpi_exit();
 	tb_debugfs_exit();
-	tb_test_exit();
 }

drivers/thunderbolt/tb.h

@@ -1271,12 +1271,4 @@ static inline void tb_service_debugfs_init(struct tb_service *svc) { }
 static inline void tb_service_debugfs_remove(struct tb_service *svc) { }
 #endif
 
-#ifdef CONFIG_USB4_KUNIT_TEST
-int tb_test_init(void);
-void tb_test_exit(void);
-#else
-static inline int tb_test_init(void) { return 0; }
-static inline void tb_test_exit(void) { }
-#endif
-
 #endif

drivers/thunderbolt/test.c

@@ -2817,14 +2817,4 @@ static struct kunit_suite tb_test_suite = {
 	.test_cases = tb_test_cases,
 };
 
-static struct kunit_suite *tb_test_suites[] = { &tb_test_suite, NULL };
-
-int tb_test_init(void)
-{
-	return __kunit_test_suites_init(tb_test_suites);
-}
-
-void tb_test_exit(void)
-{
-	return __kunit_test_suites_exit(tb_test_suites);
-}
+kunit_test_suite(tb_test_suite);

drivers/virt/nitro_enclaves/Kconfig

@@ -16,8 +16,9 @@ config NITRO_ENCLAVES
 	  The module will be called nitro_enclaves.
 
 config NITRO_ENCLAVES_MISC_DEV_TEST
-	bool "Tests for the misc device functionality of the Nitro Enclaves"
-	depends on NITRO_ENCLAVES && KUNIT=y
+	bool "Tests for the misc device functionality of the Nitro Enclaves" if !KUNIT_ALL_TESTS
+	depends on NITRO_ENCLAVES && KUNIT
+	default KUNIT_ALL_TESTS
 	help
 	  Enable KUnit tests for the misc device functionality of the Nitro
 	  Enclaves. Select this option only if you will boot the kernel for

drivers/virt/nitro_enclaves/ne_misc_dev.c

@@ -1759,35 +1759,10 @@ static long ne_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 
 #if defined(CONFIG_NITRO_ENCLAVES_MISC_DEV_TEST)
 #include "ne_misc_dev_test.c"
-
-static inline int ne_misc_dev_test_init(void)
-{
-	return __kunit_test_suites_init(ne_misc_dev_test_suites);
-}
-
-static inline void ne_misc_dev_test_exit(void)
-{
-	__kunit_test_suites_exit(ne_misc_dev_test_suites);
-}
-#else
-static inline int ne_misc_dev_test_init(void)
-{
-	return 0;
-}
-
-static inline void ne_misc_dev_test_exit(void)
-{
-}
 #endif
 
 static int __init ne_init(void)
 {
-	int rc = 0;
-
-	rc = ne_misc_dev_test_init();
-	if (rc < 0)
-		return rc;
-
 	mutex_init(&ne_cpu_pool.mutex);
 
 	return pci_register_driver(&ne_pci_driver);
@@ -1798,8 +1773,6 @@ static void __exit ne_exit(void)
 	pci_unregister_driver(&ne_pci_driver);
 
 	ne_teardown_cpu_pool();
-
-	ne_misc_dev_test_exit();
 }
 
 module_init(ne_init);

drivers/virt/nitro_enclaves/ne_misc_dev_test.c

@@ -151,7 +151,4 @@ static struct kunit_suite ne_misc_dev_test_suite = {
 	.test_cases = ne_misc_dev_test_cases,
 };
 
-static struct kunit_suite *ne_misc_dev_test_suites[] = {
-	&ne_misc_dev_test_suite,
-	NULL
-};
+kunit_test_suite(ne_misc_dev_test_suite);

include/kunit/test.h

@@ -237,9 +237,9 @@ size_t kunit_suite_num_test_cases(struct kunit_suite *suite);
 unsigned int kunit_test_case_num(struct kunit_suite *suite,
 				 struct kunit_case *test_case);
 
-int __kunit_test_suites_init(struct kunit_suite * const * const suites);
+int __kunit_test_suites_init(struct kunit_suite * const * const suites, int num_suites);
 
-void __kunit_test_suites_exit(struct kunit_suite **suites);
+void __kunit_test_suites_exit(struct kunit_suite **suites, int num_suites);
 
 #if IS_BUILTIN(CONFIG_KUNIT)
 int kunit_run_all_tests(void);
@@ -250,43 +250,11 @@ static inline int kunit_run_all_tests(void)
 }
 #endif /* IS_BUILTIN(CONFIG_KUNIT) */
 
-#ifdef MODULE
-/**
- * kunit_test_suites_for_module() - used to register one or more
- *			 &struct kunit_suite with KUnit.
- *
- * @__suites: a statically allocated list of &struct kunit_suite.
- *
- * Registers @__suites with the test framework. See &struct kunit_suite for
- * more information.
- *
- * If a test suite is built-in, module_init() gets translated into
- * an initcall which we don't want as the idea is that for builtins
- * the executor will manage execution.  So ensure we do not define
- * module_{init|exit} functions for the builtin case when registering
- * suites via kunit_test_suites() below.
- */
-#define kunit_test_suites_for_module(__suites)				\
-	static int __init kunit_test_suites_init(void)			\
-	{								\
-		return __kunit_test_suites_init(__suites);		\
-	}								\
-	module_init(kunit_test_suites_init);				\
-									\
-	static void __exit kunit_test_suites_exit(void)			\
-	{								\
-		return __kunit_test_suites_exit(__suites);		\
-	}								\
-	module_exit(kunit_test_suites_exit)
-#else
-#define kunit_test_suites_for_module(__suites)
-#endif /* MODULE */
-
-#define __kunit_test_suites(unique_array, unique_suites, ...)		       \
-	static struct kunit_suite *unique_array[] = { __VA_ARGS__, NULL };     \
-	kunit_test_suites_for_module(unique_array);			       \
-	static struct kunit_suite **unique_suites			       \
-	__used __section(".kunit_test_suites") = unique_array
+#define __kunit_test_suites(unique_array, ...)				       \
+	MODULE_INFO(test, "Y");						       \
+	static struct kunit_suite *unique_array[]			       \
+	__aligned(sizeof(struct kunit_suite *))				       \
+	__used __section(".kunit_test_suites") = { __VA_ARGS__ }
 
 /**
  * kunit_test_suites() - used to register one or more &struct kunit_suite
@@ -294,21 +262,16 @@ static inline int kunit_run_all_tests(void)
  *
  * @__suites: a statically allocated list of &struct kunit_suite.
  *
- * Registers @suites with the test framework. See &struct kunit_suite for
- * more information.
- *
- * When builtin,  KUnit tests are all run via executor; this is done
- * by placing the array of struct kunit_suite * in the .kunit_test_suites
- * ELF section.
+ * Registers @suites with the test framework.
+ * This is done by placing the array of struct kunit_suite * in the
+ * .kunit_test_suites ELF section.
  *
- * An alternative is to build the tests as a module.  Because modules do not
- * support multiple initcall()s, we need to initialize an array of suites for a
- * module.
+ * When builtin, KUnit tests are all run via the executor at boot, and when
+ * built as a module, they run on module load.
  *
  */
 #define kunit_test_suites(__suites...)						\
 	__kunit_test_suites(__UNIQUE_ID(array),				\
-			    __UNIQUE_ID(suites),			\
 			    ##__suites)
 
 #define kunit_test_suite(suite)	kunit_test_suites(&suite)
@@ -320,7 +283,7 @@ static inline int kunit_run_all_tests(void)
  *
  * @__suites: a statically allocated list of &struct kunit_suite.
  *
- * This functions identically as &kunit_test_suites() except that it suppresses
+ * This functions identically as kunit_test_suites() except that it suppresses
  * modpost warnings for referencing functions marked __init or data marked
  * __initdata; this is OK because currently KUnit only runs tests upon boot
  * during the init phase or upon loading a module during the init phase.

include/linux/module.h

@@ -505,6 +505,11 @@ struct module {
 	int num_static_call_sites;
 	struct static_call_site *static_call_sites;
 #endif
+#if IS_ENABLED(CONFIG_KUNIT)
+	int num_kunit_suites;
+	struct kunit_suite **kunit_suites;
+#endif
+
 
 #ifdef CONFIG_LIVEPATCH
 	bool klp; /* Is this a livepatch module? */

include/linux/panic.h

@@ -68,7 +68,8 @@ static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout)
 #define TAINT_LIVEPATCH			15
 #define TAINT_AUX			16
 #define TAINT_RANDSTRUCT		17
-#define TAINT_FLAGS_COUNT		18
+#define TAINT_TEST			18
+#define TAINT_FLAGS_COUNT		19
 #define TAINT_FLAGS_MAX			((1UL << TAINT_FLAGS_COUNT) - 1)
 
 struct taint_flag {

kernel/kcsan/.kunitconfig

+# Note that the KCSAN tests need to run on an SMP setup.
+# Under kunit_tool, this can be done by using the --qemu_args
+# option to configure a machine with several cores. For example:
+# ./tools/testing/kunit/kunit.py run --kunitconfig=kernel/kcsan \
+# 				 --arch=x86_64 --qemu_args="-smp 8"
+
+CONFIG_KUNIT=y
+
+CONFIG_DEBUG_KERNEL=y
+
+# Need some level of concurrency to test a concurrency sanitizer.
+CONFIG_SMP=y
+
+CONFIG_KCSAN=y
+CONFIG_KCSAN_KUNIT_TEST=y
+
+# Set these if you want to run test_barrier_nothreads
+#CONFIG_KCSAN_STRICT=y
+#CONFIG_KCSAN_WEAK_MEMORY=y
+
+# This prevents the test from timing out on many setups. Feel free to remove
+# (or alter) this, in conjunction with setting a different test timeout with,
+# for example, the --timeout kunit_tool option.
+CONFIG_KCSAN_REPORT_ONCE_IN_MS=100

kernel/module/main.c

@@ -1988,6 +1988,13 @@ static int check_modinfo(struct module *mod, struct load_info *info, int flags)
 	/* Set up license info based on the info section */
 	set_license(mod, get_modinfo(info, "license"));
 
+	if (get_modinfo(info, "test")) {
+		if (!test_taint(TAINT_TEST))
+			pr_warn("%s: loading test module taints kernel.\n",
+				mod->name);
+		add_taint_module(mod, TAINT_TEST, LOCKDEP_STILL_OK);
+	}
+
 	return 0;
 }
 
@@ -2087,6 +2094,12 @@ static int find_module_sections(struct module *mod, struct load_info *info)
 					      sizeof(*mod->static_call_sites),
 					      &mod->num_static_call_sites);
 #endif
+#ifdef CONFIG_KUNIT
+	mod->kunit_suites = section_objs(info, ".kunit_test_suites",
+					      sizeof(*mod->kunit_suites),
+					      &mod->num_kunit_suites);
+#endif
+
 	mod->extable = section_objs(info, "__ex_table",
 				    sizeof(*mod->extable), &mod->num_exentries);
 

kernel/panic.c

@@ -428,6 +428,7 @@ const struct taint_flag taint_flags[TAINT_FLAGS_COUNT] = {
 	[ TAINT_LIVEPATCH ]		= { 'K', ' ', true },
 	[ TAINT_AUX ]			= { 'X', ' ', true },
 	[ TAINT_RANDSTRUCT ]		= { 'T', ' ', true },
+	[ TAINT_TEST ]			= { 'N', ' ', true },
 };
 
 /**

lib/kunit/executor.c

@@ -9,8 +9,8 @@
  * These symbols point to the .kunit_test_suites section and are defined in
  * include/asm-generic/vmlinux.lds.h, and consequently must be extern.
  */
-extern struct kunit_suite * const * const __kunit_suites_start[];
-extern struct kunit_suite * const * const __kunit_suites_end[];
+extern struct kunit_suite * const __kunit_suites_start[];
+extern struct kunit_suite * const __kunit_suites_end[];
 
 #if IS_BUILTIN(CONFIG_KUNIT)
 
@@ -55,7 +55,7 @@ static void kunit_parse_filter_glob(struct kunit_test_filter *parsed,
 
 /* Create a copy of suite with only tests that match test_glob. */
 static struct kunit_suite *
-kunit_filter_tests(struct kunit_suite *const suite, const char *test_glob)
+kunit_filter_tests(const struct kunit_suite *const suite, const char *test_glob)
 {
 	int n = 0;
 	struct kunit_case *filtered, *test_case;
@@ -69,15 +69,15 @@ kunit_filter_tests(struct kunit_suite *const suite, const char *test_glob)
 	if (n == 0)
 		return NULL;
 
-	/* Use memcpy to workaround copy->name being const. */
-	copy = kmalloc(sizeof(*copy), GFP_KERNEL);
+	copy = kmemdup(suite, sizeof(*copy), GFP_KERNEL);
 	if (!copy)
 		return ERR_PTR(-ENOMEM);
-	memcpy(copy, suite, sizeof(*copy));
 
 	filtered = kcalloc(n + 1, sizeof(*filtered), GFP_KERNEL);
-	if (!filtered)
+	if (!filtered) {
+		kfree(copy);
 		return ERR_PTR(-ENOMEM);
+	}
 
 	n = 0;
 	kunit_suite_for_each_test_case(suite, test_case) {
@@ -92,62 +92,18 @@ kunit_filter_tests(struct kunit_suite *const suite, const char *test_glob)
 static char *kunit_shutdown;
 core_param(kunit_shutdown, kunit_shutdown, charp, 0644);
 
-static struct kunit_suite * const *
-kunit_filter_subsuite(struct kunit_suite * const * const subsuite,
-		      struct kunit_test_filter *filter)
-{
-	int i, n = 0;
-	struct kunit_suite **filtered, *filtered_suite;
-
-	n = 0;
-	for (i = 0; subsuite[i]; ++i) {
-		if (glob_match(filter->suite_glob, subsuite[i]->name))
-			++n;
-	}
-
-	if (n == 0)
-		return NULL;
-
-	filtered = kmalloc_array(n + 1, sizeof(*filtered), GFP_KERNEL);
-	if (!filtered)
-		return ERR_PTR(-ENOMEM);
-
-	n = 0;
-	for (i = 0; subsuite[i] != NULL; ++i) {
-		if (!glob_match(filter->suite_glob, subsuite[i]->name))
-			continue;
-		filtered_suite = kunit_filter_tests(subsuite[i], filter->test_glob);
-		if (IS_ERR(filtered_suite))
-			return ERR_CAST(filtered_suite);
-		else if (filtered_suite)
-			filtered[n++] = filtered_suite;
-	}
-	filtered[n] = NULL;
-
-	return filtered;
-}
-
+/* Stores an array of suites, end points one past the end */
 struct suite_set {
-	struct kunit_suite * const * const *start;
-	struct kunit_suite * const * const *end;
+	struct kunit_suite * const *start;
+	struct kunit_suite * const *end;
 };
 
-static void kunit_free_subsuite(struct kunit_suite * const *subsuite)
-{
-	unsigned int i;
-
-	for (i = 0; subsuite[i]; i++)
-		kfree(subsuite[i]);
-
-	kfree(subsuite);
-}
-
 static void kunit_free_suite_set(struct suite_set suite_set)
 {
-	struct kunit_suite * const * const *suites;
+	struct kunit_suite * const *suites;
 
 	for (suites = suite_set.start; suites < suite_set.end; suites++)
-		kunit_free_subsuite(*suites);
+		kfree(*suites);
 	kfree(suite_set.start);
 }
 
@@ -156,7 +112,7 @@ static struct suite_set kunit_filter_suites(const struct suite_set *suite_set,
 					    int *err)
 {
 	int i;
-	struct kunit_suite * const **copy, * const *filtered_subsuite;
+	struct kunit_suite **copy, *filtered_suite;
 	struct suite_set filtered;
 	struct kunit_test_filter filter;
 
@@ -171,14 +127,19 @@ static struct suite_set kunit_filter_suites(const struct suite_set *suite_set,
 
 	kunit_parse_filter_glob(&filter, filter_glob);
 
-	for (i = 0; i < max; ++i) {
-		filtered_subsuite = kunit_filter_subsuite(suite_set->start[i], &filter);
-		if (IS_ERR(filtered_subsuite)) {
-			*err = PTR_ERR(filtered_subsuite);
+	for (i = 0; &suite_set->start[i] != suite_set->end; i++) {
+		if (!glob_match(filter.suite_glob, suite_set->start[i]->name))
+			continue;
+
+		filtered_suite = kunit_filter_tests(suite_set->start[i], filter.test_glob);
+		if (IS_ERR(filtered_suite)) {
+			*err = PTR_ERR(filtered_suite);
 			return filtered;
 		}
-		if (filtered_subsuite)
-			*copy++ = filtered_subsuite;
+		if (!filtered_suite)
+			continue;
+
+		*copy++ = filtered_suite;
 	}
 	filtered.end = copy;
 
@@ -201,52 +162,33 @@ static void kunit_handle_shutdown(void)
 
 }
 
-static void kunit_print_tap_header(struct suite_set *suite_set)
-{
-	struct kunit_suite * const * const *suites, * const *subsuite;
-	int num_of_suites = 0;
-
-	for (suites = suite_set->start; suites < suite_set->end; suites++)
-		for (subsuite = *suites; *subsuite != NULL; subsuite++)
-			num_of_suites++;
-
-	pr_info("TAP version 14\n");
-	pr_info("1..%d\n", num_of_suites);
-}
-
 static void kunit_exec_run_tests(struct suite_set *suite_set)
 {
-	struct kunit_suite * const * const *suites;
+	size_t num_suites = suite_set->end - suite_set->start;
 
-	kunit_print_tap_header(suite_set);
+	pr_info("TAP version 14\n");
+	pr_info("1..%zu\n", num_suites);
 
-	for (suites = suite_set->start; suites < suite_set->end; suites++)
-		__kunit_test_suites_init(*suites);
+	__kunit_test_suites_init(suite_set->start, num_suites);
 }
 
 static void kunit_exec_list_tests(struct suite_set *suite_set)
 {
-	unsigned int i;
-	struct kunit_suite * const * const *suites;
+	struct kunit_suite * const *suites;
 	struct kunit_case *test_case;
 
 	/* Hack: print a tap header so kunit.py can find the start of KUnit output. */
 	pr_info("TAP version 14\n");
 
 	for (suites = suite_set->start; suites < suite_set->end; suites++)
-		for (i = 0; (*suites)[i] != NULL; i++) {
-			kunit_suite_for_each_test_case((*suites)[i], test_case) {
-				pr_info("%s.%s\n", (*suites)[i]->name, test_case->name);
-			}
+		kunit_suite_for_each_test_case((*suites), test_case) {
+			pr_info("%s.%s\n", (*suites)->name, test_case->name);
 		}
 }
 
 int kunit_run_all_tests(void)
 {
-	struct suite_set suite_set = {
-		.start = __kunit_suites_start,
-		.end = __kunit_suites_end,
-	};
+	struct suite_set suite_set = {__kunit_suites_start, __kunit_suites_end};
 	int err = 0;
 
 	if (filter_glob_param) {
@@ -264,11 +206,10 @@ int kunit_run_all_tests(void)
 	else
 		pr_err("kunit executor: unknown action '%s'\n", action_param);
 
-	if (filter_glob_param) { /* a copy was made of each array */
+	if (filter_glob_param) { /* a copy was made of each suite */
 		kunit_free_suite_set(suite_set);
 	}
 
-
 out:
 	kunit_handle_shutdown();
 	return err;

lib/kunit/executor_test.c

@@ -9,8 +9,6 @@
 #include <kunit/test.h>
 
 static void kfree_at_end(struct kunit *test, const void *to_free);
-static void free_subsuite_at_end(struct kunit *test,
-				 struct kunit_suite *const *to_free);
 static struct kunit_suite *alloc_fake_suite(struct kunit *test,
 					    const char *suite_name,
 					    struct kunit_case *test_cases);
@@ -41,126 +39,80 @@ static void parse_filter_test(struct kunit *test)
 	kfree(filter.test_glob);
 }
 
-static void filter_subsuite_test(struct kunit *test)
+static void filter_suites_test(struct kunit *test)
 {
-	struct kunit_suite *subsuite[3] = {NULL, NULL, NULL};
-	struct kunit_suite * const *filtered;
-	struct kunit_test_filter filter = {
-		.suite_glob = "suite2",
-		.test_glob = NULL,
-	};
+	struct kunit_suite *subsuite[3] = {NULL, NULL};
+	struct suite_set suite_set = {.start = subsuite, .end = &subsuite[2]};
+	struct suite_set got;
+	int err = 0;
 
 	subsuite[0] = alloc_fake_suite(test, "suite1", dummy_test_cases);
 	subsuite[1] = alloc_fake_suite(test, "suite2", dummy_test_cases);
 
 	/* Want: suite1, suite2, NULL -> suite2, NULL */
-	filtered = kunit_filter_subsuite(subsuite, &filter);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filtered);
-	free_subsuite_at_end(test, filtered);
+	got = kunit_filter_suites(&suite_set, "suite2", &err);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, got.start);
+	KUNIT_ASSERT_EQ(test, err, 0);
+	kfree_at_end(test, got.start);
 
 	/* Validate we just have suite2 */
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filtered[0]);
-	KUNIT_EXPECT_STREQ(test, (const char *)filtered[0]->name, "suite2");
-	KUNIT_EXPECT_FALSE(test, filtered[1]);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, got.start[0]);
+	KUNIT_EXPECT_STREQ(test, (const char *)got.start[0]->name, "suite2");
+
+	/* Contains one element (end is 1 past end) */
+	KUNIT_ASSERT_EQ(test, got.end - got.start, 1);
 }
 
-static void filter_subsuite_test_glob_test(struct kunit *test)
+static void filter_suites_test_glob_test(struct kunit *test)
 {
-	struct kunit_suite *subsuite[3] = {NULL, NULL, NULL};
-	struct kunit_suite * const *filtered;
-	struct kunit_test_filter filter = {
-		.suite_glob = "suite2",
-		.test_glob = "test2",
-	};
+	struct kunit_suite *subsuite[3] = {NULL, NULL};
+	struct suite_set suite_set = {.start = subsuite, .end = &subsuite[2]};
+	struct suite_set got;
+	int err = 0;
 
 	subsuite[0] = alloc_fake_suite(test, "suite1", dummy_test_cases);
 	subsuite[1] = alloc_fake_suite(test, "suite2", dummy_test_cases);
 
 	/* Want: suite1, suite2, NULL -> suite2 (just test1), NULL */
-	filtered = kunit_filter_subsuite(subsuite, &filter);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filtered);
-	free_subsuite_at_end(test, filtered);
+	got = kunit_filter_suites(&suite_set, "suite2.test2", &err);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, got.start);
+	KUNIT_ASSERT_EQ(test, err, 0);
+	kfree_at_end(test, got.start);
 
 	/* Validate we just have suite2 */
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filtered[0]);
-	KUNIT_EXPECT_STREQ(test, (const char *)filtered[0]->name, "suite2");
-	KUNIT_EXPECT_FALSE(test, filtered[1]);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, got.start[0]);
+	KUNIT_EXPECT_STREQ(test, (const char *)got.start[0]->name, "suite2");
+	KUNIT_ASSERT_EQ(test, got.end - got.start, 1);
 
 	/* Now validate we just have test2 */
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filtered[0]->test_cases);
-	KUNIT_EXPECT_STREQ(test, (const char *)filtered[0]->test_cases[0].name, "test2");
-	KUNIT_EXPECT_FALSE(test, filtered[0]->test_cases[1].name);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, got.start[0]->test_cases);
+	KUNIT_EXPECT_STREQ(test, (const char *)got.start[0]->test_cases[0].name, "test2");
+	KUNIT_EXPECT_FALSE(test, got.start[0]->test_cases[1].name);
 }
 
-static void filter_subsuite_to_empty_test(struct kunit *test)
+static void filter_suites_to_empty_test(struct kunit *test)
 {
-	struct kunit_suite *subsuite[3] = {NULL, NULL, NULL};
-	struct kunit_suite * const *filtered;
-	struct kunit_test_filter filter = {
-		.suite_glob = "not_found",
-		.test_glob = NULL,
-	};
+	struct kunit_suite *subsuite[3] = {NULL, NULL};
+	struct suite_set suite_set = {.start = subsuite, .end = &subsuite[2]};
+	struct suite_set got;
+	int err = 0;
 
 	subsuite[0] = alloc_fake_suite(test, "suite1", dummy_test_cases);
 	subsuite[1] = alloc_fake_suite(test, "suite2", dummy_test_cases);
 
-	filtered = kunit_filter_subsuite(subsuite, &filter);
-	free_subsuite_at_end(test, filtered); /* just in case */
+	got = kunit_filter_suites(&suite_set, "not_found", &err);
+	KUNIT_ASSERT_EQ(test, err, 0);
+	kfree_at_end(test, got.start); /* just in case */
 
-	KUNIT_EXPECT_FALSE_MSG(test, filtered,
-			       "should be NULL to indicate no match");
-}
-
-static void kfree_subsuites_at_end(struct kunit *test, struct suite_set *suite_set)
-{
-	struct kunit_suite * const * const *suites;
-
-	kfree_at_end(test, suite_set->start);
-	for (suites = suite_set->start; suites < suite_set->end; suites++)
-		free_subsuite_at_end(test, *suites);
-}
-
-static void filter_suites_test(struct kunit *test)
-{
-	/* Suites per-file are stored as a NULL terminated array */
-	struct kunit_suite *subsuites[2][2] = {
-		{NULL, NULL},
-		{NULL, NULL},
-	};
-	/* Match the memory layout of suite_set */
-	struct kunit_suite * const * const suites[2] = {
-		subsuites[0], subsuites[1],
-	};
-
-	const struct suite_set suite_set = {
-		.start = suites,
-		.end = suites + 2,
-	};
-	struct suite_set filtered = {.start = NULL, .end = NULL};
-	int err = 0;
-
-	/* Emulate two files, each having one suite */
-	subsuites[0][0] = alloc_fake_suite(test, "suite0", dummy_test_cases);
-	subsuites[1][0] = alloc_fake_suite(test, "suite1", dummy_test_cases);
-
-	/* Filter out suite1 */
-	filtered = kunit_filter_suites(&suite_set, "suite0", &err);
-	kfree_subsuites_at_end(test, &filtered); /* let us use ASSERTs without leaking */
-	KUNIT_EXPECT_EQ(test, err, 0);
-	KUNIT_ASSERT_EQ(test, filtered.end - filtered.start, (ptrdiff_t)1);
-
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filtered.start);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filtered.start[0]);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filtered.start[0][0]);
-	KUNIT_EXPECT_STREQ(test, (const char *)filtered.start[0][0]->name, "suite0");
+	KUNIT_EXPECT_PTR_EQ_MSG(test, got.start, got.end,
+				"should be empty to indicate no match");
 }
 
 static struct kunit_case executor_test_cases[] = {
 	KUNIT_CASE(parse_filter_test),
-	KUNIT_CASE(filter_subsuite_test),
-	KUNIT_CASE(filter_subsuite_test_glob_test),
-	KUNIT_CASE(filter_subsuite_to_empty_test),
 	KUNIT_CASE(filter_suites_test),
+	KUNIT_CASE(filter_suites_test_glob_test),
+	KUNIT_CASE(filter_suites_to_empty_test),
 	{}
 };
 
@@ -190,20 +142,6 @@ static void kfree_at_end(struct kunit *test, const void *to_free)
 			     (void *)to_free);
 }
 
-static void free_subsuite_res_free(struct kunit_resource *res)
-{
-	kunit_free_subsuite(res->data);
-}
-
-static void free_subsuite_at_end(struct kunit *test,
-				 struct kunit_suite *const *to_free)
-{
-	if (IS_ERR_OR_NULL(to_free))
-		return;
-	kunit_alloc_resource(test, NULL, free_subsuite_res_free,
-			     GFP_KERNEL, (void *)to_free);
-}
-
 static struct kunit_suite *alloc_fake_suite(struct kunit *test,
 					    const char *suite_name,
 					    struct kunit_case *test_cases)

lib/kunit/test.c

@@ -10,7 +10,9 @@
 #include <kunit/test.h>
 #include <kunit/test-bug.h>
 #include <linux/kernel.h>
+#include <linux/module.h>
 #include <linux/moduleparam.h>
+#include <linux/panic.h>
 #include <linux/sched/debug.h>
 #include <linux/sched.h>
 
@@ -501,6 +503,9 @@ int kunit_run_tests(struct kunit_suite *suite)
 	struct kunit_result_stats suite_stats = { 0 };
 	struct kunit_result_stats total_stats = { 0 };
 
+	/* Taint the kernel so we know we've run tests. */
+	add_taint(TAINT_TEST, LOCKDEP_STILL_OK);
+
 	if (suite->suite_init) {
 		suite->suite_init_err = suite->suite_init(suite);
 		if (suite->suite_init_err) {
@@ -581,11 +586,11 @@ static void kunit_init_suite(struct kunit_suite *suite)
 	suite->suite_init_err = 0;
 }
 
-int __kunit_test_suites_init(struct kunit_suite * const * const suites)
+int __kunit_test_suites_init(struct kunit_suite * const * const suites, int num_suites)
 {
 	unsigned int i;
 
-	for (i = 0; suites[i] != NULL; i++) {
+	for (i = 0; i < num_suites; i++) {
 		kunit_init_suite(suites[i]);
 		kunit_run_tests(suites[i]);
 	}
@@ -598,17 +603,54 @@ static void kunit_exit_suite(struct kunit_suite *suite)
 	kunit_debugfs_destroy_suite(suite);
 }
 
-void __kunit_test_suites_exit(struct kunit_suite **suites)
+void __kunit_test_suites_exit(struct kunit_suite **suites, int num_suites)
 {
 	unsigned int i;
 
-	for (i = 0; suites[i] != NULL; i++)
+	for (i = 0; i < num_suites; i++)
 		kunit_exit_suite(suites[i]);
 
 	kunit_suite_counter = 1;
 }
 EXPORT_SYMBOL_GPL(__kunit_test_suites_exit);
 
+#ifdef CONFIG_MODULES
+static void kunit_module_init(struct module *mod)
+{
+	__kunit_test_suites_init(mod->kunit_suites, mod->num_kunit_suites);
+}
+
+static void kunit_module_exit(struct module *mod)
+{
+	__kunit_test_suites_exit(mod->kunit_suites, mod->num_kunit_suites);
+}
+
+static int kunit_module_notify(struct notifier_block *nb, unsigned long val,
+			       void *data)
+{
+	struct module *mod = data;
+
+	switch (val) {
+	case MODULE_STATE_LIVE:
+		kunit_module_init(mod);
+		break;
+	case MODULE_STATE_GOING:
+		kunit_module_exit(mod);
+		break;
+	case MODULE_STATE_COMING:
+	case MODULE_STATE_UNFORMED:
+		break;
+	}
+
+	return 0;
+}
+
+static struct notifier_block kunit_mod_nb = {
+	.notifier_call = kunit_module_notify,
+	.priority = 0,
+};
+#endif
+
 struct kunit_kmalloc_array_params {
 	size_t n;
 	size_t size;
@@ -703,13 +745,19 @@ EXPORT_SYMBOL_GPL(kunit_cleanup);
 static int __init kunit_init(void)
 {
 	kunit_debugfs_init();
-
+#ifdef CONFIG_MODULES
+	return register_module_notifier(&kunit_mod_nb);
+#else
 	return 0;
+#endif
 }
 late_initcall(kunit_init);
 
 static void __exit kunit_exit(void)
 {
+#ifdef CONFIG_MODULES
+	unregister_module_notifier(&kunit_mod_nb);
+#endif
 	kunit_debugfs_cleanup();
 }
 module_exit(kunit_exit);

scripts/mod/modpost.c

@@ -2191,6 +2191,9 @@ static void add_header(struct buffer *b, struct module *mod)
 
 	if (strstarts(mod->name, "drivers/staging"))
 		buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
+
+	if (strstarts(mod->name, "tools/testing"))
+		buf_printf(b, "\nMODULE_INFO(test, \"Y\");\n");
 }
 
 static void add_exported_symbols(struct buffer *buf, struct module *mod)

security/apparmor/policy_unpack_test.c

@@ -177,7 +177,7 @@ static void policy_unpack_test_unpack_array_out_of_bounds(struct kunit *test)
 
 	array_size = unpack_array(puf->e, name);
 
-	KUNIT_EXPECT_EQ(test, array_size, (u16)0);
+	KUNIT_EXPECT_EQ(test, array_size, 0);
 	KUNIT_EXPECT_PTR_EQ(test, puf->e->pos,
 		puf->e->start + TEST_NAMED_ARRAY_BUF_OFFSET);
 }
@@ -391,10 +391,10 @@ static void policy_unpack_test_unpack_u16_chunk_basic(struct kunit *test)
 
 	size = unpack_u16_chunk(puf->e, &chunk);
 
-	KUNIT_EXPECT_PTR_EQ(test, (void *)chunk,
+	KUNIT_EXPECT_PTR_EQ(test, chunk,
 			    puf->e->start + TEST_U16_OFFSET + 2);
-	KUNIT_EXPECT_EQ(test, size, (size_t)TEST_U16_DATA);
-	KUNIT_EXPECT_PTR_EQ(test, puf->e->pos, (void *)(chunk + TEST_U16_DATA));
+	KUNIT_EXPECT_EQ(test, size, TEST_U16_DATA);
+	KUNIT_EXPECT_PTR_EQ(test, puf->e->pos, (chunk + TEST_U16_DATA));
 }
 
 static void policy_unpack_test_unpack_u16_chunk_out_of_bounds_1(
@@ -408,7 +408,7 @@ static void policy_unpack_test_unpack_u16_chunk_out_of_bounds_1(
 
 	size = unpack_u16_chunk(puf->e, &chunk);
 
-	KUNIT_EXPECT_EQ(test, size, (size_t)0);
+	KUNIT_EXPECT_EQ(test, size, 0);
 	KUNIT_EXPECT_NULL(test, chunk);
 	KUNIT_EXPECT_PTR_EQ(test, puf->e->pos, puf->e->end - 1);
 }
@@ -430,7 +430,7 @@ static void policy_unpack_test_unpack_u16_chunk_out_of_bounds_2(
 
 	size = unpack_u16_chunk(puf->e, &chunk);
 
-	KUNIT_EXPECT_EQ(test, size, (size_t)0);
+	KUNIT_EXPECT_EQ(test, size, 0);
 	KUNIT_EXPECT_NULL(test, chunk);
 	KUNIT_EXPECT_PTR_EQ(test, puf->e->pos, puf->e->start + TEST_U16_OFFSET);
 }

tools/testing/kunit/configs/arch_uml.config

+# Config options which are added to UML builds by default
+
+# Enable virtio/pci, as a lot of tests require it.
+CONFIG_VIRTIO_UML=y
+CONFIG_UML_PCI_OVER_VIRTIO=y

tools/testing/kunit/configs/coverage_uml.config

+# This config fragment enables coverage on UML, which is different from the
+# normal gcov used in other arches (no debugfs).
+# Example usage:
+# ./tools/testing/kunit/kunit.py run \
+#   --kunitconfig=tools/testing/kunit/configs/all_tests_uml.config \
+#   --kunitconfig=tools/testing/kunit/configs/coverage_uml.config
+
+CONFIG_DEBUG_KERNEL=y
+CONFIG_DEBUG_INFO=y
+CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y
+CONFIG_GCOV=y

tools/testing/kunit/kunit.py

@@ -10,6 +10,7 @@
 import argparse
 import os
 import re
+import shlex
 import sys
 import time
 
@@ -22,6 +23,7 @@ from typing import Iterable, List, Optional, Sequence, Tuple
 import kunit_json
 import kunit_kernel
 import kunit_parser
+from kunit_printer import stdout
 
 class KunitStatus(Enum):
 	SUCCESS = auto()
@@ -72,7 +74,7 @@ def get_kernel_root_path() -> str:
 
 def config_tests(linux: kunit_kernel.LinuxSourceTree,
 		 request: KunitConfigRequest) -> KunitResult:
-	kunit_parser.print_with_timestamp('Configuring KUnit Kernel ...')
+	stdout.print_with_timestamp('Configuring KUnit Kernel ...')
 
 	config_start = time.time()
 	success = linux.build_reconfig(request.build_dir, request.make_options)
@@ -85,7 +87,7 @@ def config_tests(linux: kunit_kernel.LinuxSourceTree,
 
 def build_tests(linux: kunit_kernel.LinuxSourceTree,
 		request: KunitBuildRequest) -> KunitResult:
-	kunit_parser.print_with_timestamp('Building KUnit Kernel ...')
+	stdout.print_with_timestamp('Building KUnit Kernel ...')
 
 	build_start = time.time()
 	success = linux.build_kernel(request.alltests,
@@ -158,7 +160,7 @@ def exec_tests(linux: kunit_kernel.LinuxSourceTree, request: KunitExecRequest) -
 	test_counts = kunit_parser.TestCounts()
 	exec_time = 0.0
 	for i, filter_glob in enumerate(filter_globs):
-		kunit_parser.print_with_timestamp('Starting KUnit Kernel ({}/{})...'.format(i+1, len(filter_globs)))
+		stdout.print_with_timestamp('Starting KUnit Kernel ({}/{})...'.format(i+1, len(filter_globs)))
 
 		test_start = time.time()
 		run_result = linux.run_kernel(
@@ -221,7 +223,7 @@ def parse_tests(request: KunitParseRequest, metadata: kunit_json.Metadata, input
 		else:
 			with open(request.json, 'w') as f:
 				f.write(json_str)
-			kunit_parser.print_with_timestamp("Test results stored in %s" %
+			stdout.print_with_timestamp("Test results stored in %s" %
 				os.path.abspath(request.json))
 
 	if test_result.status != kunit_parser.TestStatus.SUCCESS:
@@ -245,7 +247,7 @@ def run_tests(linux: kunit_kernel.LinuxSourceTree,
 
 	run_end = time.time()
 
-	kunit_parser.print_with_timestamp((
+	stdout.print_with_timestamp((
 		'Elapsed time: %.3fs total, %.3fs configuring, %.3fs ' +
 		'building, %.3fs running\n') % (
 				run_end - run_start,
@@ -291,8 +293,9 @@ def add_common_opts(parser) -> None:
 	parser.add_argument('--kunitconfig',
 			     help='Path to Kconfig fragment that enables KUnit tests.'
 			     ' If given a directory, (e.g. lib/kunit), "/.kunitconfig" '
-			     'will get  automatically appended.',
-			     metavar='PATH')
+			     'will get  automatically appended. If repeated, the files '
+			     'blindly concatenated, which might not work in all cases.',
+			     action='append', metavar='PATHS')
 	parser.add_argument('--kconfig_add',
 			     help='Additional Kconfig options to append to the '
 			     '.kunitconfig, e.g. CONFIG_KASAN=y. Can be repeated.',
@@ -323,6 +326,10 @@ def add_common_opts(parser) -> None:
 				  'a QemuArchParams object.'),
 			    type=str, metavar='FILE')
 
+	parser.add_argument('--qemu_args',
+			    help='Additional QEMU arguments, e.g. "-smp 8"',
+			    action='append', metavar='')
+
 def add_build_opts(parser) -> None:
 	parser.add_argument('--jobs',
 			    help='As in the make command, "Specifies  the number of '
@@ -365,7 +372,25 @@ def add_parse_opts(parser) -> None:
 			    'filename is specified',
 			    type=str, const='stdout', default=None, metavar='FILE')
 
-def main(argv, linux=None):
+
+def tree_from_args(cli_args: argparse.Namespace) -> kunit_kernel.LinuxSourceTree:
+	"""Returns a LinuxSourceTree based on the user's arguments."""
+	# Allow users to specify multiple arguments in one string, e.g. '-smp 8'
+	qemu_args: List[str] = []
+	if cli_args.qemu_args:
+		for arg in cli_args.qemu_args:
+			qemu_args.extend(shlex.split(arg))
+
+	return kunit_kernel.LinuxSourceTree(cli_args.build_dir,
+			kunitconfig_paths=cli_args.kunitconfig,
+			kconfig_add=cli_args.kconfig_add,
+			arch=cli_args.arch,
+			cross_compile=cli_args.cross_compile,
+			qemu_config_path=cli_args.qemu_config,
+			extra_qemu_args=qemu_args)
+
+
+def main(argv):
 	parser = argparse.ArgumentParser(
 			description='Helps writing and running KUnit tests.')
 	subparser = parser.add_subparsers(dest='subcommand')
@@ -412,14 +437,7 @@ def main(argv, linux=None):
 		if not os.path.exists(cli_args.build_dir):
 			os.mkdir(cli_args.build_dir)
 
-		if not linux:
-			linux = kunit_kernel.LinuxSourceTree(cli_args.build_dir,
-					kunitconfig_path=cli_args.kunitconfig,
-					kconfig_add=cli_args.kconfig_add,
-					arch=cli_args.arch,
-					cross_compile=cli_args.cross_compile,
-					qemu_config_path=cli_args.qemu_config)
-
+		linux = tree_from_args(cli_args)
 		request = KunitRequest(build_dir=cli_args.build_dir,
 				       make_options=cli_args.make_options,
 				       jobs=cli_args.jobs,
@@ -438,50 +456,29 @@ def main(argv, linux=None):
 				not os.path.exists(cli_args.build_dir)):
 			os.mkdir(cli_args.build_dir)
 
-		if not linux:
-			linux = kunit_kernel.LinuxSourceTree(cli_args.build_dir,
-					kunitconfig_path=cli_args.kunitconfig,
-					kconfig_add=cli_args.kconfig_add,
-					arch=cli_args.arch,
-					cross_compile=cli_args.cross_compile,
-					qemu_config_path=cli_args.qemu_config)
-
+		linux = tree_from_args(cli_args)
 		request = KunitConfigRequest(build_dir=cli_args.build_dir,
 					     make_options=cli_args.make_options)
 		result = config_tests(linux, request)
-		kunit_parser.print_with_timestamp((
+		stdout.print_with_timestamp((
 			'Elapsed time: %.3fs\n') % (
 				result.elapsed_time))
 		if result.status != KunitStatus.SUCCESS:
 			sys.exit(1)
 	elif cli_args.subcommand == 'build':
-		if not linux:
-			linux = kunit_kernel.LinuxSourceTree(cli_args.build_dir,
-					kunitconfig_path=cli_args.kunitconfig,
-					kconfig_add=cli_args.kconfig_add,
-					arch=cli_args.arch,
-					cross_compile=cli_args.cross_compile,
-					qemu_config_path=cli_args.qemu_config)
-
+		linux = tree_from_args(cli_args)
 		request = KunitBuildRequest(build_dir=cli_args.build_dir,
 					    make_options=cli_args.make_options,
 					    jobs=cli_args.jobs,
 					    alltests=cli_args.alltests)
 		result = config_and_build_tests(linux, request)
-		kunit_parser.print_with_timestamp((
+		stdout.print_with_timestamp((
 			'Elapsed time: %.3fs\n') % (
 				result.elapsed_time))
 		if result.status != KunitStatus.SUCCESS:
 			sys.exit(1)
 	elif cli_args.subcommand == 'exec':
-		if not linux:
-			linux = kunit_kernel.LinuxSourceTree(cli_args.build_dir,
-					kunitconfig_path=cli_args.kunitconfig,
-					kconfig_add=cli_args.kconfig_add,
-					arch=cli_args.arch,
-					cross_compile=cli_args.cross_compile,
-					qemu_config_path=cli_args.qemu_config)
-
+		linux = tree_from_args(cli_args)
 		exec_request = KunitExecRequest(raw_output=cli_args.raw_output,
 						build_dir=cli_args.build_dir,
 						json=cli_args.json,
@@ -491,7 +488,7 @@ def main(argv, linux=None):
 						kernel_args=cli_args.kernel_args,
 						run_isolated=cli_args.run_isolated)
 		result = exec_tests(linux, exec_request)
-		kunit_parser.print_with_timestamp((
+		stdout.print_with_timestamp((
 			'Elapsed time: %.3fs\n') % (result.elapsed_time))
 		if result.status != KunitStatus.SUCCESS:
 			sys.exit(1)

tools/testing/kunit/kunit_config.py

@@ -8,7 +8,7 @@
 
 from dataclasses import dataclass
 import re
-from typing import List, Set
+from typing import Dict, Iterable, List, Set, Tuple
 
 CONFIG_IS_NOT_SET_PATTERN = r'^# CONFIG_(\w+) is not set$'
 CONFIG_PATTERN = r'^CONFIG_(\w+)=(\S+|".*")$'
@@ -32,35 +32,51 @@ class Kconfig:
 	"""Represents defconfig or .config specified using the Kconfig language."""
 
 	def __init__(self) -> None:
-		self._entries = []  # type: List[KconfigEntry]
+		self._entries = {}  # type: Dict[str, str]
 
-	def entries(self) -> Set[KconfigEntry]:
-		return set(self._entries)
+	def __eq__(self, other) -> bool:
+		if not isinstance(other, self.__class__):
+			return False
+		return self._entries == other._entries
 
-	def add_entry(self, entry: KconfigEntry) -> None:
-		self._entries.append(entry)
+	def __repr__(self) -> str:
+		return ','.join(str(e) for e in self.as_entries())
+
+	def as_entries(self) -> Iterable[KconfigEntry]:
+		for name, value in self._entries.items():
+			yield KconfigEntry(name, value)
+
+	def add_entry(self, name: str, value: str) -> None:
+		self._entries[name] = value
 
 	def is_subset_of(self, other: 'Kconfig') -> bool:
-		other_dict = {e.name: e.value for e in other.entries()}
-		for a in self.entries():
-			b = other_dict.get(a.name)
+		for name, value in self._entries.items():
+			b = other._entries.get(name)
 			if b is None:
-				if a.value == 'n':
+				if value == 'n':
 					continue
 				return False
-			if a.value != b:
+			if value != b:
 				return False
 		return True
 
+	def conflicting_options(self, other: 'Kconfig') -> List[Tuple[KconfigEntry, KconfigEntry]]:
+		diff = []  # type: List[Tuple[KconfigEntry, KconfigEntry]]
+		for name, value in self._entries.items():
+			b = other._entries.get(name)
+			if b and value != b:
+				pair = (KconfigEntry(name, value), KconfigEntry(name, b))
+				diff.append(pair)
+		return diff
+
 	def merge_in_entries(self, other: 'Kconfig') -> None:
-		if other.is_subset_of(self):
-			return
-		self._entries = list(self.entries().union(other.entries()))
+		for name, value in other._entries.items():
+			self._entries[name] = value
 
 	def write_to_file(self, path: str) -> None:
 		with open(path, 'a+') as f:
-			for entry in self.entries():
-				f.write(str(entry) + '\n')
+			for e in self.as_entries():
+				f.write(str(e) + '\n')
 
 def parse_file(path: str) -> Kconfig:
 	with open(path, 'r') as f:
@@ -78,14 +94,12 @@ def parse_from_string(blob: str) -> Kconfig:
 
 		match = config_matcher.match(line)
 		if match:
-			entry = KconfigEntry(match.group(1), match.group(2))
-			kconfig.add_entry(entry)
+			kconfig.add_entry(match.group(1), match.group(2))
 			continue
 
 		empty_match = is_not_set_matcher.match(line)
 		if empty_match:
-			entry = KconfigEntry(empty_match.group(1), 'n')
-			kconfig.add_entry(entry)
+			kconfig.add_entry(empty_match.group(1), 'n')
 			continue
 
 		if line[0] == '#':

tools/testing/kunit/kunit_parser.py

@@ -13,10 +13,11 @@ from __future__ import annotations
 import re
 import sys
 
-import datetime
 from enum import Enum, auto
 from typing import Iterable, Iterator, List, Optional, Tuple
 
+from kunit_printer import stdout
+
 class Test:
 	"""
 	A class to represent a test parsed from KTAP results. All KTAP
@@ -55,7 +56,7 @@ class Test:
 	def add_error(self, error_message: str) -> None:
 		"""Records an error that occurred while parsing this test."""
 		self.counts.errors += 1
-		print_with_timestamp(red('[ERROR]') + f' Test: {self.name}: {error_message}')
+		stdout.print_with_timestamp(stdout.red('[ERROR]') + f' Test: {self.name}: {error_message}')
 
 class TestStatus(Enum):
 	"""An enumeration class to represent the status of a test."""
@@ -461,32 +462,6 @@ def parse_diagnostic(lines: LineStream) -> List[str]:
 
 DIVIDER = '=' * 60
 
-RESET = '\033[0;0m'
-
-def red(text: str) -> str:
-	"""Returns inputted string with red color code."""
-	if not sys.stdout.isatty():
-		return text
-	return '\033[1;31m' + text + RESET
-
-def yellow(text: str) -> str:
-	"""Returns inputted string with yellow color code."""
-	if not sys.stdout.isatty():
-		return text
-	return '\033[1;33m' + text + RESET
-
-def green(text: str) -> str:
-	"""Returns inputted string with green color code."""
-	if not sys.stdout.isatty():
-		return text
-	return '\033[1;32m' + text + RESET
-
-ANSI_LEN = len(red(''))
-
-def print_with_timestamp(message: str) -> None:
-	"""Prints message with timestamp at beginning."""
-	print('[%s] %s' % (datetime.datetime.now().strftime('%H:%M:%S'), message))
-
 def format_test_divider(message: str, len_message: int) -> str:
 	"""
 	Returns string with message centered in fixed width divider.
@@ -529,12 +504,12 @@ def print_test_header(test: Test) -> None:
 			message += ' (1 subtest)'
 		else:
 			message += f' ({test.expected_count} subtests)'
-	print_with_timestamp(format_test_divider(message, len(message)))
+	stdout.print_with_timestamp(format_test_divider(message, len(message)))
 
 def print_log(log: Iterable[str]) -> None:
 	"""Prints all strings in saved log for test in yellow."""
 	for m in log:
-		print_with_timestamp(yellow(m))
+		stdout.print_with_timestamp(stdout.yellow(m))
 
 def format_test_result(test: Test) -> str:
 	"""
@@ -551,16 +526,16 @@ def format_test_result(test: Test) -> str:
 	String containing formatted test result
 	"""
 	if test.status == TestStatus.SUCCESS:
-		return green('[PASSED] ') + test.name
+		return stdout.green('[PASSED] ') + test.name
 	if test.status == TestStatus.SKIPPED:
-		return yellow('[SKIPPED] ') + test.name
+		return stdout.yellow('[SKIPPED] ') + test.name
 	if test.status == TestStatus.NO_TESTS:
-		return yellow('[NO TESTS RUN] ') + test.name
+		return stdout.yellow('[NO TESTS RUN] ') + test.name
 	if test.status == TestStatus.TEST_CRASHED:
 		print_log(test.log)
-		return red('[CRASHED] ') + test.name
+		return stdout.red('[CRASHED] ') + test.name
 	print_log(test.log)
-	return red('[FAILED] ') + test.name
+	return stdout.red('[FAILED] ') + test.name
 
 def print_test_result(test: Test) -> None:
 	"""
@@ -572,7 +547,7 @@ def print_test_result(test: Test) -> None:
 	Parameters:
 	test - Test object representing current test being printed
 	"""
-	print_with_timestamp(format_test_result(test))
+	stdout.print_with_timestamp(format_test_result(test))
 
 def print_test_footer(test: Test) -> None:
 	"""
@@ -585,8 +560,8 @@ def print_test_footer(test: Test) -> None:
 	test - Test object representing current test being printed
 	"""
 	message = format_test_result(test)
-	print_with_timestamp(format_test_divider(message,
-		len(message) - ANSI_LEN))
+	stdout.print_with_timestamp(format_test_divider(message,
+		len(message) - stdout.color_len()))
 
 def print_summary_line(test: Test) -> None:
 	"""
@@ -603,12 +578,12 @@ def print_summary_line(test: Test) -> None:
 	test - Test object representing current test being printed
 	"""
 	if test.status == TestStatus.SUCCESS:
-		color = green
+		color = stdout.green
 	elif test.status in (TestStatus.SKIPPED, TestStatus.NO_TESTS):
-		color = yellow
+		color = stdout.yellow
 	else:
-		color = red
-	print_with_timestamp(color(f'Testing complete. {test.counts}'))
+		color = stdout.red
+	stdout.print_with_timestamp(color(f'Testing complete. {test.counts}'))
 
 # Other methods:
 
@@ -762,7 +737,7 @@ def parse_run_tests(kernel_output: Iterable[str]) -> Test:
 	Return:
 	Test - the main test object with all subtests.
 	"""
-	print_with_timestamp(DIVIDER)
+	stdout.print_with_timestamp(DIVIDER)
 	lines = extract_tap_lines(kernel_output)
 	test = Test()
 	if not lines:
@@ -773,6 +748,6 @@ def parse_run_tests(kernel_output: Iterable[str]) -> Test:
 		test = parse_test(lines, 0, [])
 		if test.status != TestStatus.NO_TESTS:
 			test.status = test.counts.get_status()
-	print_with_timestamp(DIVIDER)
+	stdout.print_with_timestamp(DIVIDER)
 	print_summary_line(test)
 	return test

tools/testing/kunit/kunit_printer.py

+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+#
+# Utilities for printing and coloring output.
+#
+# Copyright (C) 2022, Google LLC.
+# Author: Daniel Latypov <dlatypov@google.com>
+
+import datetime
+import sys
+import typing
+
+_RESET = '\033[0;0m'
+
+class Printer:
+	"""Wraps a file object, providing utilities for coloring output, etc."""
+
+	def __init__(self, output: typing.IO):
+		self._output = output
+		self._use_color = output.isatty()
+
+	def print(self, message: str) -> None:
+		print(message, file=self._output)
+
+	def print_with_timestamp(self, message: str) -> None:
+		ts = datetime.datetime.now().strftime('%H:%M:%S')
+		self.print(f'[{ts}] {message}')
+
+	def _color(self, code: str, text: str) -> str:
+		if not self._use_color:
+			return text
+		return code + text + _RESET
+
+	def red(self, text: str) -> str:
+		return self._color('\033[1;31m', text)
+
+	def yellow(self, text: str) -> str:
+		return self._color('\033[1;33m', text)
+
+	def green(self, text: str) -> str:
+		return self._color('\033[1;32m', text)
+
+	def color_len(self) -> int:
+		"""Returns the length of the color escape codes."""
+		return len(self.red(''))
+
+# Provides a default instance that prints to stdout
+stdout = Printer(sys.stdout)

tools/testing/selftests/kselftest_module.h

@@ -3,6 +3,7 @@
 #define __KSELFTEST_MODULE_H
 
 #include <linux/module.h>
+#include <linux/panic.h>
 
 /*
  * Test framework for writing test modules to be loaded by kselftest.
@@ -41,6 +42,7 @@ static inline int kstm_report(unsigned int total_tests, unsigned int failed_test
 static int __init __module##_init(void)			\
 {							\
 	pr_info("loaded.\n");				\
+	add_taint(TAINT_TEST, LOCKDEP_STILL_OK);	\
 	selftest();					\
 	return kstm_report(total_tests, failed_tests, skipped_tests);	\
 }							\
@@ -51,4 +53,6 @@ static void __exit __module##_exit(void)		\
 module_init(__module##_init);				\
 module_exit(__module##_exit)
 
+MODULE_INFO(test, "Y");
+
 #endif	/* __KSELFTEST_MODULE_H */