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
  ...

Author: torvalds

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 <[email protected]>");
    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)
@@ -637,27 +618,14 @@ 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;
 }
 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"