linux/lib/kunit, branch v6.8

kunit: device: Unregister the kunit_bus on shutdown

2024-02-07T00:07:37Z

If KUnit is built as a module, and it's unloaded, the kunit_bus is not unregistered. This causes an error if it's then re-loaded later, as we try to re-register the bus. Unregister the bus and root_device on shutdown, if it looks valid. In addition, be more specific about the value of kunit_bus_device. It is: - a valid struct device* if the kunit_bus initialised correctly. - an ERR_PTR if it failed to initialise. - NULL before initialisation and after shutdown. Fixes: d03c720e03bd ("kunit: Add APIs for managing devices") Signed-off-by: David Gow Reviewed-by: Rae Moar Signed-off-by: Shuah Khan

kunit: run test suites only after module initialization completes

2024-01-22T14:58:54Z

Commit 2810c1e99867 ("kunit: Fix wild-memory-access bug in kunit_free_suite_set()") fixed a wild-memory-access bug that could have happened during the loading phase of test suites built and executed as loadable modules. However, it also introduced a problematic side effect that causes test suites modules to crash when they attempt to register fake devices. When a module is loaded, it traverses the MODULE_STATE_UNFORMED and MODULE_STATE_COMING states before reaching the normal operating state MODULE_STATE_LIVE. Finally, when the module is removed, it moves to MODULE_STATE_GOING before being released. However, if the loading function load_module() fails between complete_formation() and do_init_module(), the module goes directly from MODULE_STATE_COMING to MODULE_STATE_GOING without passing through MODULE_STATE_LIVE. This behavior was causing kunit_module_exit() to be called without having first executed kunit_module_init(). Since kunit_module_exit() is responsible for freeing the memory allocated by kunit_module_init() through kunit_filter_suites(), this behavior was resulting in a wild-memory-access bug. Commit 2810c1e99867 ("kunit: Fix wild-memory-access bug in kunit_free_suite_set()") fixed this issue by running the tests when the module is still in MODULE_STATE_COMING. However, modules in that state are not fully initialized, lacking sysfs kobjects. Therefore, if a test module attempts to register a fake device, it will inevitably crash. This patch proposes a different approach to fix the original wild-memory-access bug while restoring the normal module execution flow by making kunit_module_exit() able to detect if kunit_module_init() has previously initialized the tests suite set. In this way, test modules can once again register fake devices without crashing. This behavior is achieved by checking whether mod->kunit_suites is a virtual or direct mapping address. If it is a virtual address, then kunit_module_init() has allocated the suite_set in kunit_filter_suites() using kmalloc_array(). On the contrary, if mod->kunit_suites is still pointing to the original address that was set when looking up the .kunit_test_suites section of the module, then the loading phase has failed and there's no memory to be freed. v4: - rebased on 6.8 - noted that kunit_filter_suites() must return a virtual address v3: - add a comment to clarify why the start address is checked v2: - add include Fixes: 2810c1e99867 ("kunit: Fix wild-memory-access bug in kunit_free_suite_set()") Reviewed-by: David Gow Tested-by: Rae Moar Tested-by: Richard Fitzgerald Reviewed-by: Javier Martinez Canillas Signed-off-by: Marco Pagani Signed-off-by: Shuah Khan

kunit: device: Fix a NULL vs IS_ERR() check in init()

2024-01-22T14:58:22Z

The root_device_register() function does not return NULL, it returns error pointers. Fix the check to match. Fixes: d03c720e03bd ("kunit: Add APIs for managing devices") Signed-off-by: Dan Carpenter Reviewed-by: Rae Moar Reviewed-by: David Gow Signed-off-by: Shuah Khan

kunit: Fix a NULL vs IS_ERR() bug

2024-01-22T14:58:12Z

The kunit_device_register() function doesn't return NULL, it returns error pointers. Change the KUNIT_ASSERT_NOT_NULL() to check for ERR_OR_NULL(). Fixes: d03c720e03bd ("kunit: Add APIs for managing devices") Signed-off-by: Dan Carpenter Reviewed-by: Rae Moar Reviewed-by: David Gow Signed-off-by: Shuah Khan

kunit: Fix some comments which were mistakenly kerneldoc

2024-01-03T16:10:37Z

The KUnit device helpers are documented with kerneldoc in their header file, but also have short comments over their implementation. These were mistakenly formatted as kerneldoc comments, even though they're not valid kerneldoc. It shouldn't cause any serious problems -- this file isn't included in the docs -- but it could be confusing, and causes warnings. Remove the extra '*' so that these aren't treated as kerneldoc. Fixes: d03c720e03bd ("kunit: Add APIs for managing devices") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202312181920.H4EPAH20-lkp@intel.com/ Signed-off-by: David Gow Reviewed-by: Randy Dunlap Signed-off-by: Shuah Khan

kunit: Add example of kunit_activate_static_stub() with pointer-to-function

2024-01-03T16:07:23Z

Adds a variant of example_static_stub_test() that shows use of a pointer-to-function with kunit_activate_static_stub(). A const pointer to the add_one() function is declared. This pointer-to-function is passed to kunit_activate_static_stub() and kunit_deactivate_static_stub() instead of passing add_one directly. Signed-off-by: Richard Fitzgerald Reviewed-by: David Gow Signed-off-by: Shuah Khan

kunit: Fix NULL-dereference in kunit_init_suite() if suite->log is NULL

2024-01-03T16:06:19Z

suite->log must be checked for NULL before passing it to string_stream_clear(). This was done in kunit_init_test() but was missing from kunit_init_suite(). Signed-off-by: Richard Fitzgerald Fixes: 6d696c4695c5 ("kunit: add ability to run tests after boot using debugfs") Reviewed-by: Rae Moar Acked-by: David Gow Reviewed-by: Muhammad Usama Anjum Signed-off-by: Shuah Khan

kunit: Reset test->priv after each param iteration

2023-12-18T20:39:05Z

If we run parameterized test that uses test->priv to prepare some custom data, then value of test->priv will leak to the next param iteration and may be unexpected. This could be easily seen if we promote example_priv_test to parameterized test as then only first test iteration will be successful: $ ./tools/testing/kunit/kunit.py run \ --kunitconfig ./lib/kunit/.kunitconfig *.example_priv* [ ] Starting KUnit Kernel (1/1)... [ ] ============================================================ [ ] =================== example (1 subtest) ==================== [ ] ==================== example_priv_test ==================== [ ] [PASSED] example value 3 [ ] # example_priv_test: initializing [ ] # example_priv_test: ASSERTION FAILED at lib/kunit/kunit-example-test.c:230 [ ] Expected test->priv == ((void *)0), but [ ] test->priv == 0000000060dfe290 [ ] ((void *)0) == 0000000000000000 [ ] # example_priv_test: cleaning up [ ] [FAILED] example value 2 [ ] # example_priv_test: initializing [ ] # example_priv_test: ASSERTION FAILED at lib/kunit/kunit-example-test.c:230 [ ] Expected test->priv == ((void *)0), but [ ] test->priv == 0000000060dfe290 [ ] ((void *)0) == 0000000000000000 [ ] # example_priv_test: cleaning up [ ] [FAILED] example value 1 [ ] # example_priv_test: initializing [ ] # example_priv_test: ASSERTION FAILED at lib/kunit/kunit-example-test.c:230 [ ] Expected test->priv == ((void *)0), but [ ] test->priv == 0000000060dfe290 [ ] ((void *)0) == 0000000000000000 [ ] # example_priv_test: cleaning up [ ] [FAILED] example value 0 [ ] # example_priv_test: initializing [ ] # example_priv_test: cleaning up [ ] # example_priv_test: pass:1 fail:3 skip:0 total:4 [ ] ================ [FAILED] example_priv_test ================ [ ] # example: initializing suite [ ] # module: kunit_example_test [ ] # example: exiting suite [ ] # Totals: pass:1 fail:3 skip:0 total:4 [ ] ===================== [FAILED] example ===================== Fix that by resetting test->priv after each param iteration, in similar way what we did for the test->status. Signed-off-by: Michal Wajdeczko Cc: David Gow Cc: Rae Moar Reviewed-by: David Gow Signed-off-by: Shuah Khan

kunit: Add example for using test->priv

2023-12-18T20:39:00Z

In a test->priv field the user can store arbitrary data. Add example how to use this feature in the test code. Signed-off-by: Michal Wajdeczko Cc: David Gow Cc: Rae Moar Reviewed-by: David Gow Signed-off-by: Shuah Khan

kunit: Add APIs for managing devices

2023-12-18T20:28:08Z

Tests for drivers often require a struct device to pass to other functions. While it's possible to create these with root_device_register(), or to use something like a platform device, this is both a misuse of those APIs, and can be difficult to clean up after, for example, a failed assertion. Add some KUnit-specific functions for registering and unregistering a struct device: - kunit_device_register() - kunit_device_register_with_driver() - kunit_device_unregister() These helpers allocate a on a 'kunit' bus which will either probe the driver passed in (kunit_device_register_with_driver), or will create a stub driver (kunit_device_register) which is cleaned up on test shutdown. Devices are automatically unregistered on test shutdown, but can be manually unregistered earlier with kunit_device_unregister() in order to, for example, test device release code. Reviewed-by: Matti Vaittinen Reviewed-by: Maxime Ripard Signed-off-by: David Gow Reviewed-by: Greg Kroah-Hartman Signed-off-by: Shuah Khan