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 davidgow@google.com ---
This will hopefully resolve some of the issues linked to from: https://lore.kernel.org/intel-gfx/DM4PR11MB614179CB9C387842D8E8BB40B97C2@DM4...
--- lib/kunit/device-impl.h | 2 ++ lib/kunit/device.c | 14 ++++++++++++++ lib/kunit/test.c | 3 +++ 3 files changed, 19 insertions(+)
diff --git a/lib/kunit/device-impl.h b/lib/kunit/device-impl.h index 54bd55836405..5fcd48ff0f36 100644 --- a/lib/kunit/device-impl.h +++ b/lib/kunit/device-impl.h @@ -13,5 +13,7 @@
// For internal use only -- registers the kunit_bus. int kunit_bus_init(void); +// For internal use only -- unregisters the kunit_bus. +void kunit_bus_shutdown(void);
#endif //_KUNIT_DEVICE_IMPL_H diff --git a/lib/kunit/device.c b/lib/kunit/device.c index 074c6dd2e36a..644a38a1f5b1 100644 --- a/lib/kunit/device.c +++ b/lib/kunit/device.c @@ -54,6 +54,20 @@ int kunit_bus_init(void) return error; }
+/* Unregister the 'kunit_bus' in case the KUnit module is unloaded. */ +void kunit_bus_shutdown(void) +{ + /* Make sure the bus exists before we unregister it. */ + if (IS_ERR_OR_NULL(kunit_bus_device)) + return; + + bus_unregister(&kunit_bus_type); + + root_device_unregister(kunit_bus_device); + + kunit_bus_device = NULL; +} + /* Release a 'fake' KUnit device. */ static void kunit_device_release(struct device *d) { diff --git a/lib/kunit/test.c b/lib/kunit/test.c index 31a5a992e646..1d1475578515 100644 --- a/lib/kunit/test.c +++ b/lib/kunit/test.c @@ -928,6 +928,9 @@ static void __exit kunit_exit(void) #ifdef CONFIG_MODULES unregister_module_notifier(&kunit_mod_nb); #endif + + kunit_bus_shutdown(); + kunit_debugfs_cleanup(); } module_exit(kunit_exit);