[GIT PULL] KUnit fixes update for Linux 6.8-rc5

[Shuah Khan]

Hi Linus,

Please pull the following KUnit fixes update for Linux 6.8-rc5.

This KUnit update for Linux 6.8-rc5 consists of one important fix
to unregister kunit_bus when KUnit module is unloaded. Not doing
so causes an error when KUnit module tries to re-register the bus
when it gets reloaded.

diff is attached.

thanks,
-- Shuah

----------------------------------------------------------------
The following changes since commit 1a9f2c776d1416c4ea6cb0d0b9917778c41a1a7d:

  Documentation: KUnit: Update the instructions on how to test static functions (2024-01-22 07:59:03 -0700)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest tags/linux_kselftest-kunit-fixes-6.8-rc5

for you to fetch changes up to 829388b725f8d266ccec32a2f446717d8693eaba:

  kunit: device: Unregister the kunit_bus on shutdown (2024-02-06 17:07:37 -0700)

----------------------------------------------------------------
linux_kselftest-kunit-fixes-6.8-rc5

This KUnit update for Linux 6.8-rc5 consists of one important fix
to unregister kunit_bus when KUnit module is unloaded. Not doing
so causes an error when KUnit module tries to re-register the bus
when it gets reloaded.

----------------------------------------------------------------
David Gow (1):
      kunit: device: Unregister the kunit_bus on shutdown

 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);