Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 923 insertions, 0 deletions

diff --git a/lib/kunit/kunit-test.c b/lib/kunit/kunit-test.c
new file mode 100644
index 000000000..126e30879
--- /dev/null
+++ b/lib/kunit/kunit-test.c
@@ -0,0 +1,923 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit test for core test infrastructure.
+ *
+ * Copyright (C) 2019, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@google.com>
+ */
+#include "linux/gfp_types.h"
+#include <kunit/test.h>
+#include <kunit/test-bug.h>
+#include <kunit/static_stub.h>
+
+#include <linux/device.h>
+#include <kunit/device.h>
+
+#include "string-stream.h"
+#include "try-catch-impl.h"
+
+struct kunit_try_catch_test_context {
+	struct kunit_try_catch *try_catch;
+	bool function_called;
+};
+
+static void kunit_test_successful_try(void *data)
+{
+	struct kunit *test = data;
+	struct kunit_try_catch_test_context *ctx = test->priv;
+
+	ctx->function_called = true;
+}
+
+static void kunit_test_no_catch(void *data)
+{
+	struct kunit *test = data;
+
+	KUNIT_FAIL(test, "Catch should not be called\n");
+}
+
+static void kunit_test_try_catch_successful_try_no_catch(struct kunit *test)
+{
+	struct kunit_try_catch_test_context *ctx = test->priv;
+	struct kunit_try_catch *try_catch = ctx->try_catch;
+
+	kunit_try_catch_init(try_catch,
+			     test,
+			     kunit_test_successful_try,
+			     kunit_test_no_catch,
+			     300 * msecs_to_jiffies(MSEC_PER_SEC));
+	kunit_try_catch_run(try_catch, test);
+
+	KUNIT_EXPECT_TRUE(test, ctx->function_called);
+}
+
+static void kunit_test_unsuccessful_try(void *data)
+{
+	struct kunit *test = data;
+	struct kunit_try_catch_test_context *ctx = test->priv;
+	struct kunit_try_catch *try_catch = ctx->try_catch;
+
+	kunit_try_catch_throw(try_catch);
+	KUNIT_FAIL(test, "This line should never be reached\n");
+}
+
+static void kunit_test_catch(void *data)
+{
+	struct kunit *test = data;
+	struct kunit_try_catch_test_context *ctx = test->priv;
+
+	ctx->function_called = true;
+}
+
+static void kunit_test_try_catch_unsuccessful_try_does_catch(struct kunit *test)
+{
+	struct kunit_try_catch_test_context *ctx = test->priv;
+	struct kunit_try_catch *try_catch = ctx->try_catch;
+
+	kunit_try_catch_init(try_catch,
+			     test,
+			     kunit_test_unsuccessful_try,
+			     kunit_test_catch,
+			     300 * msecs_to_jiffies(MSEC_PER_SEC));
+	kunit_try_catch_run(try_catch, test);
+
+	KUNIT_EXPECT_TRUE(test, ctx->function_called);
+}
+
+static int kunit_try_catch_test_init(struct kunit *test)
+{
+	struct kunit_try_catch_test_context *ctx;
+
+	ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+	test->priv = ctx;
+
+	ctx->try_catch = kunit_kmalloc(test,
+				       sizeof(*ctx->try_catch),
+				       GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx->try_catch);
+
+	return 0;
+}
+
+static struct kunit_case kunit_try_catch_test_cases[] = {
+	KUNIT_CASE(kunit_test_try_catch_successful_try_no_catch),
+	KUNIT_CASE(kunit_test_try_catch_unsuccessful_try_does_catch),
+	{}
+};
+
+static struct kunit_suite kunit_try_catch_test_suite = {
+	.name = "kunit-try-catch-test",
+	.init = kunit_try_catch_test_init,
+	.test_cases = kunit_try_catch_test_cases,
+};
+
+#if IS_ENABLED(CONFIG_KUNIT_FAULT_TEST)
+
+static void kunit_test_null_dereference(void *data)
+{
+	struct kunit *test = data;
+	int *null = NULL;
+
+	*null = 0;
+
+	KUNIT_FAIL(test, "This line should never be reached\n");
+}
+
+static void kunit_test_fault_null_dereference(struct kunit *test)
+{
+	struct kunit_try_catch_test_context *ctx = test->priv;
+	struct kunit_try_catch *try_catch = ctx->try_catch;
+
+	kunit_try_catch_init(try_catch,
+			     test,
+			     kunit_test_null_dereference,
+			     kunit_test_catch,
+			     300 * msecs_to_jiffies(MSEC_PER_SEC));
+	kunit_try_catch_run(try_catch, test);
+
+	KUNIT_EXPECT_EQ(test, try_catch->try_result, -EINTR);
+	KUNIT_EXPECT_TRUE(test, ctx->function_called);
+}
+
+#endif /* CONFIG_KUNIT_FAULT_TEST */
+
+static struct kunit_case kunit_fault_test_cases[] = {
+#if IS_ENABLED(CONFIG_KUNIT_FAULT_TEST)
+	KUNIT_CASE(kunit_test_fault_null_dereference),
+#endif /* CONFIG_KUNIT_FAULT_TEST */
+	{}
+};
+
+static struct kunit_suite kunit_fault_test_suite = {
+	.name = "kunit_fault",
+	.init = kunit_try_catch_test_init,
+	.test_cases = kunit_fault_test_cases,
+};
+
+/*
+ * Context for testing test managed resources
+ * is_resource_initialized is used to test arbitrary resources
+ */
+struct kunit_test_resource_context {
+	struct kunit test;
+	bool is_resource_initialized;
+	int allocate_order[2];
+	int free_order[4];
+};
+
+static int fake_resource_init(struct kunit_resource *res, void *context)
+{
+	struct kunit_test_resource_context *ctx = context;
+
+	res->data = &ctx->is_resource_initialized;
+	ctx->is_resource_initialized = true;
+	return 0;
+}
+
+static void fake_resource_free(struct kunit_resource *res)
+{
+	bool *is_resource_initialized = res->data;
+
+	*is_resource_initialized = false;
+}
+
+static void kunit_resource_test_init_resources(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx = test->priv;
+
+	kunit_init_test(&ctx->test, "testing_test_init_test", NULL);
+
+	KUNIT_EXPECT_TRUE(test, list_empty(&ctx->test.resources));
+}
+
+static void kunit_resource_test_alloc_resource(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx = test->priv;
+	struct kunit_resource *res;
+	kunit_resource_free_t free = fake_resource_free;
+
+	res = kunit_alloc_and_get_resource(&ctx->test,
+					   fake_resource_init,
+					   fake_resource_free,
+					   GFP_KERNEL,
+					   ctx);
+
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, res);
+	KUNIT_EXPECT_PTR_EQ(test,
+			    &ctx->is_resource_initialized,
+			    (bool *)res->data);
+	KUNIT_EXPECT_TRUE(test, list_is_last(&res->node, &ctx->test.resources));
+	KUNIT_EXPECT_PTR_EQ(test, free, res->free);
+
+	kunit_put_resource(res);
+}
+
+static inline bool kunit_resource_instance_match(struct kunit *test,
+						 struct kunit_resource *res,
+						 void *match_data)
+{
+	return res->data == match_data;
+}
+
+/*
+ * Note: tests below use kunit_alloc_and_get_resource(), so as a consequence
+ * they have a reference to the associated resource that they must release
+ * via kunit_put_resource().  In normal operation, users will only
+ * have to do this for cases where they use kunit_find_resource(), and the
+ * kunit_alloc_resource() function will be used (which does not take a
+ * resource reference).
+ */
+static void kunit_resource_test_destroy_resource(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx = test->priv;
+	struct kunit_resource *res = kunit_alloc_and_get_resource(
+			&ctx->test,
+			fake_resource_init,
+			fake_resource_free,
+			GFP_KERNEL,
+			ctx);
+
+	kunit_put_resource(res);
+
+	KUNIT_ASSERT_FALSE(test,
+			   kunit_destroy_resource(&ctx->test,
+						  kunit_resource_instance_match,
+						  res->data));
+
+	KUNIT_EXPECT_FALSE(test, ctx->is_resource_initialized);
+	KUNIT_EXPECT_TRUE(test, list_empty(&ctx->test.resources));
+}
+
+static void kunit_resource_test_remove_resource(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx = test->priv;
+	struct kunit_resource *res = kunit_alloc_and_get_resource(
+			&ctx->test,
+			fake_resource_init,
+			fake_resource_free,
+			GFP_KERNEL,
+			ctx);
+
+	/* The resource is in the list */
+	KUNIT_EXPECT_FALSE(test, list_empty(&ctx->test.resources));
+
+	/* Remove the resource. The pointer is still valid, but it can't be
+	 * found.
+	 */
+	kunit_remove_resource(test, res);
+	KUNIT_EXPECT_TRUE(test, list_empty(&ctx->test.resources));
+	/* We haven't been freed yet. */
+	KUNIT_EXPECT_TRUE(test, ctx->is_resource_initialized);
+
+	/* Removing the resource multiple times is valid. */
+	kunit_remove_resource(test, res);
+	KUNIT_EXPECT_TRUE(test, list_empty(&ctx->test.resources));
+	/* Despite having been removed twice (from only one reference), the
+	 * resource still has not been freed.
+	 */
+	KUNIT_EXPECT_TRUE(test, ctx->is_resource_initialized);
+
+	/* Free the resource. */
+	kunit_put_resource(res);
+	KUNIT_EXPECT_FALSE(test, ctx->is_resource_initialized);
+}
+
+static void kunit_resource_test_cleanup_resources(struct kunit *test)
+{
+	int i;
+	struct kunit_test_resource_context *ctx = test->priv;
+	struct kunit_resource *resources[5];
+
+	for (i = 0; i < ARRAY_SIZE(resources); i++) {
+		resources[i] = kunit_alloc_and_get_resource(&ctx->test,
+							    fake_resource_init,
+							    fake_resource_free,
+							    GFP_KERNEL,
+							    ctx);
+		kunit_put_resource(resources[i]);
+	}
+
+	kunit_cleanup(&ctx->test);
+
+	KUNIT_EXPECT_TRUE(test, list_empty(&ctx->test.resources));
+}
+
+static void kunit_resource_test_mark_order(int order_array[],
+					   size_t order_size,
+					   int key)
+{
+	int i;
+
+	for (i = 0; i < order_size && order_array[i]; i++)
+		;
+
+	order_array[i] = key;
+}
+
+#define KUNIT_RESOURCE_TEST_MARK_ORDER(ctx, order_field, key)		       \
+		kunit_resource_test_mark_order(ctx->order_field,	       \
+					       ARRAY_SIZE(ctx->order_field),   \
+					       key)
+
+static int fake_resource_2_init(struct kunit_resource *res, void *context)
+{
+	struct kunit_test_resource_context *ctx = context;
+
+	KUNIT_RESOURCE_TEST_MARK_ORDER(ctx, allocate_order, 2);
+
+	res->data = ctx;
+
+	return 0;
+}
+
+static void fake_resource_2_free(struct kunit_resource *res)
+{
+	struct kunit_test_resource_context *ctx = res->data;
+
+	KUNIT_RESOURCE_TEST_MARK_ORDER(ctx, free_order, 2);
+}
+
+static int fake_resource_1_init(struct kunit_resource *res, void *context)
+{
+	struct kunit_test_resource_context *ctx = context;
+	struct kunit_resource *res2;
+
+	res2 = kunit_alloc_and_get_resource(&ctx->test,
+					    fake_resource_2_init,
+					    fake_resource_2_free,
+					    GFP_KERNEL,
+					    ctx);
+
+	KUNIT_RESOURCE_TEST_MARK_ORDER(ctx, allocate_order, 1);
+
+	res->data = ctx;
+
+	kunit_put_resource(res2);
+
+	return 0;
+}
+
+static void fake_resource_1_free(struct kunit_resource *res)
+{
+	struct kunit_test_resource_context *ctx = res->data;
+
+	KUNIT_RESOURCE_TEST_MARK_ORDER(ctx, free_order, 1);
+}
+
+/*
+ * TODO(brendanhiggins@google.com): replace the arrays that keep track of the
+ * order of allocation and freeing with strict mocks using the IN_SEQUENCE macro
+ * to assert allocation and freeing order when the feature becomes available.
+ */
+static void kunit_resource_test_proper_free_ordering(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx = test->priv;
+	struct kunit_resource *res;
+
+	/* fake_resource_1 allocates a fake_resource_2 in its init. */
+	res = kunit_alloc_and_get_resource(&ctx->test,
+					   fake_resource_1_init,
+					   fake_resource_1_free,
+					   GFP_KERNEL,
+					   ctx);
+
+	/*
+	 * Since fake_resource_2_init calls KUNIT_RESOURCE_TEST_MARK_ORDER
+	 * before returning to fake_resource_1_init, it should be the first to
+	 * put its key in the allocate_order array.
+	 */
+	KUNIT_EXPECT_EQ(test, ctx->allocate_order[0], 2);
+	KUNIT_EXPECT_EQ(test, ctx->allocate_order[1], 1);
+
+	kunit_put_resource(res);
+
+	kunit_cleanup(&ctx->test);
+
+	/*
+	 * Because fake_resource_2 finishes allocation before fake_resource_1,
+	 * fake_resource_1 should be freed first since it could depend on
+	 * fake_resource_2.
+	 */
+	KUNIT_EXPECT_EQ(test, ctx->free_order[0], 1);
+	KUNIT_EXPECT_EQ(test, ctx->free_order[1], 2);
+}
+
+static void kunit_resource_test_static(struct kunit *test)
+{
+	struct kunit_test_resource_context ctx;
+	struct kunit_resource res;
+
+	KUNIT_EXPECT_EQ(test, kunit_add_resource(test, NULL, NULL, &res, &ctx),
+			0);
+
+	KUNIT_EXPECT_PTR_EQ(test, res.data, (void *)&ctx);
+
+	kunit_cleanup(test);
+
+	KUNIT_EXPECT_TRUE(test, list_empty(&test->resources));
+}
+
+static void kunit_resource_test_named(struct kunit *test)
+{
+	struct kunit_resource res1, res2, *found = NULL;
+	struct kunit_test_resource_context ctx;
+
+	KUNIT_EXPECT_EQ(test,
+			kunit_add_named_resource(test, NULL, NULL, &res1,
+						 "resource_1", &ctx),
+			0);
+	KUNIT_EXPECT_PTR_EQ(test, res1.data, (void *)&ctx);
+
+	KUNIT_EXPECT_EQ(test,
+			kunit_add_named_resource(test, NULL, NULL, &res1,
+						 "resource_1", &ctx),
+			-EEXIST);
+
+	KUNIT_EXPECT_EQ(test,
+			kunit_add_named_resource(test, NULL, NULL, &res2,
+						 "resource_2", &ctx),
+			0);
+
+	found = kunit_find_named_resource(test, "resource_1");
+
+	KUNIT_EXPECT_PTR_EQ(test, found, &res1);
+
+	if (found)
+		kunit_put_resource(&res1);
+
+	KUNIT_EXPECT_EQ(test, kunit_destroy_named_resource(test, "resource_2"),
+			0);
+
+	kunit_cleanup(test);
+
+	KUNIT_EXPECT_TRUE(test, list_empty(&test->resources));
+}
+
+static void increment_int(void *ctx)
+{
+	int *i = (int *)ctx;
+	(*i)++;
+}
+
+static void kunit_resource_test_action(struct kunit *test)
+{
+	int num_actions = 0;
+
+	kunit_add_action(test, increment_int, &num_actions);
+	KUNIT_EXPECT_EQ(test, num_actions, 0);
+	kunit_cleanup(test);
+	KUNIT_EXPECT_EQ(test, num_actions, 1);
+
+	/* Once we've cleaned up, the action queue is empty. */
+	kunit_cleanup(test);
+	KUNIT_EXPECT_EQ(test, num_actions, 1);
+
+	/* Check the same function can be deferred multiple times. */
+	kunit_add_action(test, increment_int, &num_actions);
+	kunit_add_action(test, increment_int, &num_actions);
+	kunit_cleanup(test);
+	KUNIT_EXPECT_EQ(test, num_actions, 3);
+}
+static void kunit_resource_test_remove_action(struct kunit *test)
+{
+	int num_actions = 0;
+
+	kunit_add_action(test, increment_int, &num_actions);
+	KUNIT_EXPECT_EQ(test, num_actions, 0);
+
+	kunit_remove_action(test, increment_int, &num_actions);
+	kunit_cleanup(test);
+	KUNIT_EXPECT_EQ(test, num_actions, 0);
+}
+static void kunit_resource_test_release_action(struct kunit *test)
+{
+	int num_actions = 0;
+
+	kunit_add_action(test, increment_int, &num_actions);
+	KUNIT_EXPECT_EQ(test, num_actions, 0);
+	/* Runs immediately on trigger. */
+	kunit_release_action(test, increment_int, &num_actions);
+	KUNIT_EXPECT_EQ(test, num_actions, 1);
+
+	/* Doesn't run again on test exit. */
+	kunit_cleanup(test);
+	KUNIT_EXPECT_EQ(test, num_actions, 1);
+}
+static void action_order_1(void *ctx)
+{
+	struct kunit_test_resource_context *res_ctx = (struct kunit_test_resource_context *)ctx;
+
+	KUNIT_RESOURCE_TEST_MARK_ORDER(res_ctx, free_order, 1);
+	kunit_log(KERN_INFO, current->kunit_test, "action_order_1");
+}
+static void action_order_2(void *ctx)
+{
+	struct kunit_test_resource_context *res_ctx = (struct kunit_test_resource_context *)ctx;
+
+	KUNIT_RESOURCE_TEST_MARK_ORDER(res_ctx, free_order, 2);
+	kunit_log(KERN_INFO, current->kunit_test, "action_order_2");
+}
+static void kunit_resource_test_action_ordering(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx = test->priv;
+
+	kunit_add_action(test, action_order_1, ctx);
+	kunit_add_action(test, action_order_2, ctx);
+	kunit_add_action(test, action_order_1, ctx);
+	kunit_add_action(test, action_order_2, ctx);
+	kunit_remove_action(test, action_order_1, ctx);
+	kunit_release_action(test, action_order_2, ctx);
+	kunit_cleanup(test);
+
+	/* [2 is triggered] [2], [(1 is cancelled)] [1] */
+	KUNIT_EXPECT_EQ(test, ctx->free_order[0], 2);
+	KUNIT_EXPECT_EQ(test, ctx->free_order[1], 2);
+	KUNIT_EXPECT_EQ(test, ctx->free_order[2], 1);
+}
+
+static int kunit_resource_test_init(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx = kzalloc_obj(*ctx);
+
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
+	test->priv = ctx;
+
+	kunit_init_test(&ctx->test, "test_test_context", NULL);
+
+	return 0;
+}
+
+static void kunit_resource_test_exit(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx = test->priv;
+
+	kunit_cleanup(&ctx->test);
+	kfree(ctx);
+}
+
+static struct kunit_case kunit_resource_test_cases[] = {
+	KUNIT_CASE(kunit_resource_test_init_resources),
+	KUNIT_CASE(kunit_resource_test_alloc_resource),
+	KUNIT_CASE(kunit_resource_test_destroy_resource),
+	KUNIT_CASE(kunit_resource_test_remove_resource),
+	KUNIT_CASE(kunit_resource_test_cleanup_resources),
+	KUNIT_CASE(kunit_resource_test_proper_free_ordering),
+	KUNIT_CASE(kunit_resource_test_static),
+	KUNIT_CASE(kunit_resource_test_named),
+	KUNIT_CASE(kunit_resource_test_action),
+	KUNIT_CASE(kunit_resource_test_remove_action),
+	KUNIT_CASE(kunit_resource_test_release_action),
+	KUNIT_CASE(kunit_resource_test_action_ordering),
+	{}
+};
+
+static struct kunit_suite kunit_resource_test_suite = {
+	.name = "kunit-resource-test",
+	.init = kunit_resource_test_init,
+	.exit = kunit_resource_test_exit,
+	.test_cases = kunit_resource_test_cases,
+};
+
+/*
+ * Log tests call string_stream functions, which aren't exported. So only
+ * build this code if this test is built-in.
+ */
+#if IS_BUILTIN(CONFIG_KUNIT_TEST)
+
+/* This avoids a cast warning if kfree() is passed direct to kunit_add_action(). */
+KUNIT_DEFINE_ACTION_WRAPPER(kfree_wrapper, kfree, const void *);
+
+static void kunit_log_test(struct kunit *test)
+{
+	struct kunit_suite suite;
+#ifdef CONFIG_KUNIT_DEBUGFS
+	char *full_log;
+#endif
+	suite.log = kunit_alloc_string_stream(test, GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, suite.log);
+	string_stream_set_append_newlines(suite.log, true);
+
+	kunit_log(KERN_INFO, test, "put this in log.");
+	kunit_log(KERN_INFO, test, "this too.");
+	kunit_log(KERN_INFO, &suite, "add to suite log.");
+	kunit_log(KERN_INFO, &suite, "along with this.");
+
+#ifdef CONFIG_KUNIT_DEBUGFS
+	KUNIT_EXPECT_TRUE(test, test->log->append_newlines);
+
+	full_log = string_stream_get_string(test->log);
+	kunit_add_action(test, kfree_wrapper, full_log);
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test,
+				     strstr(full_log, "put this in log."));
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test,
+				     strstr(full_log, "this too."));
+
+	full_log = string_stream_get_string(suite.log);
+	kunit_add_action(test, kfree_wrapper, full_log);
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test,
+				     strstr(full_log, "add to suite log."));
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test,
+				     strstr(full_log, "along with this."));
+#else
+	KUNIT_EXPECT_NULL(test, test->log);
+#endif
+}
+
+static void kunit_log_newline_test(struct kunit *test)
+{
+	char *full_log;
+
+	kunit_info(test, "Add newline\n");
+	if (test->log) {
+		full_log = string_stream_get_string(test->log);
+		kunit_add_action(test, kfree_wrapper, full_log);
+		KUNIT_ASSERT_NOT_NULL_MSG(test, strstr(full_log, "Add newline\n"),
+			"Missing log line, full log:\n%s", full_log);
+		KUNIT_EXPECT_NULL(test, strstr(full_log, "Add newline\n\n"));
+	} else {
+		kunit_skip(test, "only useful when debugfs is enabled");
+	}
+}
+#else
+static void kunit_log_test(struct kunit *test)
+{
+	kunit_skip(test, "Log tests only run when built-in");
+}
+
+static void kunit_log_newline_test(struct kunit *test)
+{
+	kunit_skip(test, "Log tests only run when built-in");
+}
+#endif /* IS_BUILTIN(CONFIG_KUNIT_TEST) */
+
+static struct kunit_case kunit_log_test_cases[] = {
+	KUNIT_CASE(kunit_log_test),
+	KUNIT_CASE(kunit_log_newline_test),
+	{}
+};
+
+static struct kunit_suite kunit_log_test_suite = {
+	.name = "kunit-log-test",
+	.test_cases = kunit_log_test_cases,
+};
+
+static void kunit_status_set_failure_test(struct kunit *test)
+{
+	struct kunit fake;
+
+	kunit_init_test(&fake, "fake test", NULL);
+
+	KUNIT_EXPECT_EQ(test, fake.status, (enum kunit_status)KUNIT_SUCCESS);
+	kunit_set_failure(&fake);
+	KUNIT_EXPECT_EQ(test, fake.status, (enum kunit_status)KUNIT_FAILURE);
+}
+
+static void kunit_status_mark_skipped_test(struct kunit *test)
+{
+	struct kunit fake;
+
+	kunit_init_test(&fake, "fake test", NULL);
+
+	/* Before: Should be SUCCESS with no comment. */
+	KUNIT_EXPECT_EQ(test, fake.status, KUNIT_SUCCESS);
+	KUNIT_EXPECT_STREQ(test, fake.status_comment, "");
+
+	/* Mark the test as skipped. */
+	kunit_mark_skipped(&fake, "Accepts format string: %s", "YES");
+
+	/* After: Should be SKIPPED with our comment. */
+	KUNIT_EXPECT_EQ(test, fake.status, (enum kunit_status)KUNIT_SKIPPED);
+	KUNIT_EXPECT_STREQ(test, fake.status_comment, "Accepts format string: YES");
+}
+
+static struct kunit_case kunit_status_test_cases[] = {
+	KUNIT_CASE(kunit_status_set_failure_test),
+	KUNIT_CASE(kunit_status_mark_skipped_test),
+	{}
+};
+
+static struct kunit_suite kunit_status_test_suite = {
+	.name = "kunit_status",
+	.test_cases = kunit_status_test_cases,
+};
+
+static void kunit_current_test(struct kunit *test)
+{
+	/* Check results of both current->kunit_test and
+	 * kunit_get_current_test() are equivalent to current test.
+	 */
+	KUNIT_EXPECT_PTR_EQ(test, test, current->kunit_test);
+	KUNIT_EXPECT_PTR_EQ(test, test, kunit_get_current_test());
+}
+
+static void kunit_current_fail_test(struct kunit *test)
+{
+	struct kunit fake;
+
+	kunit_init_test(&fake, "fake test", NULL);
+	KUNIT_EXPECT_EQ(test, fake.status, KUNIT_SUCCESS);
+
+	/* Set current->kunit_test to fake test. */
+	current->kunit_test = &fake;
+
+	kunit_fail_current_test("This should make `fake` test fail.");
+	KUNIT_EXPECT_EQ(test, fake.status, (enum kunit_status)KUNIT_FAILURE);
+	kunit_cleanup(&fake);
+
+	/* Reset current->kunit_test to current test. */
+	current->kunit_test = test;
+}
+
+static struct kunit_case kunit_current_test_cases[] = {
+	KUNIT_CASE(kunit_current_test),
+	KUNIT_CASE(kunit_current_fail_test),
+	{}
+};
+
+static void test_dev_action(void *priv)
+{
+	*(long *)priv = 1;
+}
+
+static void kunit_device_test(struct kunit *test)
+{
+	struct device *test_device;
+	long action_was_run = 0;
+
+	test_device = kunit_device_register(test, "my_device");
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, test_device);
+
+	// Add an action to verify cleanup.
+	devm_add_action(test_device, test_dev_action, &action_was_run);
+
+	KUNIT_EXPECT_EQ(test, action_was_run, 0);
+
+	kunit_device_unregister(test, test_device);
+
+	KUNIT_EXPECT_EQ(test, action_was_run, 1);
+}
+
+static void kunit_device_cleanup_test(struct kunit *test)
+{
+	struct device *test_device;
+	long action_was_run = 0;
+
+	test_device = kunit_device_register(test, "my_device");
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, test_device);
+
+	/* Add an action to verify cleanup. */
+	devm_add_action(test_device, test_dev_action, &action_was_run);
+
+	KUNIT_EXPECT_EQ(test, action_was_run, 0);
+
+	/* Force KUnit to run cleanup early. */
+	kunit_cleanup(test);
+
+	KUNIT_EXPECT_EQ(test, action_was_run, 1);
+}
+
+struct driver_test_state {
+	bool driver_device_probed;
+	bool driver_device_removed;
+	long action_was_run;
+};
+
+static int driver_probe_hook(struct device *dev)
+{
+	struct kunit *test = kunit_get_current_test();
+	struct driver_test_state *state = (struct driver_test_state *)test->priv;
+
+	state->driver_device_probed = true;
+	return 0;
+}
+
+static int driver_remove_hook(struct device *dev)
+{
+	struct kunit *test = kunit_get_current_test();
+	struct driver_test_state *state = (struct driver_test_state *)test->priv;
+
+	state->driver_device_removed = true;
+	return 0;
+}
+
+static void kunit_device_driver_test(struct kunit *test)
+{
+	struct device_driver *test_driver;
+	struct device *test_device;
+	struct driver_test_state *test_state = kunit_kzalloc(test, sizeof(*test_state), GFP_KERNEL);
+
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, test_state);
+
+	test->priv = test_state;
+	test_driver = kunit_driver_create(test, "my_driver");
+
+	// This can fail with an error pointer.
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, test_driver);
+
+	test_driver->probe = driver_probe_hook;
+	test_driver->remove = driver_remove_hook;
+
+	test_device = kunit_device_register_with_driver(test, "my_device", test_driver);
+
+	// This can fail with an error pointer.
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, test_device);
+
+	// Make sure the probe function was called.
+	KUNIT_ASSERT_TRUE(test, test_state->driver_device_probed);
+
+	// Add an action to verify cleanup.
+	devm_add_action(test_device, test_dev_action, &test_state->action_was_run);
+
+	KUNIT_EXPECT_EQ(test, test_state->action_was_run, 0);
+
+	kunit_device_unregister(test, test_device);
+	test_device = NULL;
+
+	// Make sure the remove hook was called.
+	KUNIT_ASSERT_TRUE(test, test_state->driver_device_removed);
+
+	// We're going to test this again.
+	test_state->driver_device_probed = false;
+
+	// The driver should not automatically be destroyed by
+	// kunit_device_unregister, so we can re-use it.
+	test_device = kunit_device_register_with_driver(test, "my_device", test_driver);
+
+	// This can fail with an error pointer.
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, test_device);
+
+	// Probe was called again.
+	KUNIT_ASSERT_TRUE(test, test_state->driver_device_probed);
+
+	// Everything is automatically freed here.
+}
+
+static struct kunit_case kunit_device_test_cases[] = {
+	KUNIT_CASE(kunit_device_test),
+	KUNIT_CASE(kunit_device_cleanup_test),
+	KUNIT_CASE(kunit_device_driver_test),
+	{}
+};
+
+static struct kunit_suite kunit_device_test_suite = {
+	.name = "kunit_device",
+	.test_cases = kunit_device_test_cases,
+};
+
+static struct kunit_suite kunit_current_test_suite = {
+	.name = "kunit_current",
+	.test_cases = kunit_current_test_cases,
+};
+
+static void kunit_stub_test(struct kunit *test)
+{
+	struct kunit fake_test;
+	const unsigned long fake_real_fn_addr = 0x1234;
+	const unsigned long fake_replacement_addr = 0x5678;
+	struct kunit_resource *res;
+	struct {
+		void *real_fn_addr;
+		void *replacement_addr;
+	} *stub_ctx;
+
+	kunit_init_test(&fake_test, "kunit_stub_fake_test", NULL);
+	KUNIT_ASSERT_EQ(test, fake_test.status, KUNIT_SUCCESS);
+	KUNIT_ASSERT_EQ(test, list_count_nodes(&fake_test.resources), 0);
+
+	__kunit_activate_static_stub(&fake_test, (void *)fake_real_fn_addr,
+				     (void *)fake_replacement_addr);
+	KUNIT_ASSERT_EQ(test, fake_test.status, KUNIT_SUCCESS);
+	KUNIT_ASSERT_EQ(test, list_count_nodes(&fake_test.resources), 1);
+
+	res = list_first_entry(&fake_test.resources, struct kunit_resource, node);
+	KUNIT_EXPECT_NOT_NULL(test, res);
+
+	stub_ctx = res->data;
+	KUNIT_EXPECT_NOT_NULL(test, stub_ctx);
+	KUNIT_EXPECT_EQ(test, (unsigned long)stub_ctx->real_fn_addr, fake_real_fn_addr);
+	KUNIT_EXPECT_EQ(test, (unsigned long)stub_ctx->replacement_addr, fake_replacement_addr);
+
+	__kunit_activate_static_stub(&fake_test, (void *)fake_real_fn_addr, NULL);
+	KUNIT_ASSERT_EQ(test, fake_test.status, KUNIT_SUCCESS);
+	KUNIT_ASSERT_EQ(test, list_count_nodes(&fake_test.resources), 0);
+}
+
+static struct kunit_case kunit_stub_test_cases[] = {
+	KUNIT_CASE(kunit_stub_test),
+	{}
+};
+
+static struct kunit_suite kunit_stub_test_suite = {
+	.name = "kunit_stub",
+	.test_cases = kunit_stub_test_cases,
+};
+
+kunit_test_suites(&kunit_try_catch_test_suite, &kunit_resource_test_suite,
+		  &kunit_log_test_suite, &kunit_status_test_suite,
+		  &kunit_current_test_suite, &kunit_device_test_suite,
+		  &kunit_fault_test_suite, &kunit_stub_test_suite);
+
+MODULE_DESCRIPTION("KUnit test for core test infrastructure");
+MODULE_LICENSE("GPL v2");