// SPDX-License-Identifier: GPL-2.0/* * KUnit test for suppressing warning tracebacks. * * Copyright (C) 2024, Guenter Roeck * Author: Guenter Roeck <linux@roeck-us.net> */ #include <kunit/test.h>#include <linux/bug.h>#include <linux/completion.h>#include <linux/kthread.h> static void backtrace_suppression_test_warn_direct(struct kunit *test){	if (!IS_ENABLED(CONFIG_BUG))		kunit_skip(test, "requires CONFIG_BUG"); 	kunit_warning_suppress(test) {		WARN(1, "This backtrace should be suppressed");		/*		 * Count must be checked inside the scope; the handle		 * is not accessible after the block exits.		 */		KUNIT_EXPECT_SUPPRESSED_WARNING_COUNT(test, 1);	}	KUNIT_EXPECT_FALSE(test, kunit_has_active_suppress_warning());} static noinline void trigger_backtrace_warn(void){	WARN(1, "This backtrace should be suppressed");} static void backtrace_suppression_test_warn_indirect(struct kunit *test){	if (!IS_ENABLED(CONFIG_BUG))		kunit_skip(test, "requires CONFIG_BUG"); 	kunit_warning_suppress(test) {		trigger_backtrace_warn();		KUNIT_EXPECT_SUPPRESSED_WARNING_COUNT(test, 1);	}} static void backtrace_suppression_test_warn_multi(struct kunit *test){	if (!IS_ENABLED(CONFIG_BUG))		kunit_skip(test, "requires CONFIG_BUG"); 	kunit_warning_suppress(test) {		WARN(1, "This backtrace should be suppressed");		trigger_backtrace_warn();		KUNIT_EXPECT_SUPPRESSED_WARNING_COUNT(test, 2);	}} static void backtrace_suppression_test_warn_on_direct(struct kunit *test){	if (!IS_ENABLED(CONFIG_BUG))		kunit_skip(test, "requires CONFIG_BUG");	if (!IS_ENABLED(CONFIG_DEBUG_BUGVERBOSE) && !IS_ENABLED(CONFIG_KALLSYMS))		kunit_skip(test, "requires CONFIG_DEBUG_BUGVERBOSE or CONFIG_KALLSYMS"); 	kunit_warning_suppress(test) {		WARN_ON(1);		KUNIT_EXPECT_SUPPRESSED_WARNING_COUNT(test, 1);	}} static noinline void trigger_backtrace_warn_on(void){	WARN_ON(1);} static void backtrace_suppression_test_warn_on_indirect(struct kunit *test){	if (!IS_ENABLED(CONFIG_BUG))		kunit_skip(test, "requires CONFIG_BUG");	if (!IS_ENABLED(CONFIG_DEBUG_BUGVERBOSE))		kunit_skip(test, "requires CONFIG_DEBUG_BUGVERBOSE"); 	kunit_warning_suppress(test) {		trigger_backtrace_warn_on();		KUNIT_EXPECT_SUPPRESSED_WARNING_COUNT(test, 1);	}} static void backtrace_suppression_test_count(struct kunit *test){	if (!IS_ENABLED(CONFIG_BUG))		kunit_skip(test, "requires CONFIG_BUG"); 	kunit_warning_suppress(test) {		KUNIT_EXPECT_SUPPRESSED_WARNING_COUNT(test, 0); 		WARN(1, "suppressed");		KUNIT_EXPECT_SUPPRESSED_WARNING_COUNT(test, 1); 		WARN(1, "suppressed again");		KUNIT_EXPECT_SUPPRESSED_WARNING_COUNT(test, 2);	}} static void backtrace_suppression_test_active_state(struct kunit *test){	KUNIT_EXPECT_FALSE(test, kunit_has_active_suppress_warning()); 	kunit_warning_suppress(test) {		KUNIT_EXPECT_TRUE(test, kunit_has_active_suppress_warning());	} 	KUNIT_EXPECT_FALSE(test, kunit_has_active_suppress_warning()); 	kunit_warning_suppress(test) {		KUNIT_EXPECT_TRUE(test, kunit_has_active_suppress_warning());	} 	KUNIT_EXPECT_FALSE(test, kunit_has_active_suppress_warning());} static void backtrace_suppression_test_multi_scope(struct kunit *test){	struct kunit_suppressed_warning *sw1, *sw2; 	if (!IS_ENABLED(CONFIG_BUG))		kunit_skip(test, "requires CONFIG_BUG");	if (!IS_ENABLED(CONFIG_DEBUG_BUGVERBOSE))		kunit_skip(test, "requires CONFIG_DEBUG_BUGVERBOSE"); 	sw1 = kunit_start_suppress_warning(test);	trigger_backtrace_warn_on();	WARN(1, "suppressed by sw1");	kunit_end_suppress_warning(test, sw1); 	sw2 = kunit_start_suppress_warning(test);	WARN(1, "suppressed by sw2");	kunit_end_suppress_warning(test, sw2); 	KUNIT_EXPECT_EQ(test, kunit_suppressed_warning_count(sw1), 2);	KUNIT_EXPECT_EQ(test, kunit_suppressed_warning_count(sw2), 1);} struct cross_kthread_data {	bool was_active;	struct completion done;}; static int cross_kthread_fn(void *data){	struct cross_kthread_data *d = data; 	d->was_active = kunit_has_active_suppress_warning();	complete(&d->done);	while (!kthread_should_stop())		schedule();	return 0;} static void backtrace_suppression_test_cross_kthread(struct kunit *test){	struct cross_kthread_data data;	struct task_struct *task; 	data.was_active = false;	init_completion(&data.done); 	kunit_warning_suppress(test) {		task = kthread_run(cross_kthread_fn, &data, "kunit-cross-test");		KUNIT_ASSERT_FALSE(test, IS_ERR(task));		wait_for_completion(&data.done);		kthread_stop(task);	} 	KUNIT_EXPECT_FALSE(test, data.was_active);} static struct kunit_case backtrace_suppression_test_cases[] = {	KUNIT_CASE(backtrace_suppression_test_warn_direct),	KUNIT_CASE(backtrace_suppression_test_warn_indirect),	KUNIT_CASE(backtrace_suppression_test_warn_multi),	KUNIT_CASE(backtrace_suppression_test_warn_on_direct),	KUNIT_CASE(backtrace_suppression_test_warn_on_indirect),	KUNIT_CASE(backtrace_suppression_test_count),	KUNIT_CASE(backtrace_suppression_test_active_state),	KUNIT_CASE(backtrace_suppression_test_multi_scope),	KUNIT_CASE(backtrace_suppression_test_cross_kthread),	{}}; static struct kunit_suite backtrace_suppression_test_suite = {	.name = "backtrace-suppression-test",	.test_cases = backtrace_suppression_test_cases,};kunit_test_suites(&backtrace_suppression_test_suite); MODULE_LICENSE("GPL");MODULE_DESCRIPTION("KUnit test to verify warning backtrace suppression");