// SPDX-License-Identifier: GPL-2.0-only /* * Simple stack backtrace regression test module * * (C) Copyright 2008 Intel Corporation * Author: Arjan van de Ven <arjan@linux.intel.com> */ #include <linux/completion.h> #include <linux/delay.h> #include <linux/interrupt.h> #include <linux/module.h> #include <linux/sched.h> #include <linux/stacktrace.h> static void backtrace_test_normal(void) { pr_info("Testing a backtrace from process context.\n"); pr_info("The following trace is a kernel self test and not a bug!\n"); dump_stack(); } static DECLARE_COMPLETION(backtrace_work); static void backtrace_test_irq_callback(unsigned long data) { dump_stack(); complete(&backtrace_work); } static DECLARE_TASKLET(backtrace_tasklet, &backtrace_test_irq_callback, 0); static void backtrace_test_irq(void) { pr_info("Testing a backtrace from irq context.\n"); pr_info("The following trace is a kernel self test and not a bug!\n"); init_completion(&backtrace_work); tasklet_schedule(&backtrace_tasklet); wait_for_completion(&backtrace_work); } #ifdef CONFIG_STACKTRACE static void backtrace_test_saved(void) { unsigned long entries[8]; unsigned int nr_entries; pr_info("Testing a saved backtrace.\n"); pr_info("The following trace is a kernel self test and not a bug!\n"); nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 0); stack_trace_print(entries, nr_entries, 0); } #else static void backtrace_test_saved(void) { pr_info("Saved backtrace test skipped.\n"); } #endif static int backtrace_regression_test(void) { pr_info("====[ backtrace testing ]===========\n"); backtrace_test_normal(); backtrace_test_irq(); backtrace_test_saved(); pr_info("====[ end of backtrace testing ]====\n"); return 0; } static void exitf(void) { } module_init(backtrace_regression_test); module_exit(exitf); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Arjan van de Ven <arjan@linux.intel.com>");