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- // SPDX-License-Identifier: GPL-2.0-only
- /*
- * linux/kernel/panic.c
- *
- * Copyright (C) 1991, 1992 Linus Torvalds
- */
- /*
- * This function is used through-out the kernel (including mm and fs)
- * to indicate a major problem.
- */
- #include <linux/debug_locks.h>
- #include <linux/sched/debug.h>
- #include <linux/interrupt.h>
- #include <linux/kgdb.h>
- #include <linux/kmsg_dump.h>
- #include <linux/kallsyms.h>
- #include <linux/notifier.h>
- #include <linux/vt_kern.h>
- #include <linux/module.h>
- #include <linux/random.h>
- #include <linux/ftrace.h>
- #include <linux/reboot.h>
- #include <linux/delay.h>
- #include <linux/kexec.h>
- #include <linux/panic_notifier.h>
- #include <linux/sched.h>
- #include <linux/sysrq.h>
- #include <linux/init.h>
- #include <linux/nmi.h>
- #include <linux/console.h>
- #include <linux/bug.h>
- #include <linux/ratelimit.h>
- #include <linux/debugfs.h>
- #include <linux/sysfs.h>
- #include <linux/context_tracking.h>
- #include <trace/events/error_report.h>
- #include <asm/sections.h>
- #define PANIC_TIMER_STEP 100
- #define PANIC_BLINK_SPD 18
- #ifdef CONFIG_SMP
- /*
- * Should we dump all CPUs backtraces in an oops event?
- * Defaults to 0, can be changed via sysctl.
- */
- static unsigned int __read_mostly sysctl_oops_all_cpu_backtrace;
- #else
- #define sysctl_oops_all_cpu_backtrace 0
- #endif /* CONFIG_SMP */
- int panic_on_oops = CONFIG_PANIC_ON_OOPS_VALUE;
- static unsigned long tainted_mask =
- IS_ENABLED(CONFIG_RANDSTRUCT) ? (1 << TAINT_RANDSTRUCT) : 0;
- static int pause_on_oops;
- static int pause_on_oops_flag;
- static DEFINE_SPINLOCK(pause_on_oops_lock);
- bool crash_kexec_post_notifiers;
- int panic_on_warn __read_mostly;
- unsigned long panic_on_taint;
- bool panic_on_taint_nousertaint = false;
- static unsigned int warn_limit __read_mostly;
- int panic_timeout = CONFIG_PANIC_TIMEOUT;
- EXPORT_SYMBOL_GPL(panic_timeout);
- #define PANIC_PRINT_TASK_INFO 0x00000001
- #define PANIC_PRINT_MEM_INFO 0x00000002
- #define PANIC_PRINT_TIMER_INFO 0x00000004
- #define PANIC_PRINT_LOCK_INFO 0x00000008
- #define PANIC_PRINT_FTRACE_INFO 0x00000010
- #define PANIC_PRINT_ALL_PRINTK_MSG 0x00000020
- #define PANIC_PRINT_ALL_CPU_BT 0x00000040
- unsigned long panic_print;
- ATOMIC_NOTIFIER_HEAD(panic_notifier_list);
- EXPORT_SYMBOL(panic_notifier_list);
- #ifdef CONFIG_SYSCTL
- static struct ctl_table kern_panic_table[] = {
- #ifdef CONFIG_SMP
- {
- .procname = "oops_all_cpu_backtrace",
- .data = &sysctl_oops_all_cpu_backtrace,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_ONE,
- },
- #endif
- {
- .procname = "warn_limit",
- .data = &warn_limit,
- .maxlen = sizeof(warn_limit),
- .mode = 0644,
- .proc_handler = proc_douintvec,
- },
- { }
- };
- static __init int kernel_panic_sysctls_init(void)
- {
- register_sysctl_init("kernel", kern_panic_table);
- return 0;
- }
- late_initcall(kernel_panic_sysctls_init);
- #endif
- static atomic_t warn_count = ATOMIC_INIT(0);
- #ifdef CONFIG_SYSFS
- static ssize_t warn_count_show(struct kobject *kobj, struct kobj_attribute *attr,
- char *page)
- {
- return sysfs_emit(page, "%d\n", atomic_read(&warn_count));
- }
- static struct kobj_attribute warn_count_attr = __ATTR_RO(warn_count);
- static __init int kernel_panic_sysfs_init(void)
- {
- sysfs_add_file_to_group(kernel_kobj, &warn_count_attr.attr, NULL);
- return 0;
- }
- late_initcall(kernel_panic_sysfs_init);
- #endif
- static long no_blink(int state)
- {
- return 0;
- }
- /* Returns how long it waited in ms */
- long (*panic_blink)(int state);
- EXPORT_SYMBOL(panic_blink);
- /*
- * Stop ourself in panic -- architecture code may override this
- */
- void __weak panic_smp_self_stop(void)
- {
- while (1)
- cpu_relax();
- }
- /*
- * Stop ourselves in NMI context if another CPU has already panicked. Arch code
- * may override this to prepare for crash dumping, e.g. save regs info.
- */
- void __weak nmi_panic_self_stop(struct pt_regs *regs)
- {
- panic_smp_self_stop();
- }
- /*
- * Stop other CPUs in panic. Architecture dependent code may override this
- * with more suitable version. For example, if the architecture supports
- * crash dump, it should save registers of each stopped CPU and disable
- * per-CPU features such as virtualization extensions.
- */
- void __weak crash_smp_send_stop(void)
- {
- static int cpus_stopped;
- /*
- * This function can be called twice in panic path, but obviously
- * we execute this only once.
- */
- if (cpus_stopped)
- return;
- /*
- * Note smp_send_stop is the usual smp shutdown function, which
- * unfortunately means it may not be hardened to work in a panic
- * situation.
- */
- smp_send_stop();
- cpus_stopped = 1;
- }
- atomic_t panic_cpu = ATOMIC_INIT(PANIC_CPU_INVALID);
- /*
- * A variant of panic() called from NMI context. We return if we've already
- * panicked on this CPU. If another CPU already panicked, loop in
- * nmi_panic_self_stop() which can provide architecture dependent code such
- * as saving register state for crash dump.
- */
- void nmi_panic(struct pt_regs *regs, const char *msg)
- {
- int old_cpu, cpu;
- cpu = raw_smp_processor_id();
- old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, cpu);
- if (old_cpu == PANIC_CPU_INVALID)
- panic("%s", msg);
- else if (old_cpu != cpu)
- nmi_panic_self_stop(regs);
- }
- EXPORT_SYMBOL(nmi_panic);
- static void panic_print_sys_info(bool console_flush)
- {
- if (console_flush) {
- if (panic_print & PANIC_PRINT_ALL_PRINTK_MSG)
- console_flush_on_panic(CONSOLE_REPLAY_ALL);
- return;
- }
- if (panic_print & PANIC_PRINT_TASK_INFO)
- show_state();
- if (panic_print & PANIC_PRINT_MEM_INFO)
- show_mem(0, NULL);
- if (panic_print & PANIC_PRINT_TIMER_INFO)
- sysrq_timer_list_show();
- if (panic_print & PANIC_PRINT_LOCK_INFO)
- debug_show_all_locks();
- if (panic_print & PANIC_PRINT_FTRACE_INFO)
- ftrace_dump(DUMP_ALL);
- }
- void check_panic_on_warn(const char *origin)
- {
- unsigned int limit;
- if (panic_on_warn)
- panic("%s: panic_on_warn set ...\n", origin);
- limit = READ_ONCE(warn_limit);
- if (atomic_inc_return(&warn_count) >= limit && limit)
- panic("%s: system warned too often (kernel.warn_limit is %d)",
- origin, limit);
- }
- /*
- * Helper that triggers the NMI backtrace (if set in panic_print)
- * and then performs the secondary CPUs shutdown - we cannot have
- * the NMI backtrace after the CPUs are off!
- */
- static void panic_other_cpus_shutdown(bool crash_kexec)
- {
- if (panic_print & PANIC_PRINT_ALL_CPU_BT)
- trigger_all_cpu_backtrace();
- /*
- * Note that smp_send_stop() is the usual SMP shutdown function,
- * which unfortunately may not be hardened to work in a panic
- * situation. If we want to do crash dump after notifier calls
- * and kmsg_dump, we will need architecture dependent extra
- * bits in addition to stopping other CPUs, hence we rely on
- * crash_smp_send_stop() for that.
- */
- if (!crash_kexec)
- smp_send_stop();
- else
- crash_smp_send_stop();
- }
- /**
- * panic - halt the system
- * @fmt: The text string to print
- *
- * Display a message, then perform cleanups.
- *
- * This function never returns.
- */
- void panic(const char *fmt, ...)
- {
- static char buf[1024];
- va_list args;
- long i, i_next = 0, len;
- int state = 0;
- int old_cpu, this_cpu;
- bool _crash_kexec_post_notifiers = crash_kexec_post_notifiers;
- if (panic_on_warn) {
- /*
- * This thread may hit another WARN() in the panic path.
- * Resetting this prevents additional WARN() from panicking the
- * system on this thread. Other threads are blocked by the
- * panic_mutex in panic().
- */
- panic_on_warn = 0;
- }
- /*
- * Disable local interrupts. This will prevent panic_smp_self_stop
- * from deadlocking the first cpu that invokes the panic, since
- * there is nothing to prevent an interrupt handler (that runs
- * after setting panic_cpu) from invoking panic() again.
- */
- local_irq_disable();
- preempt_disable_notrace();
- /*
- * It's possible to come here directly from a panic-assertion and
- * not have preempt disabled. Some functions called from here want
- * preempt to be disabled. No point enabling it later though...
- *
- * Only one CPU is allowed to execute the panic code from here. For
- * multiple parallel invocations of panic, all other CPUs either
- * stop themself or will wait until they are stopped by the 1st CPU
- * with smp_send_stop().
- *
- * `old_cpu == PANIC_CPU_INVALID' means this is the 1st CPU which
- * comes here, so go ahead.
- * `old_cpu == this_cpu' means we came from nmi_panic() which sets
- * panic_cpu to this CPU. In this case, this is also the 1st CPU.
- */
- this_cpu = raw_smp_processor_id();
- old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, this_cpu);
- if (old_cpu != PANIC_CPU_INVALID && old_cpu != this_cpu)
- panic_smp_self_stop();
- console_verbose();
- bust_spinlocks(1);
- va_start(args, fmt);
- len = vscnprintf(buf, sizeof(buf), fmt, args);
- va_end(args);
- if (len && buf[len - 1] == '\n')
- buf[len - 1] = '\0';
- pr_emerg("Kernel panic - not syncing: %s\n", buf);
- #ifdef CONFIG_DEBUG_BUGVERBOSE
- /*
- * Avoid nested stack-dumping if a panic occurs during oops processing
- */
- if (!test_taint(TAINT_DIE) && oops_in_progress <= 1)
- dump_stack();
- #endif
- /*
- * If kgdb is enabled, give it a chance to run before we stop all
- * the other CPUs or else we won't be able to debug processes left
- * running on them.
- */
- kgdb_panic(buf);
- /*
- * If we have crashed and we have a crash kernel loaded let it handle
- * everything else.
- * If we want to run this after calling panic_notifiers, pass
- * the "crash_kexec_post_notifiers" option to the kernel.
- *
- * Bypass the panic_cpu check and call __crash_kexec directly.
- */
- if (!_crash_kexec_post_notifiers)
- __crash_kexec(NULL);
- panic_other_cpus_shutdown(_crash_kexec_post_notifiers);
- /*
- * Run any panic handlers, including those that might need to
- * add information to the kmsg dump output.
- */
- atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
- panic_print_sys_info(false);
- kmsg_dump(KMSG_DUMP_PANIC);
- /*
- * If you doubt kdump always works fine in any situation,
- * "crash_kexec_post_notifiers" offers you a chance to run
- * panic_notifiers and dumping kmsg before kdump.
- * Note: since some panic_notifiers can make crashed kernel
- * more unstable, it can increase risks of the kdump failure too.
- *
- * Bypass the panic_cpu check and call __crash_kexec directly.
- */
- if (_crash_kexec_post_notifiers)
- __crash_kexec(NULL);
- console_unblank();
- /*
- * We may have ended up stopping the CPU holding the lock (in
- * smp_send_stop()) while still having some valuable data in the console
- * buffer. Try to acquire the lock then release it regardless of the
- * result. The release will also print the buffers out. Locks debug
- * should be disabled to avoid reporting bad unlock balance when
- * panic() is not being callled from OOPS.
- */
- debug_locks_off();
- console_flush_on_panic(CONSOLE_FLUSH_PENDING);
- panic_print_sys_info(true);
- if (!panic_blink)
- panic_blink = no_blink;
- if (panic_timeout > 0) {
- /*
- * Delay timeout seconds before rebooting the machine.
- * We can't use the "normal" timers since we just panicked.
- */
- pr_emerg("Rebooting in %d seconds..\n", panic_timeout);
- for (i = 0; i < panic_timeout * 1000; i += PANIC_TIMER_STEP) {
- touch_nmi_watchdog();
- if (i >= i_next) {
- i += panic_blink(state ^= 1);
- i_next = i + 3600 / PANIC_BLINK_SPD;
- }
- mdelay(PANIC_TIMER_STEP);
- }
- }
- if (panic_timeout != 0) {
- /*
- * This will not be a clean reboot, with everything
- * shutting down. But if there is a chance of
- * rebooting the system it will be rebooted.
- */
- if (panic_reboot_mode != REBOOT_UNDEFINED)
- reboot_mode = panic_reboot_mode;
- emergency_restart();
- }
- #ifdef __sparc__
- {
- extern int stop_a_enabled;
- /* Make sure the user can actually press Stop-A (L1-A) */
- stop_a_enabled = 1;
- pr_emerg("Press Stop-A (L1-A) from sun keyboard or send break\n"
- "twice on console to return to the boot prom\n");
- }
- #endif
- #if defined(CONFIG_S390)
- disabled_wait();
- #endif
- pr_emerg("---[ end Kernel panic - not syncing: %s ]---\n", buf);
- /* Do not scroll important messages printed above */
- suppress_printk = 1;
- local_irq_enable();
- for (i = 0; ; i += PANIC_TIMER_STEP) {
- touch_softlockup_watchdog();
- if (i >= i_next) {
- i += panic_blink(state ^= 1);
- i_next = i + 3600 / PANIC_BLINK_SPD;
- }
- mdelay(PANIC_TIMER_STEP);
- }
- }
- EXPORT_SYMBOL(panic);
- /*
- * TAINT_FORCED_RMMOD could be a per-module flag but the module
- * is being removed anyway.
- */
- const struct taint_flag taint_flags[TAINT_FLAGS_COUNT] = {
- [ TAINT_PROPRIETARY_MODULE ] = { 'P', 'G', true },
- [ TAINT_FORCED_MODULE ] = { 'F', ' ', true },
- [ TAINT_CPU_OUT_OF_SPEC ] = { 'S', ' ', false },
- [ TAINT_FORCED_RMMOD ] = { 'R', ' ', false },
- [ TAINT_MACHINE_CHECK ] = { 'M', ' ', false },
- [ TAINT_BAD_PAGE ] = { 'B', ' ', false },
- [ TAINT_USER ] = { 'U', ' ', false },
- [ TAINT_DIE ] = { 'D', ' ', false },
- [ TAINT_OVERRIDDEN_ACPI_TABLE ] = { 'A', ' ', false },
- [ TAINT_WARN ] = { 'W', ' ', false },
- [ TAINT_CRAP ] = { 'C', ' ', true },
- [ TAINT_FIRMWARE_WORKAROUND ] = { 'I', ' ', false },
- [ TAINT_OOT_MODULE ] = { 'O', ' ', true },
- [ TAINT_UNSIGNED_MODULE ] = { 'E', ' ', true },
- [ TAINT_SOFTLOCKUP ] = { 'L', ' ', false },
- [ TAINT_LIVEPATCH ] = { 'K', ' ', true },
- [ TAINT_AUX ] = { 'X', ' ', true },
- [ TAINT_RANDSTRUCT ] = { 'T', ' ', true },
- [ TAINT_TEST ] = { 'N', ' ', true },
- };
- /**
- * print_tainted - return a string to represent the kernel taint state.
- *
- * For individual taint flag meanings, see Documentation/admin-guide/sysctl/kernel.rst
- *
- * The string is overwritten by the next call to print_tainted(),
- * but is always NULL terminated.
- */
- const char *print_tainted(void)
- {
- static char buf[TAINT_FLAGS_COUNT + sizeof("Tainted: ")];
- BUILD_BUG_ON(ARRAY_SIZE(taint_flags) != TAINT_FLAGS_COUNT);
- if (tainted_mask) {
- char *s;
- int i;
- s = buf + sprintf(buf, "Tainted: ");
- for (i = 0; i < TAINT_FLAGS_COUNT; i++) {
- const struct taint_flag *t = &taint_flags[i];
- *s++ = test_bit(i, &tainted_mask) ?
- t->c_true : t->c_false;
- }
- *s = 0;
- } else
- snprintf(buf, sizeof(buf), "Not tainted");
- return buf;
- }
- int test_taint(unsigned flag)
- {
- return test_bit(flag, &tainted_mask);
- }
- EXPORT_SYMBOL(test_taint);
- unsigned long get_taint(void)
- {
- return tainted_mask;
- }
- /**
- * add_taint: add a taint flag if not already set.
- * @flag: one of the TAINT_* constants.
- * @lockdep_ok: whether lock debugging is still OK.
- *
- * If something bad has gone wrong, you'll want @lockdebug_ok = false, but for
- * some notewortht-but-not-corrupting cases, it can be set to true.
- */
- void add_taint(unsigned flag, enum lockdep_ok lockdep_ok)
- {
- if (lockdep_ok == LOCKDEP_NOW_UNRELIABLE && __debug_locks_off())
- pr_warn("Disabling lock debugging due to kernel taint\n");
- set_bit(flag, &tainted_mask);
- if (tainted_mask & panic_on_taint) {
- panic_on_taint = 0;
- panic("panic_on_taint set ...");
- }
- }
- EXPORT_SYMBOL(add_taint);
- static void spin_msec(int msecs)
- {
- int i;
- for (i = 0; i < msecs; i++) {
- touch_nmi_watchdog();
- mdelay(1);
- }
- }
- /*
- * It just happens that oops_enter() and oops_exit() are identically
- * implemented...
- */
- static void do_oops_enter_exit(void)
- {
- unsigned long flags;
- static int spin_counter;
- if (!pause_on_oops)
- return;
- spin_lock_irqsave(&pause_on_oops_lock, flags);
- if (pause_on_oops_flag == 0) {
- /* This CPU may now print the oops message */
- pause_on_oops_flag = 1;
- } else {
- /* We need to stall this CPU */
- if (!spin_counter) {
- /* This CPU gets to do the counting */
- spin_counter = pause_on_oops;
- do {
- spin_unlock(&pause_on_oops_lock);
- spin_msec(MSEC_PER_SEC);
- spin_lock(&pause_on_oops_lock);
- } while (--spin_counter);
- pause_on_oops_flag = 0;
- } else {
- /* This CPU waits for a different one */
- while (spin_counter) {
- spin_unlock(&pause_on_oops_lock);
- spin_msec(1);
- spin_lock(&pause_on_oops_lock);
- }
- }
- }
- spin_unlock_irqrestore(&pause_on_oops_lock, flags);
- }
- /*
- * Return true if the calling CPU is allowed to print oops-related info.
- * This is a bit racy..
- */
- bool oops_may_print(void)
- {
- return pause_on_oops_flag == 0;
- }
- /*
- * Called when the architecture enters its oops handler, before it prints
- * anything. If this is the first CPU to oops, and it's oopsing the first
- * time then let it proceed.
- *
- * This is all enabled by the pause_on_oops kernel boot option. We do all
- * this to ensure that oopses don't scroll off the screen. It has the
- * side-effect of preventing later-oopsing CPUs from mucking up the display,
- * too.
- *
- * It turns out that the CPU which is allowed to print ends up pausing for
- * the right duration, whereas all the other CPUs pause for twice as long:
- * once in oops_enter(), once in oops_exit().
- */
- void oops_enter(void)
- {
- tracing_off();
- /* can't trust the integrity of the kernel anymore: */
- debug_locks_off();
- do_oops_enter_exit();
- if (sysctl_oops_all_cpu_backtrace)
- trigger_all_cpu_backtrace();
- }
- static void print_oops_end_marker(void)
- {
- pr_warn("---[ end trace %016llx ]---\n", 0ULL);
- }
- /*
- * Called when the architecture exits its oops handler, after printing
- * everything.
- */
- void oops_exit(void)
- {
- do_oops_enter_exit();
- print_oops_end_marker();
- kmsg_dump(KMSG_DUMP_OOPS);
- }
- struct warn_args {
- const char *fmt;
- va_list args;
- };
- void __warn(const char *file, int line, void *caller, unsigned taint,
- struct pt_regs *regs, struct warn_args *args)
- {
- disable_trace_on_warning();
- if (file)
- pr_warn("WARNING: CPU: %d PID: %d at %s:%d %pS\n",
- raw_smp_processor_id(), current->pid, file, line,
- caller);
- else
- pr_warn("WARNING: CPU: %d PID: %d at %pS\n",
- raw_smp_processor_id(), current->pid, caller);
- if (args)
- vprintk(args->fmt, args->args);
- print_modules();
- if (regs)
- show_regs(regs);
- check_panic_on_warn("kernel");
- if (!regs)
- dump_stack();
- print_irqtrace_events(current);
- print_oops_end_marker();
- trace_error_report_end(ERROR_DETECTOR_WARN, (unsigned long)caller);
- /* Just a warning, don't kill lockdep. */
- add_taint(taint, LOCKDEP_STILL_OK);
- }
- #ifndef __WARN_FLAGS
- void warn_slowpath_fmt(const char *file, int line, unsigned taint,
- const char *fmt, ...)
- {
- bool rcu = warn_rcu_enter();
- struct warn_args args;
- pr_warn(CUT_HERE);
- if (!fmt) {
- __warn(file, line, __builtin_return_address(0), taint,
- NULL, NULL);
- warn_rcu_exit(rcu);
- return;
- }
- args.fmt = fmt;
- va_start(args.args, fmt);
- __warn(file, line, __builtin_return_address(0), taint, NULL, &args);
- va_end(args.args);
- warn_rcu_exit(rcu);
- }
- EXPORT_SYMBOL(warn_slowpath_fmt);
- #else
- void __warn_printk(const char *fmt, ...)
- {
- bool rcu = warn_rcu_enter();
- va_list args;
- pr_warn(CUT_HERE);
- va_start(args, fmt);
- vprintk(fmt, args);
- va_end(args);
- warn_rcu_exit(rcu);
- }
- EXPORT_SYMBOL(__warn_printk);
- #endif
- #ifdef CONFIG_BUG
- /* Support resetting WARN*_ONCE state */
- static int clear_warn_once_set(void *data, u64 val)
- {
- generic_bug_clear_once();
- memset(__start_once, 0, __end_once - __start_once);
- return 0;
- }
- DEFINE_DEBUGFS_ATTRIBUTE(clear_warn_once_fops, NULL, clear_warn_once_set,
- "%lld\n");
- static __init int register_warn_debugfs(void)
- {
- /* Don't care about failure */
- debugfs_create_file_unsafe("clear_warn_once", 0200, NULL, NULL,
- &clear_warn_once_fops);
- return 0;
- }
- device_initcall(register_warn_debugfs);
- #endif
- #ifdef CONFIG_STACKPROTECTOR
- /*
- * Called when gcc's -fstack-protector feature is used, and
- * gcc detects corruption of the on-stack canary value
- */
- __visible noinstr void __stack_chk_fail(void)
- {
- instrumentation_begin();
- panic("stack-protector: Kernel stack is corrupted in: %pB",
- __builtin_return_address(0));
- instrumentation_end();
- }
- EXPORT_SYMBOL(__stack_chk_fail);
- #endif
- core_param(panic, panic_timeout, int, 0644);
- core_param(panic_print, panic_print, ulong, 0644);
- core_param(pause_on_oops, pause_on_oops, int, 0644);
- core_param(panic_on_warn, panic_on_warn, int, 0644);
- core_param(crash_kexec_post_notifiers, crash_kexec_post_notifiers, bool, 0644);
- static int __init oops_setup(char *s)
- {
- if (!s)
- return -EINVAL;
- if (!strcmp(s, "panic"))
- panic_on_oops = 1;
- return 0;
- }
- early_param("oops", oops_setup);
- static int __init panic_on_taint_setup(char *s)
- {
- char *taint_str;
- if (!s)
- return -EINVAL;
- taint_str = strsep(&s, ",");
- if (kstrtoul(taint_str, 16, &panic_on_taint))
- return -EINVAL;
- /* make sure panic_on_taint doesn't hold out-of-range TAINT flags */
- panic_on_taint &= TAINT_FLAGS_MAX;
- if (!panic_on_taint)
- return -EINVAL;
- if (s && !strcmp(s, "nousertaint"))
- panic_on_taint_nousertaint = true;
- pr_info("panic_on_taint: bitmask=0x%lx nousertaint_mode=%sabled\n",
- panic_on_taint, panic_on_taint_nousertaint ? "en" : "dis");
- return 0;
- }
- early_param("panic_on_taint", panic_on_taint_setup);
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