// 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 <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; 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 0x00000040unsigned long panic_print; ATOMIC_NOTIFIER_HEAD(panic_notifier_list); EXPORT_SYMBOL(panic_notifier_list); #if defined(CONFIG_SMP) && defined(CONFIG_SYSCTL)static struct ctl_table kern_panic_table[] = { { .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, }, { }}; 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 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_ALL_CPU_BT) trigger_all_cpu_backtrace(); 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);} /** * 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); /* * 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(); } else { /* * If we want to do crash dump after notifier calls and * kmsg_dump, we will need architecture dependent extra * works in addition to stopping other CPUs. */ crash_smp_send_stop(); } /* * 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();Lines 1–500 of 752. 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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 <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; 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); #if defined(CONFIG_SMP) && defined(CONFIG_SYSCTL) static struct ctl_table kern_panic_table[] = { { .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, }, { } }; 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 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_ALL_CPU_BT) trigger_all_cpu_backtrace(); 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); } /** * 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); /* * 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(); } else { /* * If we want to do crash dump after notifier calls and * kmsg_dump, we will need architecture dependent extra * works in addition to stopping other CPUs. */ crash_smp_send_stop(); } /* * 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();