diff options
Diffstat (limited to 'kernel/panic.c')
| -rw-r--r-- | kernel/panic.c | 150 |
1 files changed, 107 insertions, 43 deletions
diff --git a/kernel/panic.c b/kernel/panic.c index b69ee9e76cb2..da323209f583 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -23,6 +23,7 @@ #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> @@ -31,19 +32,32 @@ #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_GCC_PLUGIN_RANDSTRUCT) ? (1 << TAINT_RANDSTRUCT) : 0; + 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); @@ -54,12 +68,35 @@ EXPORT_SYMBOL_GPL(panic_timeout); #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; @@ -135,10 +172,16 @@ void nmi_panic(struct pt_regs *regs, const char *msg) } EXPORT_SYMBOL(nmi_panic); -static void panic_print_sys_info(void) +static void panic_print_sys_info(bool console_flush) { - if (panic_print & PANIC_PRINT_ALL_PRINTK_MSG) - console_flush_on_panic(CONSOLE_REPLAY_ALL); + 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(); @@ -173,6 +216,16 @@ void panic(const char *fmt, ...) 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 @@ -237,7 +290,6 @@ void panic(const char *fmt, ...) * Bypass the panic_cpu check and call __crash_kexec directly. */ if (!_crash_kexec_post_notifiers) { - printk_safe_flush_on_panic(); __crash_kexec(NULL); /* @@ -261,8 +313,8 @@ void panic(const char *fmt, ...) */ atomic_notifier_call_chain(&panic_notifier_list, 0, buf); - /* Call flush even twice. It tries harder with a single online CPU */ - printk_safe_flush_on_panic(); + panic_print_sys_info(false); + kmsg_dump(KMSG_DUMP_PANIC); /* @@ -277,9 +329,6 @@ void panic(const char *fmt, ...) if (_crash_kexec_post_notifiers) __crash_kexec(NULL); -#ifdef CONFIG_VT - unblank_screen(); -#endif console_unblank(); /* @@ -293,7 +342,7 @@ void panic(const char *fmt, ...) debug_locks_off(); console_flush_on_panic(CONSOLE_FLUSH_PENDING); - panic_print_sys_info(); + panic_print_sys_info(true); if (!panic_blink) panic_blink = no_blink; @@ -376,6 +425,7 @@ const struct taint_flag taint_flags[TAINT_FLAGS_COUNT] = { [ TAINT_LIVEPATCH ] = { 'K', ' ', true }, [ TAINT_AUX ] = { 'X', ' ', true }, [ TAINT_RANDSTRUCT ] = { 'T', ' ', true }, + [ TAINT_TEST ] = { 'N', ' ', true }, }; /** @@ -434,6 +484,11 @@ void add_taint(unsigned flag, enum lockdep_ok lockdep_ok) 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); @@ -490,7 +545,7 @@ static void do_oops_enter_exit(void) * Return true if the calling CPU is allowed to print oops-related info. * This is a bit racy.. */ -int oops_may_print(void) +bool oops_may_print(void) { return pause_on_oops_flag == 0; } @@ -515,28 +570,14 @@ void oops_enter(void) /* can't trust the integrity of the kernel anymore: */ debug_locks_off(); do_oops_enter_exit(); -} -/* - * 64-bit random ID for oopses: - */ -static u64 oops_id; - -static int init_oops_id(void) -{ - if (!oops_id) - get_random_bytes(&oops_id, sizeof(oops_id)); - else - oops_id++; - - return 0; + if (sysctl_oops_all_cpu_backtrace) + trigger_all_cpu_backtrace(); } -late_initcall(init_oops_id); -void print_oops_end_marker(void) +static void print_oops_end_marker(void) { - init_oops_id(); - pr_warn("---[ end trace %016llx ]---\n", (unsigned long long)oops_id); + pr_warn("---[ end trace %016llx ]---\n", 0ULL); } /* @@ -571,27 +612,21 @@ void __warn(const char *file, int line, void *caller, unsigned taint, if (args) vprintk(args->fmt, args->args); - 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; - panic("panic_on_warn set ...\n"); - } - print_modules(); if (regs) show_regs(regs); - else + + if (panic_on_warn) + panic("panic_on_warn set ...\n"); + + 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); @@ -662,10 +697,12 @@ device_initcall(register_warn_debugfs); * Called when gcc's -fstack-protector feature is used, and * gcc detects corruption of the on-stack canary value */ -__visible void __stack_chk_fail(void) +__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); @@ -686,3 +723,30 @@ static int __init oops_setup(char *s) 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); |