diff options
Diffstat (limited to 'kernel/panic.c')
| -rw-r--r-- | kernel/panic.c | 149 |
1 files changed, 105 insertions, 44 deletions
diff --git a/kernel/panic.c b/kernel/panic.c index b0b9a8bf4560..72fcbb5a071b 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -36,6 +36,7 @@ #include <linux/sysfs.h> #include <linux/context_tracking.h> #include <linux/seq_buf.h> +#include <linux/sys_info.h> #include <trace/events/error_report.h> #include <asm/sections.h> @@ -63,20 +64,13 @@ int panic_on_warn __read_mostly; unsigned long panic_on_taint; bool panic_on_taint_nousertaint = false; static unsigned int warn_limit __read_mostly; +static bool panic_console_replay; bool panic_triggering_all_cpu_backtrace; 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 -#define PANIC_PRINT_BLOCKED_TASKS 0x00000080 unsigned long panic_print; ATOMIC_NOTIFIER_HEAD(panic_notifier_list); @@ -84,6 +78,57 @@ ATOMIC_NOTIFIER_HEAD(panic_notifier_list); EXPORT_SYMBOL(panic_notifier_list); #ifdef CONFIG_SYSCTL + +/* + * Taint values can only be increased + * This means we can safely use a temporary. + */ +static int proc_taint(const struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + struct ctl_table t; + unsigned long tmptaint = get_taint(); + int err; + + if (write && !capable(CAP_SYS_ADMIN)) + return -EPERM; + + t = *table; + t.data = &tmptaint; + err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos); + if (err < 0) + return err; + + if (write) { + int i; + + /* + * If we are relying on panic_on_taint not producing + * false positives due to userspace input, bail out + * before setting the requested taint flags. + */ + if (panic_on_taint_nousertaint && (tmptaint & panic_on_taint)) + return -EINVAL; + + /* + * Poor man's atomic or. Not worth adding a primitive + * to everyone's atomic.h for this + */ + for (i = 0; i < TAINT_FLAGS_COUNT; i++) + if ((1UL << i) & tmptaint) + add_taint(i, LOCKDEP_STILL_OK); + } + + return err; +} + +static int sysctl_panic_print_handler(const struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + pr_info_once("Kernel: 'panic_print' sysctl interface will be obsoleted by both 'panic_sys_info' and 'panic_console_replay'\n"); + return proc_doulongvec_minmax(table, write, buffer, lenp, ppos); +} + static const struct ctl_table kern_panic_table[] = { #ifdef CONFIG_SMP { @@ -97,6 +142,12 @@ static const struct ctl_table kern_panic_table[] = { }, #endif { + .procname = "tainted", + .maxlen = sizeof(long), + .mode = 0644, + .proc_handler = proc_taint, + }, + { .procname = "panic", .data = &panic_timeout, .maxlen = sizeof(int), @@ -115,7 +166,7 @@ static const struct ctl_table kern_panic_table[] = { .data = &panic_print, .maxlen = sizeof(unsigned long), .mode = 0644, - .proc_handler = proc_doulongvec_minmax, + .proc_handler = sysctl_panic_print_handler, }, { .procname = "panic_on_warn", @@ -133,6 +184,23 @@ static const struct ctl_table kern_panic_table[] = { .mode = 0644, .proc_handler = proc_douintvec, }, +#if (defined(CONFIG_X86_32) || defined(CONFIG_PARISC)) && \ + defined(CONFIG_DEBUG_STACKOVERFLOW) + { + .procname = "panic_on_stackoverflow", + .data = &sysctl_panic_on_stackoverflow, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, +#endif + { + .procname = "panic_sys_info", + .data = &panic_print, + .maxlen = sizeof(panic_print), + .mode = 0644, + .proc_handler = sysctl_sys_info_handler, + }, }; static __init int kernel_panic_sysctls_init(void) @@ -143,6 +211,15 @@ static __init int kernel_panic_sysctls_init(void) late_initcall(kernel_panic_sysctls_init); #endif +/* The format is "panic_sys_info=tasks,mem,locks,ftrace,..." */ +static int __init setup_panic_sys_info(char *buf) +{ + /* There is no risk of race in kernel boot phase */ + panic_print = sys_info_parse_param(buf); + return 1; +} +__setup("panic_sys_info=", setup_panic_sys_info); + static atomic_t warn_count = ATOMIC_INIT(0); #ifdef CONFIG_SYSFS @@ -238,33 +315,6 @@ void nmi_panic(struct pt_regs *regs, const char *msg) } 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(); - - 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); - - if (panic_print & PANIC_PRINT_BLOCKED_TASKS) - show_state_filter(TASK_UNINTERRUPTIBLE); -} - void check_panic_on_warn(const char *origin) { unsigned int limit; @@ -285,7 +335,7 @@ void check_panic_on_warn(const char *origin) */ static void panic_other_cpus_shutdown(bool crash_kexec) { - if (panic_print & PANIC_PRINT_ALL_CPU_BT) { + if (panic_print & SYS_INFO_ALL_CPU_BT) { /* Temporary allow non-panic CPUs to write their backtraces. */ panic_triggering_all_cpu_backtrace = true; trigger_all_cpu_backtrace(); @@ -307,15 +357,15 @@ static void panic_other_cpus_shutdown(bool crash_kexec) } /** - * panic - halt the system + * vpanic - halt the system * @fmt: The text string to print + * @args: Arguments for the format string * * Display a message, then perform cleanups. This function never returns. */ -void panic(const char *fmt, ...) +void vpanic(const char *fmt, va_list args) { static char buf[1024]; - va_list args; long i, i_next = 0, len; int state = 0; int old_cpu, this_cpu; @@ -366,9 +416,7 @@ void panic(const char *fmt, ...) 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'; @@ -410,7 +458,7 @@ void panic(const char *fmt, ...) */ atomic_notifier_call_chain(&panic_notifier_list, 0, buf); - panic_print_sys_info(false); + sys_info(panic_print); kmsg_dump_desc(KMSG_DUMP_PANIC, buf); @@ -439,7 +487,9 @@ void panic(const char *fmt, ...) debug_locks_off(); console_flush_on_panic(CONSOLE_FLUSH_PENDING); - panic_print_sys_info(true); + if ((panic_print & SYS_INFO_PANIC_CONSOLE_REPLAY) || + panic_console_replay) + console_flush_on_panic(CONSOLE_REPLAY_ALL); if (!panic_blink) panic_blink = no_blink; @@ -505,7 +555,17 @@ void panic(const char *fmt, ...) mdelay(PANIC_TIMER_STEP); } } +EXPORT_SYMBOL(vpanic); +/* Identical to vpanic(), except it takes variadic arguments instead of va_list */ +void panic(const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + vpanic(fmt, args); + va_end(args); +} EXPORT_SYMBOL(panic); #define TAINT_FLAG(taint, _c_true, _c_false, _module) \ @@ -881,6 +941,7 @@ 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); +core_param(panic_console_replay, panic_console_replay, bool, 0644); static int __init oops_setup(char *s) { |