1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/kernel/panic.c 4 * 5 * Copyright (C) 1991, 1992 Linus Torvalds 6 */ 7 8 /* 9 * This function is used through-out the kernel (including mm and fs) 10 * to indicate a major problem. 11 */ 12 #include <linux/debug_locks.h> 13 #include <linux/sched/debug.h> 14 #include <linux/interrupt.h> 15 #include <linux/kgdb.h> 16 #include <linux/kmsg_dump.h> 17 #include <linux/kallsyms.h> 18 #include <linux/notifier.h> 19 #include <linux/vt_kern.h> 20 #include <linux/module.h> 21 #include <linux/random.h> 22 #include <linux/ftrace.h> 23 #include <linux/reboot.h> 24 #include <linux/delay.h> 25 #include <linux/kexec.h> 26 #include <linux/panic_notifier.h> 27 #include <linux/sched.h> 28 #include <linux/sysrq.h> 29 #include <linux/init.h> 30 #include <linux/nmi.h> 31 #include <linux/console.h> 32 #include <linux/bug.h> 33 #include <linux/ratelimit.h> 34 #include <linux/debugfs.h> 35 #include <trace/events/error_report.h> 36 #include <asm/sections.h> 37 38 #define PANIC_TIMER_STEP 100 39 #define PANIC_BLINK_SPD 18 40 41 #ifdef CONFIG_SMP 42 /* 43 * Should we dump all CPUs backtraces in an oops event? 44 * Defaults to 0, can be changed via sysctl. 45 */ 46 static unsigned int __read_mostly sysctl_oops_all_cpu_backtrace; 47 #else 48 #define sysctl_oops_all_cpu_backtrace 0 49 #endif /* CONFIG_SMP */ 50 51 int panic_on_oops = CONFIG_PANIC_ON_OOPS_VALUE; 52 static unsigned long tainted_mask = 53 IS_ENABLED(CONFIG_RANDSTRUCT) ? (1 << TAINT_RANDSTRUCT) : 0; 54 static int pause_on_oops; 55 static int pause_on_oops_flag; 56 static DEFINE_SPINLOCK(pause_on_oops_lock); 57 bool crash_kexec_post_notifiers; 58 int panic_on_warn __read_mostly; 59 unsigned long panic_on_taint; 60 bool panic_on_taint_nousertaint = false; 61 62 int panic_timeout = CONFIG_PANIC_TIMEOUT; 63 EXPORT_SYMBOL_GPL(panic_timeout); 64 65 #define PANIC_PRINT_TASK_INFO 0x00000001 66 #define PANIC_PRINT_MEM_INFO 0x00000002 67 #define PANIC_PRINT_TIMER_INFO 0x00000004 68 #define PANIC_PRINT_LOCK_INFO 0x00000008 69 #define PANIC_PRINT_FTRACE_INFO 0x00000010 70 #define PANIC_PRINT_ALL_PRINTK_MSG 0x00000020 71 #define PANIC_PRINT_ALL_CPU_BT 0x00000040 72 unsigned long panic_print; 73 74 ATOMIC_NOTIFIER_HEAD(panic_notifier_list); 75 76 EXPORT_SYMBOL(panic_notifier_list); 77 78 #if defined(CONFIG_SMP) && defined(CONFIG_SYSCTL) 79 static struct ctl_table kern_panic_table[] = { 80 { 81 .procname = "oops_all_cpu_backtrace", 82 .data = &sysctl_oops_all_cpu_backtrace, 83 .maxlen = sizeof(int), 84 .mode = 0644, 85 .proc_handler = proc_dointvec_minmax, 86 .extra1 = SYSCTL_ZERO, 87 .extra2 = SYSCTL_ONE, 88 }, 89 { } 90 }; 91 92 static __init int kernel_panic_sysctls_init(void) 93 { 94 register_sysctl_init("kernel", kern_panic_table); 95 return 0; 96 } 97 late_initcall(kernel_panic_sysctls_init); 98 #endif 99 100 static long no_blink(int state) 101 { 102 return 0; 103 } 104 105 /* Returns how long it waited in ms */ 106 long (*panic_blink)(int state); 107 EXPORT_SYMBOL(panic_blink); 108 109 /* 110 * Stop ourself in panic -- architecture code may override this 111 */ 112 void __weak panic_smp_self_stop(void) 113 { 114 while (1) 115 cpu_relax(); 116 } 117 118 /* 119 * Stop ourselves in NMI context if another CPU has already panicked. Arch code 120 * may override this to prepare for crash dumping, e.g. save regs info. 121 */ 122 void __weak nmi_panic_self_stop(struct pt_regs *regs) 123 { 124 panic_smp_self_stop(); 125 } 126 127 /* 128 * Stop other CPUs in panic. Architecture dependent code may override this 129 * with more suitable version. For example, if the architecture supports 130 * crash dump, it should save registers of each stopped CPU and disable 131 * per-CPU features such as virtualization extensions. 132 */ 133 void __weak crash_smp_send_stop(void) 134 { 135 static int cpus_stopped; 136 137 /* 138 * This function can be called twice in panic path, but obviously 139 * we execute this only once. 140 */ 141 if (cpus_stopped) 142 return; 143 144 /* 145 * Note smp_send_stop is the usual smp shutdown function, which 146 * unfortunately means it may not be hardened to work in a panic 147 * situation. 148 */ 149 smp_send_stop(); 150 cpus_stopped = 1; 151 } 152 153 atomic_t panic_cpu = ATOMIC_INIT(PANIC_CPU_INVALID); 154 155 /* 156 * A variant of panic() called from NMI context. We return if we've already 157 * panicked on this CPU. If another CPU already panicked, loop in 158 * nmi_panic_self_stop() which can provide architecture dependent code such 159 * as saving register state for crash dump. 160 */ 161 void nmi_panic(struct pt_regs *regs, const char *msg) 162 { 163 int old_cpu, cpu; 164 165 cpu = raw_smp_processor_id(); 166 old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, cpu); 167 168 if (old_cpu == PANIC_CPU_INVALID) 169 panic("%s", msg); 170 else if (old_cpu != cpu) 171 nmi_panic_self_stop(regs); 172 } 173 EXPORT_SYMBOL(nmi_panic); 174 175 static void panic_print_sys_info(bool console_flush) 176 { 177 if (console_flush) { 178 if (panic_print & PANIC_PRINT_ALL_PRINTK_MSG) 179 console_flush_on_panic(CONSOLE_REPLAY_ALL); 180 return; 181 } 182 183 if (panic_print & PANIC_PRINT_ALL_CPU_BT) 184 trigger_all_cpu_backtrace(); 185 186 if (panic_print & PANIC_PRINT_TASK_INFO) 187 show_state(); 188 189 if (panic_print & PANIC_PRINT_MEM_INFO) 190 show_mem(0, NULL); 191 192 if (panic_print & PANIC_PRINT_TIMER_INFO) 193 sysrq_timer_list_show(); 194 195 if (panic_print & PANIC_PRINT_LOCK_INFO) 196 debug_show_all_locks(); 197 198 if (panic_print & PANIC_PRINT_FTRACE_INFO) 199 ftrace_dump(DUMP_ALL); 200 } 201 202 /** 203 * panic - halt the system 204 * @fmt: The text string to print 205 * 206 * Display a message, then perform cleanups. 207 * 208 * This function never returns. 209 */ 210 void panic(const char *fmt, ...) 211 { 212 static char buf[1024]; 213 va_list args; 214 long i, i_next = 0, len; 215 int state = 0; 216 int old_cpu, this_cpu; 217 bool _crash_kexec_post_notifiers = crash_kexec_post_notifiers; 218 219 if (panic_on_warn) { 220 /* 221 * This thread may hit another WARN() in the panic path. 222 * Resetting this prevents additional WARN() from panicking the 223 * system on this thread. Other threads are blocked by the 224 * panic_mutex in panic(). 225 */ 226 panic_on_warn = 0; 227 } 228 229 /* 230 * Disable local interrupts. This will prevent panic_smp_self_stop 231 * from deadlocking the first cpu that invokes the panic, since 232 * there is nothing to prevent an interrupt handler (that runs 233 * after setting panic_cpu) from invoking panic() again. 234 */ 235 local_irq_disable(); 236 preempt_disable_notrace(); 237 238 /* 239 * It's possible to come here directly from a panic-assertion and 240 * not have preempt disabled. Some functions called from here want 241 * preempt to be disabled. No point enabling it later though... 242 * 243 * Only one CPU is allowed to execute the panic code from here. For 244 * multiple parallel invocations of panic, all other CPUs either 245 * stop themself or will wait until they are stopped by the 1st CPU 246 * with smp_send_stop(). 247 * 248 * `old_cpu == PANIC_CPU_INVALID' means this is the 1st CPU which 249 * comes here, so go ahead. 250 * `old_cpu == this_cpu' means we came from nmi_panic() which sets 251 * panic_cpu to this CPU. In this case, this is also the 1st CPU. 252 */ 253 this_cpu = raw_smp_processor_id(); 254 old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, this_cpu); 255 256 if (old_cpu != PANIC_CPU_INVALID && old_cpu != this_cpu) 257 panic_smp_self_stop(); 258 259 console_verbose(); 260 bust_spinlocks(1); 261 va_start(args, fmt); 262 len = vscnprintf(buf, sizeof(buf), fmt, args); 263 va_end(args); 264 265 if (len && buf[len - 1] == '\n') 266 buf[len - 1] = '\0'; 267 268 pr_emerg("Kernel panic - not syncing: %s\n", buf); 269 #ifdef CONFIG_DEBUG_BUGVERBOSE 270 /* 271 * Avoid nested stack-dumping if a panic occurs during oops processing 272 */ 273 if (!test_taint(TAINT_DIE) && oops_in_progress <= 1) 274 dump_stack(); 275 #endif 276 277 /* 278 * If kgdb is enabled, give it a chance to run before we stop all 279 * the other CPUs or else we won't be able to debug processes left 280 * running on them. 281 */ 282 kgdb_panic(buf); 283 284 /* 285 * If we have crashed and we have a crash kernel loaded let it handle 286 * everything else. 287 * If we want to run this after calling panic_notifiers, pass 288 * the "crash_kexec_post_notifiers" option to the kernel. 289 * 290 * Bypass the panic_cpu check and call __crash_kexec directly. 291 */ 292 if (!_crash_kexec_post_notifiers) { 293 __crash_kexec(NULL); 294 295 /* 296 * Note smp_send_stop is the usual smp shutdown function, which 297 * unfortunately means it may not be hardened to work in a 298 * panic situation. 299 */ 300 smp_send_stop(); 301 } else { 302 /* 303 * If we want to do crash dump after notifier calls and 304 * kmsg_dump, we will need architecture dependent extra 305 * works in addition to stopping other CPUs. 306 */ 307 crash_smp_send_stop(); 308 } 309 310 /* 311 * Run any panic handlers, including those that might need to 312 * add information to the kmsg dump output. 313 */ 314 atomic_notifier_call_chain(&panic_notifier_list, 0, buf); 315 316 panic_print_sys_info(false); 317 318 kmsg_dump(KMSG_DUMP_PANIC); 319 320 /* 321 * If you doubt kdump always works fine in any situation, 322 * "crash_kexec_post_notifiers" offers you a chance to run 323 * panic_notifiers and dumping kmsg before kdump. 324 * Note: since some panic_notifiers can make crashed kernel 325 * more unstable, it can increase risks of the kdump failure too. 326 * 327 * Bypass the panic_cpu check and call __crash_kexec directly. 328 */ 329 if (_crash_kexec_post_notifiers) 330 __crash_kexec(NULL); 331 332 #ifdef CONFIG_VT 333 unblank_screen(); 334 #endif 335 console_unblank(); 336 337 /* 338 * We may have ended up stopping the CPU holding the lock (in 339 * smp_send_stop()) while still having some valuable data in the console 340 * buffer. Try to acquire the lock then release it regardless of the 341 * result. The release will also print the buffers out. Locks debug 342 * should be disabled to avoid reporting bad unlock balance when 343 * panic() is not being callled from OOPS. 344 */ 345 debug_locks_off(); 346 console_flush_on_panic(CONSOLE_FLUSH_PENDING); 347 348 panic_print_sys_info(true); 349 350 if (!panic_blink) 351 panic_blink = no_blink; 352 353 if (panic_timeout > 0) { 354 /* 355 * Delay timeout seconds before rebooting the machine. 356 * We can't use the "normal" timers since we just panicked. 357 */ 358 pr_emerg("Rebooting in %d seconds..\n", panic_timeout); 359 360 for (i = 0; i < panic_timeout * 1000; i += PANIC_TIMER_STEP) { 361 touch_nmi_watchdog(); 362 if (i >= i_next) { 363 i += panic_blink(state ^= 1); 364 i_next = i + 3600 / PANIC_BLINK_SPD; 365 } 366 mdelay(PANIC_TIMER_STEP); 367 } 368 } 369 if (panic_timeout != 0) { 370 /* 371 * This will not be a clean reboot, with everything 372 * shutting down. But if there is a chance of 373 * rebooting the system it will be rebooted. 374 */ 375 if (panic_reboot_mode != REBOOT_UNDEFINED) 376 reboot_mode = panic_reboot_mode; 377 emergency_restart(); 378 } 379 #ifdef __sparc__ 380 { 381 extern int stop_a_enabled; 382 /* Make sure the user can actually press Stop-A (L1-A) */ 383 stop_a_enabled = 1; 384 pr_emerg("Press Stop-A (L1-A) from sun keyboard or send break\n" 385 "twice on console to return to the boot prom\n"); 386 } 387 #endif 388 #if defined(CONFIG_S390) 389 disabled_wait(); 390 #endif 391 pr_emerg("---[ end Kernel panic - not syncing: %s ]---\n", buf); 392 393 /* Do not scroll important messages printed above */ 394 suppress_printk = 1; 395 local_irq_enable(); 396 for (i = 0; ; i += PANIC_TIMER_STEP) { 397 touch_softlockup_watchdog(); 398 if (i >= i_next) { 399 i += panic_blink(state ^= 1); 400 i_next = i + 3600 / PANIC_BLINK_SPD; 401 } 402 mdelay(PANIC_TIMER_STEP); 403 } 404 } 405 406 EXPORT_SYMBOL(panic); 407 408 /* 409 * TAINT_FORCED_RMMOD could be a per-module flag but the module 410 * is being removed anyway. 411 */ 412 const struct taint_flag taint_flags[TAINT_FLAGS_COUNT] = { 413 [ TAINT_PROPRIETARY_MODULE ] = { 'P', 'G', true }, 414 [ TAINT_FORCED_MODULE ] = { 'F', ' ', true }, 415 [ TAINT_CPU_OUT_OF_SPEC ] = { 'S', ' ', false }, 416 [ TAINT_FORCED_RMMOD ] = { 'R', ' ', false }, 417 [ TAINT_MACHINE_CHECK ] = { 'M', ' ', false }, 418 [ TAINT_BAD_PAGE ] = { 'B', ' ', false }, 419 [ TAINT_USER ] = { 'U', ' ', false }, 420 [ TAINT_DIE ] = { 'D', ' ', false }, 421 [ TAINT_OVERRIDDEN_ACPI_TABLE ] = { 'A', ' ', false }, 422 [ TAINT_WARN ] = { 'W', ' ', false }, 423 [ TAINT_CRAP ] = { 'C', ' ', true }, 424 [ TAINT_FIRMWARE_WORKAROUND ] = { 'I', ' ', false }, 425 [ TAINT_OOT_MODULE ] = { 'O', ' ', true }, 426 [ TAINT_UNSIGNED_MODULE ] = { 'E', ' ', true }, 427 [ TAINT_SOFTLOCKUP ] = { 'L', ' ', false }, 428 [ TAINT_LIVEPATCH ] = { 'K', ' ', true }, 429 [ TAINT_AUX ] = { 'X', ' ', true }, 430 [ TAINT_RANDSTRUCT ] = { 'T', ' ', true }, 431 [ TAINT_TEST ] = { 'N', ' ', true }, 432 }; 433 434 /** 435 * print_tainted - return a string to represent the kernel taint state. 436 * 437 * For individual taint flag meanings, see Documentation/admin-guide/sysctl/kernel.rst 438 * 439 * The string is overwritten by the next call to print_tainted(), 440 * but is always NULL terminated. 441 */ 442 const char *print_tainted(void) 443 { 444 static char buf[TAINT_FLAGS_COUNT + sizeof("Tainted: ")]; 445 446 BUILD_BUG_ON(ARRAY_SIZE(taint_flags) != TAINT_FLAGS_COUNT); 447 448 if (tainted_mask) { 449 char *s; 450 int i; 451 452 s = buf + sprintf(buf, "Tainted: "); 453 for (i = 0; i < TAINT_FLAGS_COUNT; i++) { 454 const struct taint_flag *t = &taint_flags[i]; 455 *s++ = test_bit(i, &tainted_mask) ? 456 t->c_true : t->c_false; 457 } 458 *s = 0; 459 } else 460 snprintf(buf, sizeof(buf), "Not tainted"); 461 462 return buf; 463 } 464 465 int test_taint(unsigned flag) 466 { 467 return test_bit(flag, &tainted_mask); 468 } 469 EXPORT_SYMBOL(test_taint); 470 471 unsigned long get_taint(void) 472 { 473 return tainted_mask; 474 } 475 476 /** 477 * add_taint: add a taint flag if not already set. 478 * @flag: one of the TAINT_* constants. 479 * @lockdep_ok: whether lock debugging is still OK. 480 * 481 * If something bad has gone wrong, you'll want @lockdebug_ok = false, but for 482 * some notewortht-but-not-corrupting cases, it can be set to true. 483 */ 484 void add_taint(unsigned flag, enum lockdep_ok lockdep_ok) 485 { 486 if (lockdep_ok == LOCKDEP_NOW_UNRELIABLE && __debug_locks_off()) 487 pr_warn("Disabling lock debugging due to kernel taint\n"); 488 489 set_bit(flag, &tainted_mask); 490 491 if (tainted_mask & panic_on_taint) { 492 panic_on_taint = 0; 493 panic("panic_on_taint set ..."); 494 } 495 } 496 EXPORT_SYMBOL(add_taint); 497 498 static void spin_msec(int msecs) 499 { 500 int i; 501 502 for (i = 0; i < msecs; i++) { 503 touch_nmi_watchdog(); 504 mdelay(1); 505 } 506 } 507 508 /* 509 * It just happens that oops_enter() and oops_exit() are identically 510 * implemented... 511 */ 512 static void do_oops_enter_exit(void) 513 { 514 unsigned long flags; 515 static int spin_counter; 516 517 if (!pause_on_oops) 518 return; 519 520 spin_lock_irqsave(&pause_on_oops_lock, flags); 521 if (pause_on_oops_flag == 0) { 522 /* This CPU may now print the oops message */ 523 pause_on_oops_flag = 1; 524 } else { 525 /* We need to stall this CPU */ 526 if (!spin_counter) { 527 /* This CPU gets to do the counting */ 528 spin_counter = pause_on_oops; 529 do { 530 spin_unlock(&pause_on_oops_lock); 531 spin_msec(MSEC_PER_SEC); 532 spin_lock(&pause_on_oops_lock); 533 } while (--spin_counter); 534 pause_on_oops_flag = 0; 535 } else { 536 /* This CPU waits for a different one */ 537 while (spin_counter) { 538 spin_unlock(&pause_on_oops_lock); 539 spin_msec(1); 540 spin_lock(&pause_on_oops_lock); 541 } 542 } 543 } 544 spin_unlock_irqrestore(&pause_on_oops_lock, flags); 545 } 546 547 /* 548 * Return true if the calling CPU is allowed to print oops-related info. 549 * This is a bit racy.. 550 */ 551 bool oops_may_print(void) 552 { 553 return pause_on_oops_flag == 0; 554 } 555 556 /* 557 * Called when the architecture enters its oops handler, before it prints 558 * anything. If this is the first CPU to oops, and it's oopsing the first 559 * time then let it proceed. 560 * 561 * This is all enabled by the pause_on_oops kernel boot option. We do all 562 * this to ensure that oopses don't scroll off the screen. It has the 563 * side-effect of preventing later-oopsing CPUs from mucking up the display, 564 * too. 565 * 566 * It turns out that the CPU which is allowed to print ends up pausing for 567 * the right duration, whereas all the other CPUs pause for twice as long: 568 * once in oops_enter(), once in oops_exit(). 569 */ 570 void oops_enter(void) 571 { 572 tracing_off(); 573 /* can't trust the integrity of the kernel anymore: */ 574 debug_locks_off(); 575 do_oops_enter_exit(); 576 577 if (sysctl_oops_all_cpu_backtrace) 578 trigger_all_cpu_backtrace(); 579 } 580 581 static void print_oops_end_marker(void) 582 { 583 pr_warn("---[ end trace %016llx ]---\n", 0ULL); 584 } 585 586 /* 587 * Called when the architecture exits its oops handler, after printing 588 * everything. 589 */ 590 void oops_exit(void) 591 { 592 do_oops_enter_exit(); 593 print_oops_end_marker(); 594 kmsg_dump(KMSG_DUMP_OOPS); 595 } 596 597 struct warn_args { 598 const char *fmt; 599 va_list args; 600 }; 601 602 void __warn(const char *file, int line, void *caller, unsigned taint, 603 struct pt_regs *regs, struct warn_args *args) 604 { 605 disable_trace_on_warning(); 606 607 if (file) 608 pr_warn("WARNING: CPU: %d PID: %d at %s:%d %pS\n", 609 raw_smp_processor_id(), current->pid, file, line, 610 caller); 611 else 612 pr_warn("WARNING: CPU: %d PID: %d at %pS\n", 613 raw_smp_processor_id(), current->pid, caller); 614 615 if (args) 616 vprintk(args->fmt, args->args); 617 618 print_modules(); 619 620 if (regs) 621 show_regs(regs); 622 623 if (panic_on_warn) 624 panic("panic_on_warn set ...\n"); 625 626 if (!regs) 627 dump_stack(); 628 629 print_irqtrace_events(current); 630 631 print_oops_end_marker(); 632 trace_error_report_end(ERROR_DETECTOR_WARN, (unsigned long)caller); 633 634 /* Just a warning, don't kill lockdep. */ 635 add_taint(taint, LOCKDEP_STILL_OK); 636 } 637 638 #ifndef __WARN_FLAGS 639 void warn_slowpath_fmt(const char *file, int line, unsigned taint, 640 const char *fmt, ...) 641 { 642 struct warn_args args; 643 644 pr_warn(CUT_HERE); 645 646 if (!fmt) { 647 __warn(file, line, __builtin_return_address(0), taint, 648 NULL, NULL); 649 return; 650 } 651 652 args.fmt = fmt; 653 va_start(args.args, fmt); 654 __warn(file, line, __builtin_return_address(0), taint, NULL, &args); 655 va_end(args.args); 656 } 657 EXPORT_SYMBOL(warn_slowpath_fmt); 658 #else 659 void __warn_printk(const char *fmt, ...) 660 { 661 va_list args; 662 663 pr_warn(CUT_HERE); 664 665 va_start(args, fmt); 666 vprintk(fmt, args); 667 va_end(args); 668 } 669 EXPORT_SYMBOL(__warn_printk); 670 #endif 671 672 #ifdef CONFIG_BUG 673 674 /* Support resetting WARN*_ONCE state */ 675 676 static int clear_warn_once_set(void *data, u64 val) 677 { 678 generic_bug_clear_once(); 679 memset(__start_once, 0, __end_once - __start_once); 680 return 0; 681 } 682 683 DEFINE_DEBUGFS_ATTRIBUTE(clear_warn_once_fops, NULL, clear_warn_once_set, 684 "%lld\n"); 685 686 static __init int register_warn_debugfs(void) 687 { 688 /* Don't care about failure */ 689 debugfs_create_file_unsafe("clear_warn_once", 0200, NULL, NULL, 690 &clear_warn_once_fops); 691 return 0; 692 } 693 694 device_initcall(register_warn_debugfs); 695 #endif 696 697 #ifdef CONFIG_STACKPROTECTOR 698 699 /* 700 * Called when gcc's -fstack-protector feature is used, and 701 * gcc detects corruption of the on-stack canary value 702 */ 703 __visible noinstr void __stack_chk_fail(void) 704 { 705 instrumentation_begin(); 706 panic("stack-protector: Kernel stack is corrupted in: %pB", 707 __builtin_return_address(0)); 708 instrumentation_end(); 709 } 710 EXPORT_SYMBOL(__stack_chk_fail); 711 712 #endif 713 714 core_param(panic, panic_timeout, int, 0644); 715 core_param(panic_print, panic_print, ulong, 0644); 716 core_param(pause_on_oops, pause_on_oops, int, 0644); 717 core_param(panic_on_warn, panic_on_warn, int, 0644); 718 core_param(crash_kexec_post_notifiers, crash_kexec_post_notifiers, bool, 0644); 719 720 static int __init oops_setup(char *s) 721 { 722 if (!s) 723 return -EINVAL; 724 if (!strcmp(s, "panic")) 725 panic_on_oops = 1; 726 return 0; 727 } 728 early_param("oops", oops_setup); 729 730 static int __init panic_on_taint_setup(char *s) 731 { 732 char *taint_str; 733 734 if (!s) 735 return -EINVAL; 736 737 taint_str = strsep(&s, ","); 738 if (kstrtoul(taint_str, 16, &panic_on_taint)) 739 return -EINVAL; 740 741 /* make sure panic_on_taint doesn't hold out-of-range TAINT flags */ 742 panic_on_taint &= TAINT_FLAGS_MAX; 743 744 if (!panic_on_taint) 745 return -EINVAL; 746 747 if (s && !strcmp(s, "nousertaint")) 748 panic_on_taint_nousertaint = true; 749 750 pr_info("panic_on_taint: bitmask=0x%lx nousertaint_mode=%sabled\n", 751 panic_on_taint, panic_on_taint_nousertaint ? "en" : "dis"); 752 753 return 0; 754 } 755 early_param("panic_on_taint", panic_on_taint_setup); 756