1 /* 2 * linux/init/main.c 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 * 6 * GK 2/5/95 - Changed to support mounting root fs via NFS 7 * Added initrd & change_root: Werner Almesberger & Hans Lermen, Feb '96 8 * Moan early if gcc is old, avoiding bogus kernels - Paul Gortmaker, May '96 9 * Simplified starting of init: Michael A. Griffith <grif@acm.org> 10 */ 11 12 #define DEBUG /* Enable initcall_debug */ 13 14 #include <linux/types.h> 15 #include <linux/module.h> 16 #include <linux/proc_fs.h> 17 #include <linux/kernel.h> 18 #include <linux/syscalls.h> 19 #include <linux/stackprotector.h> 20 #include <linux/string.h> 21 #include <linux/ctype.h> 22 #include <linux/delay.h> 23 #include <linux/ioport.h> 24 #include <linux/init.h> 25 #include <linux/initrd.h> 26 #include <linux/bootmem.h> 27 #include <linux/acpi.h> 28 #include <linux/tty.h> 29 #include <linux/percpu.h> 30 #include <linux/kmod.h> 31 #include <linux/vmalloc.h> 32 #include <linux/kernel_stat.h> 33 #include <linux/start_kernel.h> 34 #include <linux/security.h> 35 #include <linux/smp.h> 36 #include <linux/profile.h> 37 #include <linux/rcupdate.h> 38 #include <linux/moduleparam.h> 39 #include <linux/kallsyms.h> 40 #include <linux/writeback.h> 41 #include <linux/cpu.h> 42 #include <linux/cpuset.h> 43 #include <linux/cgroup.h> 44 #include <linux/efi.h> 45 #include <linux/tick.h> 46 #include <linux/interrupt.h> 47 #include <linux/taskstats_kern.h> 48 #include <linux/delayacct.h> 49 #include <linux/unistd.h> 50 #include <linux/rmap.h> 51 #include <linux/mempolicy.h> 52 #include <linux/key.h> 53 #include <linux/buffer_head.h> 54 #include <linux/page_ext.h> 55 #include <linux/debug_locks.h> 56 #include <linux/debugobjects.h> 57 #include <linux/lockdep.h> 58 #include <linux/kmemleak.h> 59 #include <linux/pid_namespace.h> 60 #include <linux/device.h> 61 #include <linux/kthread.h> 62 #include <linux/sched.h> 63 #include <linux/signal.h> 64 #include <linux/idr.h> 65 #include <linux/kgdb.h> 66 #include <linux/ftrace.h> 67 #include <linux/async.h> 68 #include <linux/kmemcheck.h> 69 #include <linux/sfi.h> 70 #include <linux/shmem_fs.h> 71 #include <linux/slab.h> 72 #include <linux/perf_event.h> 73 #include <linux/file.h> 74 #include <linux/ptrace.h> 75 #include <linux/blkdev.h> 76 #include <linux/elevator.h> 77 #include <linux/sched_clock.h> 78 #include <linux/context_tracking.h> 79 #include <linux/random.h> 80 #include <linux/list.h> 81 #include <linux/integrity.h> 82 #include <linux/proc_ns.h> 83 84 #include <asm/io.h> 85 #include <asm/bugs.h> 86 #include <asm/setup.h> 87 #include <asm/sections.h> 88 #include <asm/cacheflush.h> 89 90 #ifdef CONFIG_X86_LOCAL_APIC 91 #include <asm/smp.h> 92 #endif 93 94 static int kernel_init(void *); 95 96 extern void init_IRQ(void); 97 extern void fork_init(unsigned long); 98 extern void radix_tree_init(void); 99 #ifndef CONFIG_DEBUG_RODATA 100 static inline void mark_rodata_ro(void) { } 101 #endif 102 103 /* 104 * Debug helper: via this flag we know that we are in 'early bootup code' 105 * where only the boot processor is running with IRQ disabled. This means 106 * two things - IRQ must not be enabled before the flag is cleared and some 107 * operations which are not allowed with IRQ disabled are allowed while the 108 * flag is set. 109 */ 110 bool early_boot_irqs_disabled __read_mostly; 111 112 enum system_states system_state __read_mostly; 113 EXPORT_SYMBOL(system_state); 114 115 /* 116 * Boot command-line arguments 117 */ 118 #define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT 119 #define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT 120 121 extern void time_init(void); 122 /* Default late time init is NULL. archs can override this later. */ 123 void (*__initdata late_time_init)(void); 124 125 /* Untouched command line saved by arch-specific code. */ 126 char __initdata boot_command_line[COMMAND_LINE_SIZE]; 127 /* Untouched saved command line (eg. for /proc) */ 128 char *saved_command_line; 129 /* Command line for parameter parsing */ 130 static char *static_command_line; 131 /* Command line for per-initcall parameter parsing */ 132 static char *initcall_command_line; 133 134 static char *execute_command; 135 static char *ramdisk_execute_command; 136 137 /* 138 * Used to generate warnings if static_key manipulation functions are used 139 * before jump_label_init is called. 140 */ 141 bool static_key_initialized __read_mostly; 142 EXPORT_SYMBOL_GPL(static_key_initialized); 143 144 /* 145 * If set, this is an indication to the drivers that reset the underlying 146 * device before going ahead with the initialization otherwise driver might 147 * rely on the BIOS and skip the reset operation. 148 * 149 * This is useful if kernel is booting in an unreliable environment. 150 * For ex. kdump situaiton where previous kernel has crashed, BIOS has been 151 * skipped and devices will be in unknown state. 152 */ 153 unsigned int reset_devices; 154 EXPORT_SYMBOL(reset_devices); 155 156 static int __init set_reset_devices(char *str) 157 { 158 reset_devices = 1; 159 return 1; 160 } 161 162 __setup("reset_devices", set_reset_devices); 163 164 static const char *argv_init[MAX_INIT_ARGS+2] = { "init", NULL, }; 165 const char *envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, }; 166 static const char *panic_later, *panic_param; 167 168 extern const struct obs_kernel_param __setup_start[], __setup_end[]; 169 170 static int __init obsolete_checksetup(char *line) 171 { 172 const struct obs_kernel_param *p; 173 int had_early_param = 0; 174 175 p = __setup_start; 176 do { 177 int n = strlen(p->str); 178 if (parameqn(line, p->str, n)) { 179 if (p->early) { 180 /* Already done in parse_early_param? 181 * (Needs exact match on param part). 182 * Keep iterating, as we can have early 183 * params and __setups of same names 8( */ 184 if (line[n] == '\0' || line[n] == '=') 185 had_early_param = 1; 186 } else if (!p->setup_func) { 187 pr_warn("Parameter %s is obsolete, ignored\n", 188 p->str); 189 return 1; 190 } else if (p->setup_func(line + n)) 191 return 1; 192 } 193 p++; 194 } while (p < __setup_end); 195 196 return had_early_param; 197 } 198 199 /* 200 * This should be approx 2 Bo*oMips to start (note initial shift), and will 201 * still work even if initially too large, it will just take slightly longer 202 */ 203 unsigned long loops_per_jiffy = (1<<12); 204 EXPORT_SYMBOL(loops_per_jiffy); 205 206 static int __init debug_kernel(char *str) 207 { 208 console_loglevel = CONSOLE_LOGLEVEL_DEBUG; 209 return 0; 210 } 211 212 static int __init quiet_kernel(char *str) 213 { 214 console_loglevel = CONSOLE_LOGLEVEL_QUIET; 215 return 0; 216 } 217 218 early_param("debug", debug_kernel); 219 early_param("quiet", quiet_kernel); 220 221 static int __init loglevel(char *str) 222 { 223 int newlevel; 224 225 /* 226 * Only update loglevel value when a correct setting was passed, 227 * to prevent blind crashes (when loglevel being set to 0) that 228 * are quite hard to debug 229 */ 230 if (get_option(&str, &newlevel)) { 231 console_loglevel = newlevel; 232 return 0; 233 } 234 235 return -EINVAL; 236 } 237 238 early_param("loglevel", loglevel); 239 240 /* Change NUL term back to "=", to make "param" the whole string. */ 241 static int __init repair_env_string(char *param, char *val, const char *unused) 242 { 243 if (val) { 244 /* param=val or param="val"? */ 245 if (val == param+strlen(param)+1) 246 val[-1] = '='; 247 else if (val == param+strlen(param)+2) { 248 val[-2] = '='; 249 memmove(val-1, val, strlen(val)+1); 250 val--; 251 } else 252 BUG(); 253 } 254 return 0; 255 } 256 257 /* Anything after -- gets handed straight to init. */ 258 static int __init set_init_arg(char *param, char *val, const char *unused) 259 { 260 unsigned int i; 261 262 if (panic_later) 263 return 0; 264 265 repair_env_string(param, val, unused); 266 267 for (i = 0; argv_init[i]; i++) { 268 if (i == MAX_INIT_ARGS) { 269 panic_later = "init"; 270 panic_param = param; 271 return 0; 272 } 273 } 274 argv_init[i] = param; 275 return 0; 276 } 277 278 /* 279 * Unknown boot options get handed to init, unless they look like 280 * unused parameters (modprobe will find them in /proc/cmdline). 281 */ 282 static int __init unknown_bootoption(char *param, char *val, const char *unused) 283 { 284 repair_env_string(param, val, unused); 285 286 /* Handle obsolete-style parameters */ 287 if (obsolete_checksetup(param)) 288 return 0; 289 290 /* Unused module parameter. */ 291 if (strchr(param, '.') && (!val || strchr(param, '.') < val)) 292 return 0; 293 294 if (panic_later) 295 return 0; 296 297 if (val) { 298 /* Environment option */ 299 unsigned int i; 300 for (i = 0; envp_init[i]; i++) { 301 if (i == MAX_INIT_ENVS) { 302 panic_later = "env"; 303 panic_param = param; 304 } 305 if (!strncmp(param, envp_init[i], val - param)) 306 break; 307 } 308 envp_init[i] = param; 309 } else { 310 /* Command line option */ 311 unsigned int i; 312 for (i = 0; argv_init[i]; i++) { 313 if (i == MAX_INIT_ARGS) { 314 panic_later = "init"; 315 panic_param = param; 316 } 317 } 318 argv_init[i] = param; 319 } 320 return 0; 321 } 322 323 static int __init init_setup(char *str) 324 { 325 unsigned int i; 326 327 execute_command = str; 328 /* 329 * In case LILO is going to boot us with default command line, 330 * it prepends "auto" before the whole cmdline which makes 331 * the shell think it should execute a script with such name. 332 * So we ignore all arguments entered _before_ init=... [MJ] 333 */ 334 for (i = 1; i < MAX_INIT_ARGS; i++) 335 argv_init[i] = NULL; 336 return 1; 337 } 338 __setup("init=", init_setup); 339 340 static int __init rdinit_setup(char *str) 341 { 342 unsigned int i; 343 344 ramdisk_execute_command = str; 345 /* See "auto" comment in init_setup */ 346 for (i = 1; i < MAX_INIT_ARGS; i++) 347 argv_init[i] = NULL; 348 return 1; 349 } 350 __setup("rdinit=", rdinit_setup); 351 352 #ifndef CONFIG_SMP 353 static const unsigned int setup_max_cpus = NR_CPUS; 354 #ifdef CONFIG_X86_LOCAL_APIC 355 static void __init smp_init(void) 356 { 357 APIC_init_uniprocessor(); 358 } 359 #else 360 #define smp_init() do { } while (0) 361 #endif 362 363 static inline void setup_nr_cpu_ids(void) { } 364 static inline void smp_prepare_cpus(unsigned int maxcpus) { } 365 #endif 366 367 /* 368 * We need to store the untouched command line for future reference. 369 * We also need to store the touched command line since the parameter 370 * parsing is performed in place, and we should allow a component to 371 * store reference of name/value for future reference. 372 */ 373 static void __init setup_command_line(char *command_line) 374 { 375 saved_command_line = 376 memblock_virt_alloc(strlen(boot_command_line) + 1, 0); 377 initcall_command_line = 378 memblock_virt_alloc(strlen(boot_command_line) + 1, 0); 379 static_command_line = memblock_virt_alloc(strlen(command_line) + 1, 0); 380 strcpy(saved_command_line, boot_command_line); 381 strcpy(static_command_line, command_line); 382 } 383 384 /* 385 * We need to finalize in a non-__init function or else race conditions 386 * between the root thread and the init thread may cause start_kernel to 387 * be reaped by free_initmem before the root thread has proceeded to 388 * cpu_idle. 389 * 390 * gcc-3.4 accidentally inlines this function, so use noinline. 391 */ 392 393 static __initdata DECLARE_COMPLETION(kthreadd_done); 394 395 static noinline void __init_refok rest_init(void) 396 { 397 int pid; 398 399 rcu_scheduler_starting(); 400 /* 401 * We need to spawn init first so that it obtains pid 1, however 402 * the init task will end up wanting to create kthreads, which, if 403 * we schedule it before we create kthreadd, will OOPS. 404 */ 405 kernel_thread(kernel_init, NULL, CLONE_FS); 406 numa_default_policy(); 407 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES); 408 rcu_read_lock(); 409 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns); 410 rcu_read_unlock(); 411 complete(&kthreadd_done); 412 413 /* 414 * The boot idle thread must execute schedule() 415 * at least once to get things moving: 416 */ 417 init_idle_bootup_task(current); 418 schedule_preempt_disabled(); 419 /* Call into cpu_idle with preempt disabled */ 420 cpu_startup_entry(CPUHP_ONLINE); 421 } 422 423 /* Check for early params. */ 424 static int __init do_early_param(char *param, char *val, const char *unused) 425 { 426 const struct obs_kernel_param *p; 427 428 for (p = __setup_start; p < __setup_end; p++) { 429 if ((p->early && parameq(param, p->str)) || 430 (strcmp(param, "console") == 0 && 431 strcmp(p->str, "earlycon") == 0) 432 ) { 433 if (p->setup_func(val) != 0) 434 pr_warn("Malformed early option '%s'\n", param); 435 } 436 } 437 /* We accept everything at this stage. */ 438 return 0; 439 } 440 441 void __init parse_early_options(char *cmdline) 442 { 443 parse_args("early options", cmdline, NULL, 0, 0, 0, do_early_param); 444 } 445 446 /* Arch code calls this early on, or if not, just before other parsing. */ 447 void __init parse_early_param(void) 448 { 449 static int done __initdata; 450 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; 451 452 if (done) 453 return; 454 455 /* All fall through to do_early_param. */ 456 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); 457 parse_early_options(tmp_cmdline); 458 done = 1; 459 } 460 461 /* 462 * Activate the first processor. 463 */ 464 465 static void __init boot_cpu_init(void) 466 { 467 int cpu = smp_processor_id(); 468 /* Mark the boot cpu "present", "online" etc for SMP and UP case */ 469 set_cpu_online(cpu, true); 470 set_cpu_active(cpu, true); 471 set_cpu_present(cpu, true); 472 set_cpu_possible(cpu, true); 473 } 474 475 void __init __weak smp_setup_processor_id(void) 476 { 477 } 478 479 # if THREAD_SIZE >= PAGE_SIZE 480 void __init __weak thread_info_cache_init(void) 481 { 482 } 483 #endif 484 485 /* 486 * Set up kernel memory allocators 487 */ 488 static void __init mm_init(void) 489 { 490 /* 491 * page_ext requires contiguous pages, 492 * bigger than MAX_ORDER unless SPARSEMEM. 493 */ 494 page_ext_init_flatmem(); 495 mem_init(); 496 kmem_cache_init(); 497 percpu_init_late(); 498 pgtable_init(); 499 vmalloc_init(); 500 } 501 502 asmlinkage __visible void __init start_kernel(void) 503 { 504 char *command_line; 505 char *after_dashes; 506 507 /* 508 * Need to run as early as possible, to initialize the 509 * lockdep hash: 510 */ 511 lockdep_init(); 512 set_task_stack_end_magic(&init_task); 513 smp_setup_processor_id(); 514 debug_objects_early_init(); 515 516 /* 517 * Set up the the initial canary ASAP: 518 */ 519 boot_init_stack_canary(); 520 521 cgroup_init_early(); 522 523 local_irq_disable(); 524 early_boot_irqs_disabled = true; 525 526 /* 527 * Interrupts are still disabled. Do necessary setups, then 528 * enable them 529 */ 530 boot_cpu_init(); 531 page_address_init(); 532 pr_notice("%s", linux_banner); 533 setup_arch(&command_line); 534 mm_init_cpumask(&init_mm); 535 setup_command_line(command_line); 536 setup_nr_cpu_ids(); 537 setup_per_cpu_areas(); 538 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */ 539 540 build_all_zonelists(NULL, NULL); 541 page_alloc_init(); 542 543 pr_notice("Kernel command line: %s\n", boot_command_line); 544 parse_early_param(); 545 after_dashes = parse_args("Booting kernel", 546 static_command_line, __start___param, 547 __stop___param - __start___param, 548 -1, -1, &unknown_bootoption); 549 if (!IS_ERR_OR_NULL(after_dashes)) 550 parse_args("Setting init args", after_dashes, NULL, 0, -1, -1, 551 set_init_arg); 552 553 jump_label_init(); 554 555 /* 556 * These use large bootmem allocations and must precede 557 * kmem_cache_init() 558 */ 559 setup_log_buf(0); 560 pidhash_init(); 561 vfs_caches_init_early(); 562 sort_main_extable(); 563 trap_init(); 564 mm_init(); 565 566 /* 567 * Set up the scheduler prior starting any interrupts (such as the 568 * timer interrupt). Full topology setup happens at smp_init() 569 * time - but meanwhile we still have a functioning scheduler. 570 */ 571 sched_init(); 572 /* 573 * Disable preemption - early bootup scheduling is extremely 574 * fragile until we cpu_idle() for the first time. 575 */ 576 preempt_disable(); 577 if (WARN(!irqs_disabled(), 578 "Interrupts were enabled *very* early, fixing it\n")) 579 local_irq_disable(); 580 idr_init_cache(); 581 rcu_init(); 582 583 /* trace_printk() and trace points may be used after this */ 584 trace_init(); 585 586 context_tracking_init(); 587 radix_tree_init(); 588 /* init some links before init_ISA_irqs() */ 589 early_irq_init(); 590 init_IRQ(); 591 tick_init(); 592 rcu_init_nohz(); 593 init_timers(); 594 hrtimers_init(); 595 softirq_init(); 596 timekeeping_init(); 597 time_init(); 598 sched_clock_postinit(); 599 perf_event_init(); 600 profile_init(); 601 call_function_init(); 602 WARN(!irqs_disabled(), "Interrupts were enabled early\n"); 603 early_boot_irqs_disabled = false; 604 local_irq_enable(); 605 606 kmem_cache_init_late(); 607 608 /* 609 * HACK ALERT! This is early. We're enabling the console before 610 * we've done PCI setups etc, and console_init() must be aware of 611 * this. But we do want output early, in case something goes wrong. 612 */ 613 console_init(); 614 if (panic_later) 615 panic("Too many boot %s vars at `%s'", panic_later, 616 panic_param); 617 618 lockdep_info(); 619 620 /* 621 * Need to run this when irqs are enabled, because it wants 622 * to self-test [hard/soft]-irqs on/off lock inversion bugs 623 * too: 624 */ 625 locking_selftest(); 626 627 #ifdef CONFIG_BLK_DEV_INITRD 628 if (initrd_start && !initrd_below_start_ok && 629 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) { 630 pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n", 631 page_to_pfn(virt_to_page((void *)initrd_start)), 632 min_low_pfn); 633 initrd_start = 0; 634 } 635 #endif 636 page_ext_init(); 637 debug_objects_mem_init(); 638 kmemleak_init(); 639 setup_per_cpu_pageset(); 640 numa_policy_init(); 641 if (late_time_init) 642 late_time_init(); 643 sched_clock_init(); 644 calibrate_delay(); 645 pidmap_init(); 646 anon_vma_init(); 647 acpi_early_init(); 648 #ifdef CONFIG_X86 649 if (efi_enabled(EFI_RUNTIME_SERVICES)) 650 efi_enter_virtual_mode(); 651 #endif 652 #ifdef CONFIG_X86_ESPFIX64 653 /* Should be run before the first non-init thread is created */ 654 init_espfix_bsp(); 655 #endif 656 thread_info_cache_init(); 657 cred_init(); 658 fork_init(totalram_pages); 659 proc_caches_init(); 660 buffer_init(); 661 key_init(); 662 security_init(); 663 dbg_late_init(); 664 vfs_caches_init(totalram_pages); 665 signals_init(); 666 /* rootfs populating might need page-writeback */ 667 page_writeback_init(); 668 proc_root_init(); 669 nsfs_init(); 670 cgroup_init(); 671 cpuset_init(); 672 taskstats_init_early(); 673 delayacct_init(); 674 675 check_bugs(); 676 677 sfi_init_late(); 678 679 if (efi_enabled(EFI_RUNTIME_SERVICES)) { 680 efi_late_init(); 681 efi_free_boot_services(); 682 } 683 684 ftrace_init(); 685 686 /* Do the rest non-__init'ed, we're now alive */ 687 rest_init(); 688 } 689 690 /* Call all constructor functions linked into the kernel. */ 691 static void __init do_ctors(void) 692 { 693 #ifdef CONFIG_CONSTRUCTORS 694 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start; 695 696 for (; fn < (ctor_fn_t *) __ctors_end; fn++) 697 (*fn)(); 698 #endif 699 } 700 701 bool initcall_debug; 702 core_param(initcall_debug, initcall_debug, bool, 0644); 703 704 #ifdef CONFIG_KALLSYMS 705 struct blacklist_entry { 706 struct list_head next; 707 char *buf; 708 }; 709 710 static __initdata_or_module LIST_HEAD(blacklisted_initcalls); 711 712 static int __init initcall_blacklist(char *str) 713 { 714 char *str_entry; 715 struct blacklist_entry *entry; 716 717 /* str argument is a comma-separated list of functions */ 718 do { 719 str_entry = strsep(&str, ","); 720 if (str_entry) { 721 pr_debug("blacklisting initcall %s\n", str_entry); 722 entry = alloc_bootmem(sizeof(*entry)); 723 entry->buf = alloc_bootmem(strlen(str_entry) + 1); 724 strcpy(entry->buf, str_entry); 725 list_add(&entry->next, &blacklisted_initcalls); 726 } 727 } while (str_entry); 728 729 return 0; 730 } 731 732 static bool __init_or_module initcall_blacklisted(initcall_t fn) 733 { 734 struct list_head *tmp; 735 struct blacklist_entry *entry; 736 char *fn_name; 737 738 fn_name = kasprintf(GFP_KERNEL, "%pf", fn); 739 if (!fn_name) 740 return false; 741 742 list_for_each(tmp, &blacklisted_initcalls) { 743 entry = list_entry(tmp, struct blacklist_entry, next); 744 if (!strcmp(fn_name, entry->buf)) { 745 pr_debug("initcall %s blacklisted\n", fn_name); 746 kfree(fn_name); 747 return true; 748 } 749 } 750 751 kfree(fn_name); 752 return false; 753 } 754 #else 755 static int __init initcall_blacklist(char *str) 756 { 757 pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n"); 758 return 0; 759 } 760 761 static bool __init_or_module initcall_blacklisted(initcall_t fn) 762 { 763 return false; 764 } 765 #endif 766 __setup("initcall_blacklist=", initcall_blacklist); 767 768 static int __init_or_module do_one_initcall_debug(initcall_t fn) 769 { 770 ktime_t calltime, delta, rettime; 771 unsigned long long duration; 772 int ret; 773 774 printk(KERN_DEBUG "calling %pF @ %i\n", fn, task_pid_nr(current)); 775 calltime = ktime_get(); 776 ret = fn(); 777 rettime = ktime_get(); 778 delta = ktime_sub(rettime, calltime); 779 duration = (unsigned long long) ktime_to_ns(delta) >> 10; 780 printk(KERN_DEBUG "initcall %pF returned %d after %lld usecs\n", 781 fn, ret, duration); 782 783 return ret; 784 } 785 786 int __init_or_module do_one_initcall(initcall_t fn) 787 { 788 int count = preempt_count(); 789 int ret; 790 char msgbuf[64]; 791 792 if (initcall_blacklisted(fn)) 793 return -EPERM; 794 795 if (initcall_debug) 796 ret = do_one_initcall_debug(fn); 797 else 798 ret = fn(); 799 800 msgbuf[0] = 0; 801 802 if (preempt_count() != count) { 803 sprintf(msgbuf, "preemption imbalance "); 804 preempt_count_set(count); 805 } 806 if (irqs_disabled()) { 807 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf)); 808 local_irq_enable(); 809 } 810 WARN(msgbuf[0], "initcall %pF returned with %s\n", fn, msgbuf); 811 812 return ret; 813 } 814 815 816 extern initcall_t __initcall_start[]; 817 extern initcall_t __initcall0_start[]; 818 extern initcall_t __initcall1_start[]; 819 extern initcall_t __initcall2_start[]; 820 extern initcall_t __initcall3_start[]; 821 extern initcall_t __initcall4_start[]; 822 extern initcall_t __initcall5_start[]; 823 extern initcall_t __initcall6_start[]; 824 extern initcall_t __initcall7_start[]; 825 extern initcall_t __initcall_end[]; 826 827 static initcall_t *initcall_levels[] __initdata = { 828 __initcall0_start, 829 __initcall1_start, 830 __initcall2_start, 831 __initcall3_start, 832 __initcall4_start, 833 __initcall5_start, 834 __initcall6_start, 835 __initcall7_start, 836 __initcall_end, 837 }; 838 839 /* Keep these in sync with initcalls in include/linux/init.h */ 840 static char *initcall_level_names[] __initdata = { 841 "early", 842 "core", 843 "postcore", 844 "arch", 845 "subsys", 846 "fs", 847 "device", 848 "late", 849 }; 850 851 static void __init do_initcall_level(int level) 852 { 853 initcall_t *fn; 854 855 strcpy(initcall_command_line, saved_command_line); 856 parse_args(initcall_level_names[level], 857 initcall_command_line, __start___param, 858 __stop___param - __start___param, 859 level, level, 860 &repair_env_string); 861 862 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++) 863 do_one_initcall(*fn); 864 } 865 866 static void __init do_initcalls(void) 867 { 868 int level; 869 870 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) 871 do_initcall_level(level); 872 } 873 874 /* 875 * Ok, the machine is now initialized. None of the devices 876 * have been touched yet, but the CPU subsystem is up and 877 * running, and memory and process management works. 878 * 879 * Now we can finally start doing some real work.. 880 */ 881 static void __init do_basic_setup(void) 882 { 883 cpuset_init_smp(); 884 usermodehelper_init(); 885 shmem_init(); 886 driver_init(); 887 init_irq_proc(); 888 do_ctors(); 889 usermodehelper_enable(); 890 do_initcalls(); 891 random_int_secret_init(); 892 } 893 894 static void __init do_pre_smp_initcalls(void) 895 { 896 initcall_t *fn; 897 898 for (fn = __initcall_start; fn < __initcall0_start; fn++) 899 do_one_initcall(*fn); 900 } 901 902 /* 903 * This function requests modules which should be loaded by default and is 904 * called twice right after initrd is mounted and right before init is 905 * exec'd. If such modules are on either initrd or rootfs, they will be 906 * loaded before control is passed to userland. 907 */ 908 void __init load_default_modules(void) 909 { 910 load_default_elevator_module(); 911 } 912 913 static int run_init_process(const char *init_filename) 914 { 915 argv_init[0] = init_filename; 916 return do_execve(getname_kernel(init_filename), 917 (const char __user *const __user *)argv_init, 918 (const char __user *const __user *)envp_init); 919 } 920 921 static int try_to_run_init_process(const char *init_filename) 922 { 923 int ret; 924 925 ret = run_init_process(init_filename); 926 927 if (ret && ret != -ENOENT) { 928 pr_err("Starting init: %s exists but couldn't execute it (error %d)\n", 929 init_filename, ret); 930 } 931 932 return ret; 933 } 934 935 static noinline void __init kernel_init_freeable(void); 936 937 static int __ref kernel_init(void *unused) 938 { 939 int ret; 940 941 kernel_init_freeable(); 942 /* need to finish all async __init code before freeing the memory */ 943 async_synchronize_full(); 944 free_initmem(); 945 mark_rodata_ro(); 946 system_state = SYSTEM_RUNNING; 947 numa_default_policy(); 948 949 flush_delayed_fput(); 950 951 if (ramdisk_execute_command) { 952 ret = run_init_process(ramdisk_execute_command); 953 if (!ret) 954 return 0; 955 pr_err("Failed to execute %s (error %d)\n", 956 ramdisk_execute_command, ret); 957 } 958 959 /* 960 * We try each of these until one succeeds. 961 * 962 * The Bourne shell can be used instead of init if we are 963 * trying to recover a really broken machine. 964 */ 965 if (execute_command) { 966 ret = run_init_process(execute_command); 967 if (!ret) 968 return 0; 969 #ifndef CONFIG_INIT_FALLBACK 970 panic("Requested init %s failed (error %d).", 971 execute_command, ret); 972 #else 973 pr_err("Failed to execute %s (error %d). Attempting defaults...\n", 974 execute_command, ret); 975 #endif 976 } 977 if (!try_to_run_init_process("/sbin/init") || 978 !try_to_run_init_process("/etc/init") || 979 !try_to_run_init_process("/bin/init") || 980 !try_to_run_init_process("/bin/sh")) 981 return 0; 982 983 panic("No working init found. Try passing init= option to kernel. " 984 "See Linux Documentation/init.txt for guidance."); 985 } 986 987 static noinline void __init kernel_init_freeable(void) 988 { 989 /* 990 * Wait until kthreadd is all set-up. 991 */ 992 wait_for_completion(&kthreadd_done); 993 994 /* Now the scheduler is fully set up and can do blocking allocations */ 995 gfp_allowed_mask = __GFP_BITS_MASK; 996 997 /* 998 * init can allocate pages on any node 999 */ 1000 set_mems_allowed(node_states[N_MEMORY]); 1001 /* 1002 * init can run on any cpu. 1003 */ 1004 set_cpus_allowed_ptr(current, cpu_all_mask); 1005 1006 cad_pid = task_pid(current); 1007 1008 smp_prepare_cpus(setup_max_cpus); 1009 1010 do_pre_smp_initcalls(); 1011 lockup_detector_init(); 1012 1013 smp_init(); 1014 sched_init_smp(); 1015 1016 do_basic_setup(); 1017 1018 /* Open the /dev/console on the rootfs, this should never fail */ 1019 if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0) 1020 pr_err("Warning: unable to open an initial console.\n"); 1021 1022 (void) sys_dup(0); 1023 (void) sys_dup(0); 1024 /* 1025 * check if there is an early userspace init. If yes, let it do all 1026 * the work 1027 */ 1028 1029 if (!ramdisk_execute_command) 1030 ramdisk_execute_command = "/init"; 1031 1032 if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) { 1033 ramdisk_execute_command = NULL; 1034 prepare_namespace(); 1035 } 1036 1037 /* 1038 * Ok, we have completed the initial bootup, and 1039 * we're essentially up and running. Get rid of the 1040 * initmem segments and start the user-mode stuff.. 1041 * 1042 * rootfs is available now, try loading the public keys 1043 * and default modules 1044 */ 1045 1046 integrity_load_keys(); 1047 load_default_modules(); 1048 } 1049