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