1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/init/main.c 4 * 5 * Copyright (C) 1991, 1992 Linus Torvalds 6 * 7 * GK 2/5/95 - Changed to support mounting root fs via NFS 8 * Added initrd & change_root: Werner Almesberger & Hans Lermen, Feb '96 9 * Moan early if gcc is old, avoiding bogus kernels - Paul Gortmaker, May '96 10 * Simplified starting of init: Michael A. Griffith <grif@acm.org> 11 */ 12 13 #define DEBUG /* Enable initcall_debug */ 14 15 #include <linux/types.h> 16 #include <linux/extable.h> 17 #include <linux/module.h> 18 #include <linux/proc_fs.h> 19 #include <linux/binfmts.h> 20 #include <linux/kernel.h> 21 #include <linux/syscalls.h> 22 #include <linux/stackprotector.h> 23 #include <linux/string.h> 24 #include <linux/ctype.h> 25 #include <linux/delay.h> 26 #include <linux/ioport.h> 27 #include <linux/init.h> 28 #include <linux/initrd.h> 29 #include <linux/memblock.h> 30 #include <linux/acpi.h> 31 #include <linux/bootconfig.h> 32 #include <linux/console.h> 33 #include <linux/nmi.h> 34 #include <linux/percpu.h> 35 #include <linux/kmod.h> 36 #include <linux/kprobes.h> 37 #include <linux/kmsan.h> 38 #include <linux/vmalloc.h> 39 #include <linux/kernel_stat.h> 40 #include <linux/start_kernel.h> 41 #include <linux/security.h> 42 #include <linux/smp.h> 43 #include <linux/profile.h> 44 #include <linux/kfence.h> 45 #include <linux/rcupdate.h> 46 #include <linux/srcu.h> 47 #include <linux/moduleparam.h> 48 #include <linux/kallsyms.h> 49 #include <linux/buildid.h> 50 #include <linux/writeback.h> 51 #include <linux/cpu.h> 52 #include <linux/cpuset.h> 53 #include <linux/cgroup.h> 54 #include <linux/efi.h> 55 #include <linux/tick.h> 56 #include <linux/sched/isolation.h> 57 #include <linux/interrupt.h> 58 #include <linux/taskstats_kern.h> 59 #include <linux/delayacct.h> 60 #include <linux/unistd.h> 61 #include <linux/utsname.h> 62 #include <linux/rmap.h> 63 #include <linux/mempolicy.h> 64 #include <linux/key.h> 65 #include <linux/debug_locks.h> 66 #include <linux/debugobjects.h> 67 #include <linux/lockdep.h> 68 #include <linux/kmemleak.h> 69 #include <linux/padata.h> 70 #include <linux/pid_namespace.h> 71 #include <linux/device/driver.h> 72 #include <linux/kthread.h> 73 #include <linux/sched.h> 74 #include <linux/sched/init.h> 75 #include <linux/signal.h> 76 #include <linux/idr.h> 77 #include <linux/kgdb.h> 78 #include <linux/ftrace.h> 79 #include <linux/async.h> 80 #include <linux/shmem_fs.h> 81 #include <linux/slab.h> 82 #include <linux/perf_event.h> 83 #include <linux/ptrace.h> 84 #include <linux/pti.h> 85 #include <linux/blkdev.h> 86 #include <linux/sched/clock.h> 87 #include <linux/sched/task.h> 88 #include <linux/sched/task_stack.h> 89 #include <linux/context_tracking.h> 90 #include <linux/random.h> 91 #include <linux/moduleloader.h> 92 #include <linux/list.h> 93 #include <linux/integrity.h> 94 #include <linux/proc_ns.h> 95 #include <linux/io.h> 96 #include <linux/cache.h> 97 #include <linux/rodata_test.h> 98 #include <linux/jump_label.h> 99 #include <linux/kcsan.h> 100 #include <linux/init_syscalls.h> 101 #include <linux/stackdepot.h> 102 #include <linux/randomize_kstack.h> 103 #include <linux/pidfs.h> 104 #include <linux/ptdump.h> 105 #include <net/net_namespace.h> 106 107 #include <asm/io.h> 108 #include <asm/setup.h> 109 #include <asm/sections.h> 110 #include <asm/cacheflush.h> 111 112 #define CREATE_TRACE_POINTS 113 #include <trace/events/initcall.h> 114 115 #include <kunit/test.h> 116 117 static int kernel_init(void *); 118 119 /* 120 * Debug helper: via this flag we know that we are in 'early bootup code' 121 * where only the boot processor is running with IRQ disabled. This means 122 * two things - IRQ must not be enabled before the flag is cleared and some 123 * operations which are not allowed with IRQ disabled are allowed while the 124 * flag is set. 125 */ 126 bool early_boot_irqs_disabled __read_mostly; 127 128 enum system_states system_state __read_mostly; 129 EXPORT_SYMBOL(system_state); 130 131 /* 132 * Boot command-line arguments 133 */ 134 #define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT 135 #define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT 136 137 /* Default late time init is NULL. archs can override this later. */ 138 void (*__initdata late_time_init)(void); 139 140 /* Untouched command line saved by arch-specific code. */ 141 char __initdata boot_command_line[COMMAND_LINE_SIZE]; 142 /* Untouched saved command line (eg. for /proc) */ 143 char *saved_command_line __ro_after_init; 144 unsigned int saved_command_line_len __ro_after_init; 145 /* Command line for parameter parsing */ 146 static char *static_command_line; 147 /* Untouched extra command line */ 148 static char *extra_command_line; 149 /* Extra init arguments */ 150 static char *extra_init_args; 151 152 #ifdef CONFIG_BOOT_CONFIG 153 /* Is bootconfig on command line? */ 154 static bool bootconfig_found; 155 static size_t initargs_offs; 156 #else 157 # define bootconfig_found false 158 # define initargs_offs 0 159 #endif 160 161 static char *execute_command; 162 static char *ramdisk_execute_command = "/init"; 163 164 /* 165 * Used to generate warnings if static_key manipulation functions are used 166 * before jump_label_init is called. 167 */ 168 bool static_key_initialized __read_mostly; 169 EXPORT_SYMBOL_GPL(static_key_initialized); 170 171 /* 172 * If set, this is an indication to the drivers that reset the underlying 173 * device before going ahead with the initialization otherwise driver might 174 * rely on the BIOS and skip the reset operation. 175 * 176 * This is useful if kernel is booting in an unreliable environment. 177 * For ex. kdump situation where previous kernel has crashed, BIOS has been 178 * skipped and devices will be in unknown state. 179 */ 180 unsigned int reset_devices; 181 EXPORT_SYMBOL(reset_devices); 182 183 static int __init set_reset_devices(char *str) 184 { 185 reset_devices = 1; 186 return 1; 187 } 188 189 __setup("reset_devices", set_reset_devices); 190 191 static const char *argv_init[MAX_INIT_ARGS+2] = { "init", NULL, }; 192 const char *envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, }; 193 static const char *panic_later, *panic_param; 194 195 static bool __init obsolete_checksetup(char *line) 196 { 197 const struct obs_kernel_param *p; 198 bool had_early_param = false; 199 200 p = __setup_start; 201 do { 202 int n = strlen(p->str); 203 if (parameqn(line, p->str, n)) { 204 if (p->early) { 205 /* Already done in parse_early_param? 206 * (Needs exact match on param part). 207 * Keep iterating, as we can have early 208 * params and __setups of same names 8( */ 209 if (line[n] == '\0' || line[n] == '=') 210 had_early_param = true; 211 } else if (!p->setup_func) { 212 pr_warn("Parameter %s is obsolete, ignored\n", 213 p->str); 214 return true; 215 } else if (p->setup_func(line + n)) 216 return true; 217 } 218 p++; 219 } while (p < __setup_end); 220 221 return had_early_param; 222 } 223 224 /* 225 * This should be approx 2 Bo*oMips to start (note initial shift), and will 226 * still work even if initially too large, it will just take slightly longer 227 */ 228 unsigned long loops_per_jiffy = (1<<12); 229 EXPORT_SYMBOL(loops_per_jiffy); 230 231 static int __init debug_kernel(char *str) 232 { 233 console_loglevel = CONSOLE_LOGLEVEL_DEBUG; 234 return 0; 235 } 236 237 static int __init quiet_kernel(char *str) 238 { 239 console_loglevel = CONSOLE_LOGLEVEL_QUIET; 240 return 0; 241 } 242 243 early_param("debug", debug_kernel); 244 early_param("quiet", quiet_kernel); 245 246 static int __init loglevel(char *str) 247 { 248 int newlevel; 249 250 /* 251 * Only update loglevel value when a correct setting was passed, 252 * to prevent blind crashes (when loglevel being set to 0) that 253 * are quite hard to debug 254 */ 255 if (get_option(&str, &newlevel)) { 256 console_loglevel = newlevel; 257 return 0; 258 } 259 260 return -EINVAL; 261 } 262 263 early_param("loglevel", loglevel); 264 265 #ifdef CONFIG_BLK_DEV_INITRD 266 static void * __init get_boot_config_from_initrd(size_t *_size) 267 { 268 u32 size, csum; 269 char *data; 270 u32 *hdr; 271 int i; 272 273 if (!initrd_end) 274 return NULL; 275 276 data = (char *)initrd_end - BOOTCONFIG_MAGIC_LEN; 277 /* 278 * Since Grub may align the size of initrd to 4, we must 279 * check the preceding 3 bytes as well. 280 */ 281 for (i = 0; i < 4; i++) { 282 if (!memcmp(data, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN)) 283 goto found; 284 data--; 285 } 286 return NULL; 287 288 found: 289 hdr = (u32 *)(data - 8); 290 size = le32_to_cpu(hdr[0]); 291 csum = le32_to_cpu(hdr[1]); 292 293 data = ((void *)hdr) - size; 294 if ((unsigned long)data < initrd_start) { 295 pr_err("bootconfig size %d is greater than initrd size %ld\n", 296 size, initrd_end - initrd_start); 297 return NULL; 298 } 299 300 if (xbc_calc_checksum(data, size) != csum) { 301 pr_err("bootconfig checksum failed\n"); 302 return NULL; 303 } 304 305 /* Remove bootconfig from initramfs/initrd */ 306 initrd_end = (unsigned long)data; 307 if (_size) 308 *_size = size; 309 310 return data; 311 } 312 #else 313 static void * __init get_boot_config_from_initrd(size_t *_size) 314 { 315 return NULL; 316 } 317 #endif 318 319 #ifdef CONFIG_BOOT_CONFIG 320 321 static char xbc_namebuf[XBC_KEYLEN_MAX] __initdata; 322 323 #define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0) 324 325 static int __init xbc_snprint_cmdline(char *buf, size_t size, 326 struct xbc_node *root) 327 { 328 struct xbc_node *knode, *vnode; 329 char *end = buf + size; 330 const char *val, *q; 331 int ret; 332 333 xbc_node_for_each_key_value(root, knode, val) { 334 ret = xbc_node_compose_key_after(root, knode, 335 xbc_namebuf, XBC_KEYLEN_MAX); 336 if (ret < 0) 337 return ret; 338 339 vnode = xbc_node_get_child(knode); 340 if (!vnode) { 341 ret = snprintf(buf, rest(buf, end), "%s ", xbc_namebuf); 342 if (ret < 0) 343 return ret; 344 buf += ret; 345 continue; 346 } 347 xbc_array_for_each_value(vnode, val) { 348 /* 349 * For prettier and more readable /proc/cmdline, only 350 * quote the value when necessary, i.e. when it contains 351 * whitespace. 352 */ 353 q = strpbrk(val, " \t\r\n") ? "\"" : ""; 354 ret = snprintf(buf, rest(buf, end), "%s=%s%s%s ", 355 xbc_namebuf, q, val, q); 356 if (ret < 0) 357 return ret; 358 buf += ret; 359 } 360 } 361 362 return buf - (end - size); 363 } 364 #undef rest 365 366 /* Make an extra command line under given key word */ 367 static char * __init xbc_make_cmdline(const char *key) 368 { 369 struct xbc_node *root; 370 char *new_cmdline; 371 int ret, len = 0; 372 373 root = xbc_find_node(key); 374 if (!root) 375 return NULL; 376 377 /* Count required buffer size */ 378 len = xbc_snprint_cmdline(NULL, 0, root); 379 if (len <= 0) 380 return NULL; 381 382 new_cmdline = memblock_alloc(len + 1, SMP_CACHE_BYTES); 383 if (!new_cmdline) { 384 pr_err("Failed to allocate memory for extra kernel cmdline.\n"); 385 return NULL; 386 } 387 388 ret = xbc_snprint_cmdline(new_cmdline, len + 1, root); 389 if (ret < 0 || ret > len) { 390 pr_err("Failed to print extra kernel cmdline.\n"); 391 memblock_free(new_cmdline, len + 1); 392 return NULL; 393 } 394 395 return new_cmdline; 396 } 397 398 static int __init bootconfig_params(char *param, char *val, 399 const char *unused, void *arg) 400 { 401 if (strcmp(param, "bootconfig") == 0) { 402 bootconfig_found = true; 403 } 404 return 0; 405 } 406 407 static int __init warn_bootconfig(char *str) 408 { 409 /* The 'bootconfig' has been handled by bootconfig_params(). */ 410 return 0; 411 } 412 413 static void __init setup_boot_config(void) 414 { 415 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; 416 const char *msg, *data; 417 int pos, ret; 418 size_t size; 419 char *err; 420 421 /* Cut out the bootconfig data even if we have no bootconfig option */ 422 data = get_boot_config_from_initrd(&size); 423 /* If there is no bootconfig in initrd, try embedded one. */ 424 if (!data) 425 data = xbc_get_embedded_bootconfig(&size); 426 427 strscpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); 428 err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL, 429 bootconfig_params); 430 431 if (IS_ERR(err) || !(bootconfig_found || IS_ENABLED(CONFIG_BOOT_CONFIG_FORCE))) 432 return; 433 434 /* parse_args() stops at the next param of '--' and returns an address */ 435 if (err) 436 initargs_offs = err - tmp_cmdline; 437 438 if (!data) { 439 /* If user intended to use bootconfig, show an error level message */ 440 if (bootconfig_found) 441 pr_err("'bootconfig' found on command line, but no bootconfig found\n"); 442 else 443 pr_info("No bootconfig data provided, so skipping bootconfig"); 444 return; 445 } 446 447 if (size >= XBC_DATA_MAX) { 448 pr_err("bootconfig size %ld greater than max size %d\n", 449 (long)size, XBC_DATA_MAX); 450 return; 451 } 452 453 ret = xbc_init(data, size, &msg, &pos); 454 if (ret < 0) { 455 if (pos < 0) 456 pr_err("Failed to init bootconfig: %s.\n", msg); 457 else 458 pr_err("Failed to parse bootconfig: %s at %d.\n", 459 msg, pos); 460 } else { 461 xbc_get_info(&ret, NULL); 462 pr_info("Load bootconfig: %ld bytes %d nodes\n", (long)size, ret); 463 /* keys starting with "kernel." are passed via cmdline */ 464 extra_command_line = xbc_make_cmdline("kernel"); 465 /* Also, "init." keys are init arguments */ 466 extra_init_args = xbc_make_cmdline("init"); 467 } 468 return; 469 } 470 471 static void __init exit_boot_config(void) 472 { 473 xbc_exit(); 474 } 475 476 #else /* !CONFIG_BOOT_CONFIG */ 477 478 static void __init setup_boot_config(void) 479 { 480 /* Remove bootconfig data from initrd */ 481 get_boot_config_from_initrd(NULL); 482 } 483 484 static int __init warn_bootconfig(char *str) 485 { 486 pr_warn("WARNING: 'bootconfig' found on the kernel command line but CONFIG_BOOT_CONFIG is not set.\n"); 487 return 0; 488 } 489 490 #define exit_boot_config() do {} while (0) 491 492 #endif /* CONFIG_BOOT_CONFIG */ 493 494 early_param("bootconfig", warn_bootconfig); 495 496 bool __init cmdline_has_extra_options(void) 497 { 498 return extra_command_line || extra_init_args; 499 } 500 501 /* Change NUL term back to "=", to make "param" the whole string. */ 502 static void __init repair_env_string(char *param, char *val) 503 { 504 if (val) { 505 /* param=val or param="val"? */ 506 if (val == param+strlen(param)+1) 507 val[-1] = '='; 508 else if (val == param+strlen(param)+2) { 509 val[-2] = '='; 510 memmove(val-1, val, strlen(val)+1); 511 } else 512 BUG(); 513 } 514 } 515 516 /* Anything after -- gets handed straight to init. */ 517 static int __init set_init_arg(char *param, char *val, 518 const char *unused, void *arg) 519 { 520 unsigned int i; 521 522 if (panic_later) 523 return 0; 524 525 repair_env_string(param, val); 526 527 for (i = 0; argv_init[i]; i++) { 528 if (i == MAX_INIT_ARGS) { 529 panic_later = "init"; 530 panic_param = param; 531 return 0; 532 } 533 } 534 argv_init[i] = param; 535 return 0; 536 } 537 538 /* 539 * Unknown boot options get handed to init, unless they look like 540 * unused parameters (modprobe will find them in /proc/cmdline). 541 */ 542 static int __init unknown_bootoption(char *param, char *val, 543 const char *unused, void *arg) 544 { 545 size_t len = strlen(param); 546 547 /* Handle params aliased to sysctls */ 548 if (sysctl_is_alias(param)) 549 return 0; 550 551 repair_env_string(param, val); 552 553 /* Handle obsolete-style parameters */ 554 if (obsolete_checksetup(param)) 555 return 0; 556 557 /* Unused module parameter. */ 558 if (strnchr(param, len, '.')) 559 return 0; 560 561 if (panic_later) 562 return 0; 563 564 if (val) { 565 /* Environment option */ 566 unsigned int i; 567 for (i = 0; envp_init[i]; i++) { 568 if (i == MAX_INIT_ENVS) { 569 panic_later = "env"; 570 panic_param = param; 571 } 572 if (!strncmp(param, envp_init[i], len+1)) 573 break; 574 } 575 envp_init[i] = param; 576 } else { 577 /* Command line option */ 578 unsigned int i; 579 for (i = 0; argv_init[i]; i++) { 580 if (i == MAX_INIT_ARGS) { 581 panic_later = "init"; 582 panic_param = param; 583 } 584 } 585 argv_init[i] = param; 586 } 587 return 0; 588 } 589 590 static int __init init_setup(char *str) 591 { 592 unsigned int i; 593 594 execute_command = str; 595 /* 596 * In case LILO is going to boot us with default command line, 597 * it prepends "auto" before the whole cmdline which makes 598 * the shell think it should execute a script with such name. 599 * So we ignore all arguments entered _before_ init=... [MJ] 600 */ 601 for (i = 1; i < MAX_INIT_ARGS; i++) 602 argv_init[i] = NULL; 603 return 1; 604 } 605 __setup("init=", init_setup); 606 607 static int __init rdinit_setup(char *str) 608 { 609 unsigned int i; 610 611 ramdisk_execute_command = str; 612 /* See "auto" comment in init_setup */ 613 for (i = 1; i < MAX_INIT_ARGS; i++) 614 argv_init[i] = NULL; 615 return 1; 616 } 617 __setup("rdinit=", rdinit_setup); 618 619 #ifndef CONFIG_SMP 620 static inline void setup_nr_cpu_ids(void) { } 621 static inline void smp_prepare_cpus(unsigned int maxcpus) { } 622 #endif 623 624 /* 625 * We need to store the untouched command line for future reference. 626 * We also need to store the touched command line since the parameter 627 * parsing is performed in place, and we should allow a component to 628 * store reference of name/value for future reference. 629 */ 630 static void __init setup_command_line(char *command_line) 631 { 632 size_t len, xlen = 0, ilen = 0; 633 634 if (extra_command_line) 635 xlen = strlen(extra_command_line); 636 if (extra_init_args) 637 ilen = strlen(extra_init_args) + 4; /* for " -- " */ 638 639 len = xlen + strlen(boot_command_line) + 1; 640 641 saved_command_line = memblock_alloc(len + ilen, SMP_CACHE_BYTES); 642 if (!saved_command_line) 643 panic("%s: Failed to allocate %zu bytes\n", __func__, len + ilen); 644 645 static_command_line = memblock_alloc(len, SMP_CACHE_BYTES); 646 if (!static_command_line) 647 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 648 649 if (xlen) { 650 /* 651 * We have to put extra_command_line before boot command 652 * lines because there could be dashes (separator of init 653 * command line) in the command lines. 654 */ 655 strcpy(saved_command_line, extra_command_line); 656 strcpy(static_command_line, extra_command_line); 657 } 658 strcpy(saved_command_line + xlen, boot_command_line); 659 strcpy(static_command_line + xlen, command_line); 660 661 if (ilen) { 662 /* 663 * Append supplemental init boot args to saved_command_line 664 * so that user can check what command line options passed 665 * to init. 666 * The order should always be 667 * " -- "[bootconfig init-param][cmdline init-param] 668 */ 669 if (initargs_offs) { 670 len = xlen + initargs_offs; 671 strcpy(saved_command_line + len, extra_init_args); 672 len += ilen - 4; /* strlen(extra_init_args) */ 673 strcpy(saved_command_line + len, 674 boot_command_line + initargs_offs - 1); 675 } else { 676 len = strlen(saved_command_line); 677 strcpy(saved_command_line + len, " -- "); 678 len += 4; 679 strcpy(saved_command_line + len, extra_init_args); 680 } 681 } 682 683 saved_command_line_len = strlen(saved_command_line); 684 } 685 686 /* 687 * We need to finalize in a non-__init function or else race conditions 688 * between the root thread and the init thread may cause start_kernel to 689 * be reaped by free_initmem before the root thread has proceeded to 690 * cpu_idle. 691 * 692 * gcc-3.4 accidentally inlines this function, so use noinline. 693 */ 694 695 static __initdata DECLARE_COMPLETION(kthreadd_done); 696 697 static noinline void __ref __noreturn rest_init(void) 698 { 699 struct task_struct *tsk; 700 int pid; 701 702 rcu_scheduler_starting(); 703 /* 704 * We need to spawn init first so that it obtains pid 1, however 705 * the init task will end up wanting to create kthreads, which, if 706 * we schedule it before we create kthreadd, will OOPS. 707 */ 708 pid = user_mode_thread(kernel_init, NULL, CLONE_FS); 709 /* 710 * Pin init on the boot CPU. Task migration is not properly working 711 * until sched_init_smp() has been run. It will set the allowed 712 * CPUs for init to the non isolated CPUs. 713 */ 714 rcu_read_lock(); 715 tsk = find_task_by_pid_ns(pid, &init_pid_ns); 716 tsk->flags |= PF_NO_SETAFFINITY; 717 set_cpus_allowed_ptr(tsk, cpumask_of(smp_processor_id())); 718 rcu_read_unlock(); 719 720 numa_default_policy(); 721 pid = kernel_thread(kthreadd, NULL, NULL, CLONE_FS | CLONE_FILES); 722 rcu_read_lock(); 723 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns); 724 rcu_read_unlock(); 725 726 /* 727 * Enable might_sleep() and smp_processor_id() checks. 728 * They cannot be enabled earlier because with CONFIG_PREEMPTION=y 729 * kernel_thread() would trigger might_sleep() splats. With 730 * CONFIG_PREEMPT_VOLUNTARY=y the init task might have scheduled 731 * already, but it's stuck on the kthreadd_done completion. 732 */ 733 system_state = SYSTEM_SCHEDULING; 734 735 complete(&kthreadd_done); 736 737 /* 738 * The boot idle thread must execute schedule() 739 * at least once to get things moving: 740 */ 741 schedule_preempt_disabled(); 742 /* Call into cpu_idle with preempt disabled */ 743 cpu_startup_entry(CPUHP_ONLINE); 744 } 745 746 /* Check for early params. */ 747 static int __init do_early_param(char *param, char *val, 748 const char *unused, void *arg) 749 { 750 const struct obs_kernel_param *p; 751 752 for (p = __setup_start; p < __setup_end; p++) { 753 if ((p->early && parameq(param, p->str)) || 754 (strcmp(param, "console") == 0 && 755 strcmp(p->str, "earlycon") == 0) 756 ) { 757 if (p->setup_func(val) != 0) 758 pr_warn("Malformed early option '%s'\n", param); 759 } 760 } 761 /* We accept everything at this stage. */ 762 return 0; 763 } 764 765 void __init parse_early_options(char *cmdline) 766 { 767 parse_args("early options", cmdline, NULL, 0, 0, 0, NULL, 768 do_early_param); 769 } 770 771 /* Arch code calls this early on, or if not, just before other parsing. */ 772 void __init parse_early_param(void) 773 { 774 static int done __initdata; 775 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; 776 777 if (done) 778 return; 779 780 /* All fall through to do_early_param. */ 781 strscpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); 782 parse_early_options(tmp_cmdline); 783 done = 1; 784 } 785 786 void __init __weak arch_post_acpi_subsys_init(void) { } 787 788 void __init __weak smp_setup_processor_id(void) 789 { 790 } 791 792 void __init __weak smp_prepare_boot_cpu(void) 793 { 794 } 795 796 # if THREAD_SIZE >= PAGE_SIZE 797 void __init __weak thread_stack_cache_init(void) 798 { 799 } 800 #endif 801 802 void __init __weak poking_init(void) { } 803 804 void __init __weak pgtable_cache_init(void) { } 805 806 void __init __weak trap_init(void) { } 807 808 bool initcall_debug; 809 core_param(initcall_debug, initcall_debug, bool, 0644); 810 811 #ifdef TRACEPOINTS_ENABLED 812 static void __init initcall_debug_enable(void); 813 #else 814 static inline void initcall_debug_enable(void) 815 { 816 } 817 #endif 818 819 #ifdef CONFIG_RANDOMIZE_KSTACK_OFFSET 820 DEFINE_STATIC_KEY_MAYBE_RO(CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT, 821 randomize_kstack_offset); 822 DEFINE_PER_CPU(u32, kstack_offset); 823 824 static int __init early_randomize_kstack_offset(char *buf) 825 { 826 int ret; 827 bool bool_result; 828 829 ret = kstrtobool(buf, &bool_result); 830 if (ret) 831 return ret; 832 833 if (bool_result) 834 static_branch_enable(&randomize_kstack_offset); 835 else 836 static_branch_disable(&randomize_kstack_offset); 837 return 0; 838 } 839 early_param("randomize_kstack_offset", early_randomize_kstack_offset); 840 #endif 841 842 static void __init print_unknown_bootoptions(void) 843 { 844 char *unknown_options; 845 char *end; 846 const char *const *p; 847 size_t len; 848 849 if (panic_later || (!argv_init[1] && !envp_init[2])) 850 return; 851 852 /* 853 * Determine how many options we have to print out, plus a space 854 * before each 855 */ 856 len = 1; /* null terminator */ 857 for (p = &argv_init[1]; *p; p++) { 858 len++; 859 len += strlen(*p); 860 } 861 for (p = &envp_init[2]; *p; p++) { 862 len++; 863 len += strlen(*p); 864 } 865 866 unknown_options = memblock_alloc(len, SMP_CACHE_BYTES); 867 if (!unknown_options) { 868 pr_err("%s: Failed to allocate %zu bytes\n", 869 __func__, len); 870 return; 871 } 872 end = unknown_options; 873 874 for (p = &argv_init[1]; *p; p++) 875 end += sprintf(end, " %s", *p); 876 for (p = &envp_init[2]; *p; p++) 877 end += sprintf(end, " %s", *p); 878 879 /* Start at unknown_options[1] to skip the initial space */ 880 pr_notice("Unknown kernel command line parameters \"%s\", will be passed to user space.\n", 881 &unknown_options[1]); 882 memblock_free(unknown_options, len); 883 } 884 885 static void __init early_numa_node_init(void) 886 { 887 #ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID 888 #ifndef cpu_to_node 889 int cpu; 890 891 /* The early_cpu_to_node() should be ready here. */ 892 for_each_possible_cpu(cpu) 893 set_cpu_numa_node(cpu, early_cpu_to_node(cpu)); 894 #endif 895 #endif 896 } 897 898 asmlinkage __visible __init __no_sanitize_address __noreturn __no_stack_protector 899 void start_kernel(void) 900 { 901 char *command_line; 902 char *after_dashes; 903 904 set_task_stack_end_magic(&init_task); 905 smp_setup_processor_id(); 906 debug_objects_early_init(); 907 init_vmlinux_build_id(); 908 909 cgroup_init_early(); 910 911 local_irq_disable(); 912 early_boot_irqs_disabled = true; 913 914 /* 915 * Interrupts are still disabled. Do necessary setups, then 916 * enable them. 917 */ 918 boot_cpu_init(); 919 page_address_init(); 920 pr_notice("%s", linux_banner); 921 early_security_init(); 922 setup_arch(&command_line); 923 setup_boot_config(); 924 setup_command_line(command_line); 925 setup_nr_cpu_ids(); 926 setup_per_cpu_areas(); 927 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */ 928 early_numa_node_init(); 929 boot_cpu_hotplug_init(); 930 931 pr_notice("Kernel command line: %s\n", saved_command_line); 932 /* parameters may set static keys */ 933 jump_label_init(); 934 parse_early_param(); 935 after_dashes = parse_args("Booting kernel", 936 static_command_line, __start___param, 937 __stop___param - __start___param, 938 -1, -1, NULL, &unknown_bootoption); 939 print_unknown_bootoptions(); 940 if (!IS_ERR_OR_NULL(after_dashes)) 941 parse_args("Setting init args", after_dashes, NULL, 0, -1, -1, 942 NULL, set_init_arg); 943 if (extra_init_args) 944 parse_args("Setting extra init args", extra_init_args, 945 NULL, 0, -1, -1, NULL, set_init_arg); 946 947 /* Architectural and non-timekeeping rng init, before allocator init */ 948 random_init_early(command_line); 949 950 /* 951 * These use large bootmem allocations and must precede 952 * initalization of page allocator 953 */ 954 setup_log_buf(0); 955 vfs_caches_init_early(); 956 sort_main_extable(); 957 trap_init(); 958 mm_core_init(); 959 poking_init(); 960 ftrace_init(); 961 962 /* trace_printk can be enabled here */ 963 early_trace_init(); 964 965 /* 966 * Set up the scheduler prior starting any interrupts (such as the 967 * timer interrupt). Full topology setup happens at smp_init() 968 * time - but meanwhile we still have a functioning scheduler. 969 */ 970 sched_init(); 971 972 if (WARN(!irqs_disabled(), 973 "Interrupts were enabled *very* early, fixing it\n")) 974 local_irq_disable(); 975 radix_tree_init(); 976 maple_tree_init(); 977 978 /* 979 * Set up housekeeping before setting up workqueues to allow the unbound 980 * workqueue to take non-housekeeping into account. 981 */ 982 housekeeping_init(); 983 984 /* 985 * Allow workqueue creation and work item queueing/cancelling 986 * early. Work item execution depends on kthreads and starts after 987 * workqueue_init(). 988 */ 989 workqueue_init_early(); 990 991 rcu_init(); 992 993 /* Trace events are available after this */ 994 trace_init(); 995 996 if (initcall_debug) 997 initcall_debug_enable(); 998 999 context_tracking_init(); 1000 /* init some links before init_ISA_irqs() */ 1001 early_irq_init(); 1002 init_IRQ(); 1003 tick_init(); 1004 rcu_init_nohz(); 1005 init_timers(); 1006 srcu_init(); 1007 hrtimers_init(); 1008 softirq_init(); 1009 timekeeping_init(); 1010 time_init(); 1011 1012 /* This must be after timekeeping is initialized */ 1013 random_init(); 1014 1015 /* These make use of the fully initialized rng */ 1016 kfence_init(); 1017 boot_init_stack_canary(); 1018 1019 perf_event_init(); 1020 profile_init(); 1021 call_function_init(); 1022 WARN(!irqs_disabled(), "Interrupts were enabled early\n"); 1023 1024 early_boot_irqs_disabled = false; 1025 local_irq_enable(); 1026 1027 kmem_cache_init_late(); 1028 1029 /* 1030 * HACK ALERT! This is early. We're enabling the console before 1031 * we've done PCI setups etc, and console_init() must be aware of 1032 * this. But we do want output early, in case something goes wrong. 1033 */ 1034 console_init(); 1035 if (panic_later) 1036 panic("Too many boot %s vars at `%s'", panic_later, 1037 panic_param); 1038 1039 lockdep_init(); 1040 1041 /* 1042 * Need to run this when irqs are enabled, because it wants 1043 * to self-test [hard/soft]-irqs on/off lock inversion bugs 1044 * too: 1045 */ 1046 locking_selftest(); 1047 1048 #ifdef CONFIG_BLK_DEV_INITRD 1049 if (initrd_start && !initrd_below_start_ok && 1050 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) { 1051 pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n", 1052 page_to_pfn(virt_to_page((void *)initrd_start)), 1053 min_low_pfn); 1054 initrd_start = 0; 1055 } 1056 #endif 1057 setup_per_cpu_pageset(); 1058 numa_policy_init(); 1059 acpi_early_init(); 1060 if (late_time_init) 1061 late_time_init(); 1062 sched_clock_init(); 1063 calibrate_delay(); 1064 1065 arch_cpu_finalize_init(); 1066 1067 pid_idr_init(); 1068 anon_vma_init(); 1069 #ifdef CONFIG_X86 1070 if (efi_enabled(EFI_RUNTIME_SERVICES)) 1071 efi_enter_virtual_mode(); 1072 #endif 1073 thread_stack_cache_init(); 1074 cred_init(); 1075 fork_init(); 1076 proc_caches_init(); 1077 uts_ns_init(); 1078 key_init(); 1079 security_init(); 1080 dbg_late_init(); 1081 net_ns_init(); 1082 vfs_caches_init(); 1083 pagecache_init(); 1084 signals_init(); 1085 seq_file_init(); 1086 proc_root_init(); 1087 nsfs_init(); 1088 pidfs_init(); 1089 cpuset_init(); 1090 cgroup_init(); 1091 taskstats_init_early(); 1092 delayacct_init(); 1093 1094 acpi_subsystem_init(); 1095 arch_post_acpi_subsys_init(); 1096 kcsan_init(); 1097 1098 /* Do the rest non-__init'ed, we're now alive */ 1099 rest_init(); 1100 1101 /* 1102 * Avoid stack canaries in callers of boot_init_stack_canary for gcc-10 1103 * and older. 1104 */ 1105 #if !__has_attribute(__no_stack_protector__) 1106 prevent_tail_call_optimization(); 1107 #endif 1108 } 1109 1110 /* Call all constructor functions linked into the kernel. */ 1111 static void __init do_ctors(void) 1112 { 1113 /* 1114 * For UML, the constructors have already been called by the 1115 * normal setup code as it's just a normal ELF binary, so we 1116 * cannot do it again - but we do need CONFIG_CONSTRUCTORS 1117 * even on UML for modules. 1118 */ 1119 #if defined(CONFIG_CONSTRUCTORS) && !defined(CONFIG_UML) 1120 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start; 1121 1122 for (; fn < (ctor_fn_t *) __ctors_end; fn++) 1123 (*fn)(); 1124 #endif 1125 } 1126 1127 #ifdef CONFIG_KALLSYMS 1128 struct blacklist_entry { 1129 struct list_head next; 1130 char *buf; 1131 }; 1132 1133 static __initdata_or_module LIST_HEAD(blacklisted_initcalls); 1134 1135 static int __init initcall_blacklist(char *str) 1136 { 1137 char *str_entry; 1138 struct blacklist_entry *entry; 1139 1140 /* str argument is a comma-separated list of functions */ 1141 do { 1142 str_entry = strsep(&str, ","); 1143 if (str_entry) { 1144 pr_debug("blacklisting initcall %s\n", str_entry); 1145 entry = memblock_alloc(sizeof(*entry), 1146 SMP_CACHE_BYTES); 1147 if (!entry) 1148 panic("%s: Failed to allocate %zu bytes\n", 1149 __func__, sizeof(*entry)); 1150 entry->buf = memblock_alloc(strlen(str_entry) + 1, 1151 SMP_CACHE_BYTES); 1152 if (!entry->buf) 1153 panic("%s: Failed to allocate %zu bytes\n", 1154 __func__, strlen(str_entry) + 1); 1155 strcpy(entry->buf, str_entry); 1156 list_add(&entry->next, &blacklisted_initcalls); 1157 } 1158 } while (str_entry); 1159 1160 return 1; 1161 } 1162 1163 static bool __init_or_module initcall_blacklisted(initcall_t fn) 1164 { 1165 struct blacklist_entry *entry; 1166 char fn_name[KSYM_SYMBOL_LEN]; 1167 unsigned long addr; 1168 1169 if (list_empty(&blacklisted_initcalls)) 1170 return false; 1171 1172 addr = (unsigned long) dereference_function_descriptor(fn); 1173 sprint_symbol_no_offset(fn_name, addr); 1174 1175 /* 1176 * fn will be "function_name [module_name]" where [module_name] is not 1177 * displayed for built-in init functions. Strip off the [module_name]. 1178 */ 1179 strreplace(fn_name, ' ', '\0'); 1180 1181 list_for_each_entry(entry, &blacklisted_initcalls, next) { 1182 if (!strcmp(fn_name, entry->buf)) { 1183 pr_debug("initcall %s blacklisted\n", fn_name); 1184 return true; 1185 } 1186 } 1187 1188 return false; 1189 } 1190 #else 1191 static int __init initcall_blacklist(char *str) 1192 { 1193 pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n"); 1194 return 0; 1195 } 1196 1197 static bool __init_or_module initcall_blacklisted(initcall_t fn) 1198 { 1199 return false; 1200 } 1201 #endif 1202 __setup("initcall_blacklist=", initcall_blacklist); 1203 1204 static __init_or_module void 1205 trace_initcall_start_cb(void *data, initcall_t fn) 1206 { 1207 ktime_t *calltime = data; 1208 1209 printk(KERN_DEBUG "calling %pS @ %i\n", fn, task_pid_nr(current)); 1210 *calltime = ktime_get(); 1211 } 1212 1213 static __init_or_module void 1214 trace_initcall_finish_cb(void *data, initcall_t fn, int ret) 1215 { 1216 ktime_t rettime, *calltime = data; 1217 1218 rettime = ktime_get(); 1219 printk(KERN_DEBUG "initcall %pS returned %d after %lld usecs\n", 1220 fn, ret, (unsigned long long)ktime_us_delta(rettime, *calltime)); 1221 } 1222 1223 static ktime_t initcall_calltime; 1224 1225 #ifdef TRACEPOINTS_ENABLED 1226 static void __init initcall_debug_enable(void) 1227 { 1228 int ret; 1229 1230 ret = register_trace_initcall_start(trace_initcall_start_cb, 1231 &initcall_calltime); 1232 ret |= register_trace_initcall_finish(trace_initcall_finish_cb, 1233 &initcall_calltime); 1234 WARN(ret, "Failed to register initcall tracepoints\n"); 1235 } 1236 # define do_trace_initcall_start trace_initcall_start 1237 # define do_trace_initcall_finish trace_initcall_finish 1238 #else 1239 static inline void do_trace_initcall_start(initcall_t fn) 1240 { 1241 if (!initcall_debug) 1242 return; 1243 trace_initcall_start_cb(&initcall_calltime, fn); 1244 } 1245 static inline void do_trace_initcall_finish(initcall_t fn, int ret) 1246 { 1247 if (!initcall_debug) 1248 return; 1249 trace_initcall_finish_cb(&initcall_calltime, fn, ret); 1250 } 1251 #endif /* !TRACEPOINTS_ENABLED */ 1252 1253 int __init_or_module do_one_initcall(initcall_t fn) 1254 { 1255 int count = preempt_count(); 1256 char msgbuf[64]; 1257 int ret; 1258 1259 if (initcall_blacklisted(fn)) 1260 return -EPERM; 1261 1262 do_trace_initcall_start(fn); 1263 ret = fn(); 1264 do_trace_initcall_finish(fn, ret); 1265 1266 msgbuf[0] = 0; 1267 1268 if (preempt_count() != count) { 1269 sprintf(msgbuf, "preemption imbalance "); 1270 preempt_count_set(count); 1271 } 1272 if (irqs_disabled()) { 1273 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf)); 1274 local_irq_enable(); 1275 } 1276 WARN(msgbuf[0], "initcall %pS returned with %s\n", fn, msgbuf); 1277 1278 add_latent_entropy(); 1279 return ret; 1280 } 1281 1282 1283 static initcall_entry_t *initcall_levels[] __initdata = { 1284 __initcall0_start, 1285 __initcall1_start, 1286 __initcall2_start, 1287 __initcall3_start, 1288 __initcall4_start, 1289 __initcall5_start, 1290 __initcall6_start, 1291 __initcall7_start, 1292 __initcall_end, 1293 }; 1294 1295 /* Keep these in sync with initcalls in include/linux/init.h */ 1296 static const char *initcall_level_names[] __initdata = { 1297 "pure", 1298 "core", 1299 "postcore", 1300 "arch", 1301 "subsys", 1302 "fs", 1303 "device", 1304 "late", 1305 }; 1306 1307 static int __init ignore_unknown_bootoption(char *param, char *val, 1308 const char *unused, void *arg) 1309 { 1310 return 0; 1311 } 1312 1313 static void __init do_initcall_level(int level, char *command_line) 1314 { 1315 initcall_entry_t *fn; 1316 1317 parse_args(initcall_level_names[level], 1318 command_line, __start___param, 1319 __stop___param - __start___param, 1320 level, level, 1321 NULL, ignore_unknown_bootoption); 1322 1323 trace_initcall_level(initcall_level_names[level]); 1324 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++) 1325 do_one_initcall(initcall_from_entry(fn)); 1326 } 1327 1328 static void __init do_initcalls(void) 1329 { 1330 int level; 1331 size_t len = saved_command_line_len + 1; 1332 char *command_line; 1333 1334 command_line = kzalloc(len, GFP_KERNEL); 1335 if (!command_line) 1336 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 1337 1338 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) { 1339 /* Parser modifies command_line, restore it each time */ 1340 strcpy(command_line, saved_command_line); 1341 do_initcall_level(level, command_line); 1342 } 1343 1344 kfree(command_line); 1345 } 1346 1347 /* 1348 * Ok, the machine is now initialized. None of the devices 1349 * have been touched yet, but the CPU subsystem is up and 1350 * running, and memory and process management works. 1351 * 1352 * Now we can finally start doing some real work.. 1353 */ 1354 static void __init do_basic_setup(void) 1355 { 1356 cpuset_init_smp(); 1357 driver_init(); 1358 init_irq_proc(); 1359 do_ctors(); 1360 do_initcalls(); 1361 } 1362 1363 static void __init do_pre_smp_initcalls(void) 1364 { 1365 initcall_entry_t *fn; 1366 1367 trace_initcall_level("early"); 1368 for (fn = __initcall_start; fn < __initcall0_start; fn++) 1369 do_one_initcall(initcall_from_entry(fn)); 1370 } 1371 1372 static int run_init_process(const char *init_filename) 1373 { 1374 const char *const *p; 1375 1376 argv_init[0] = init_filename; 1377 pr_info("Run %s as init process\n", init_filename); 1378 pr_debug(" with arguments:\n"); 1379 for (p = argv_init; *p; p++) 1380 pr_debug(" %s\n", *p); 1381 pr_debug(" with environment:\n"); 1382 for (p = envp_init; *p; p++) 1383 pr_debug(" %s\n", *p); 1384 return kernel_execve(init_filename, argv_init, envp_init); 1385 } 1386 1387 static int try_to_run_init_process(const char *init_filename) 1388 { 1389 int ret; 1390 1391 ret = run_init_process(init_filename); 1392 1393 if (ret && ret != -ENOENT) { 1394 pr_err("Starting init: %s exists but couldn't execute it (error %d)\n", 1395 init_filename, ret); 1396 } 1397 1398 return ret; 1399 } 1400 1401 static noinline void __init kernel_init_freeable(void); 1402 1403 #if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX) 1404 bool rodata_enabled __ro_after_init = true; 1405 1406 #ifndef arch_parse_debug_rodata 1407 static inline bool arch_parse_debug_rodata(char *str) { return false; } 1408 #endif 1409 1410 static int __init set_debug_rodata(char *str) 1411 { 1412 if (arch_parse_debug_rodata(str)) 1413 return 0; 1414 1415 if (str && !strcmp(str, "on")) 1416 rodata_enabled = true; 1417 else if (str && !strcmp(str, "off")) 1418 rodata_enabled = false; 1419 else 1420 pr_warn("Invalid option string for rodata: '%s'\n", str); 1421 return 0; 1422 } 1423 early_param("rodata", set_debug_rodata); 1424 #endif 1425 1426 static void mark_readonly(void) 1427 { 1428 if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX) && rodata_enabled) { 1429 /* 1430 * load_module() results in W+X mappings, which are cleaned 1431 * up with init_free_wq. Let's make sure that queued work is 1432 * flushed so that we don't hit false positives looking for 1433 * insecure pages which are W+X. 1434 */ 1435 flush_module_init_free_work(); 1436 mark_rodata_ro(); 1437 debug_checkwx(); 1438 rodata_test(); 1439 } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) { 1440 pr_info("Kernel memory protection disabled.\n"); 1441 } else if (IS_ENABLED(CONFIG_ARCH_HAS_STRICT_KERNEL_RWX)) { 1442 pr_warn("Kernel memory protection not selected by kernel config.\n"); 1443 } else { 1444 pr_warn("This architecture does not have kernel memory protection.\n"); 1445 } 1446 } 1447 1448 void __weak free_initmem(void) 1449 { 1450 free_initmem_default(POISON_FREE_INITMEM); 1451 } 1452 1453 static int __ref kernel_init(void *unused) 1454 { 1455 int ret; 1456 1457 /* 1458 * Wait until kthreadd is all set-up. 1459 */ 1460 wait_for_completion(&kthreadd_done); 1461 1462 kernel_init_freeable(); 1463 /* need to finish all async __init code before freeing the memory */ 1464 async_synchronize_full(); 1465 1466 system_state = SYSTEM_FREEING_INITMEM; 1467 kprobe_free_init_mem(); 1468 ftrace_free_init_mem(); 1469 kgdb_free_init_mem(); 1470 exit_boot_config(); 1471 free_initmem(); 1472 mark_readonly(); 1473 1474 /* 1475 * Kernel mappings are now finalized - update the userspace page-table 1476 * to finalize PTI. 1477 */ 1478 pti_finalize(); 1479 1480 system_state = SYSTEM_RUNNING; 1481 numa_default_policy(); 1482 1483 rcu_end_inkernel_boot(); 1484 1485 do_sysctl_args(); 1486 1487 if (ramdisk_execute_command) { 1488 ret = run_init_process(ramdisk_execute_command); 1489 if (!ret) 1490 return 0; 1491 pr_err("Failed to execute %s (error %d)\n", 1492 ramdisk_execute_command, ret); 1493 } 1494 1495 /* 1496 * We try each of these until one succeeds. 1497 * 1498 * The Bourne shell can be used instead of init if we are 1499 * trying to recover a really broken machine. 1500 */ 1501 if (execute_command) { 1502 ret = run_init_process(execute_command); 1503 if (!ret) 1504 return 0; 1505 panic("Requested init %s failed (error %d).", 1506 execute_command, ret); 1507 } 1508 1509 if (CONFIG_DEFAULT_INIT[0] != '\0') { 1510 ret = run_init_process(CONFIG_DEFAULT_INIT); 1511 if (ret) 1512 pr_err("Default init %s failed (error %d)\n", 1513 CONFIG_DEFAULT_INIT, ret); 1514 else 1515 return 0; 1516 } 1517 1518 if (!try_to_run_init_process("/sbin/init") || 1519 !try_to_run_init_process("/etc/init") || 1520 !try_to_run_init_process("/bin/init") || 1521 !try_to_run_init_process("/bin/sh")) 1522 return 0; 1523 1524 panic("No working init found. Try passing init= option to kernel. " 1525 "See Linux Documentation/admin-guide/init.rst for guidance."); 1526 } 1527 1528 /* Open /dev/console, for stdin/stdout/stderr, this should never fail */ 1529 void __init console_on_rootfs(void) 1530 { 1531 struct file *file = filp_open("/dev/console", O_RDWR, 0); 1532 1533 if (IS_ERR(file)) { 1534 pr_err("Warning: unable to open an initial console.\n"); 1535 return; 1536 } 1537 init_dup(file); 1538 init_dup(file); 1539 init_dup(file); 1540 fput(file); 1541 } 1542 1543 static noinline void __init kernel_init_freeable(void) 1544 { 1545 /* Now the scheduler is fully set up and can do blocking allocations */ 1546 gfp_allowed_mask = __GFP_BITS_MASK; 1547 1548 /* 1549 * init can allocate pages on any node 1550 */ 1551 set_mems_allowed(node_states[N_MEMORY]); 1552 1553 cad_pid = get_pid(task_pid(current)); 1554 1555 smp_prepare_cpus(setup_max_cpus); 1556 1557 workqueue_init(); 1558 1559 init_mm_internals(); 1560 1561 rcu_init_tasks_generic(); 1562 do_pre_smp_initcalls(); 1563 lockup_detector_init(); 1564 1565 smp_init(); 1566 sched_init_smp(); 1567 1568 workqueue_init_topology(); 1569 async_init(); 1570 padata_init(); 1571 page_alloc_init_late(); 1572 1573 do_basic_setup(); 1574 1575 kunit_run_all_tests(); 1576 1577 wait_for_initramfs(); 1578 console_on_rootfs(); 1579 1580 /* 1581 * check if there is an early userspace init. If yes, let it do all 1582 * the work 1583 */ 1584 if (init_eaccess(ramdisk_execute_command) != 0) { 1585 ramdisk_execute_command = NULL; 1586 prepare_namespace(); 1587 } 1588 1589 /* 1590 * Ok, we have completed the initial bootup, and 1591 * we're essentially up and running. Get rid of the 1592 * initmem segments and start the user-mode stuff.. 1593 * 1594 * rootfs is available now, try loading the public keys 1595 * and default modules 1596 */ 1597 1598 integrity_load_keys(); 1599 } 1600