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/vmalloc.h> 38 #include <linux/kernel_stat.h> 39 #include <linux/start_kernel.h> 40 #include <linux/security.h> 41 #include <linux/smp.h> 42 #include <linux/profile.h> 43 #include <linux/kfence.h> 44 #include <linux/rcupdate.h> 45 #include <linux/srcu.h> 46 #include <linux/moduleparam.h> 47 #include <linux/kallsyms.h> 48 #include <linux/buildid.h> 49 #include <linux/writeback.h> 50 #include <linux/cpu.h> 51 #include <linux/cpuset.h> 52 #include <linux/cgroup.h> 53 #include <linux/efi.h> 54 #include <linux/tick.h> 55 #include <linux/sched/isolation.h> 56 #include <linux/interrupt.h> 57 #include <linux/taskstats_kern.h> 58 #include <linux/delayacct.h> 59 #include <linux/unistd.h> 60 #include <linux/utsname.h> 61 #include <linux/rmap.h> 62 #include <linux/mempolicy.h> 63 #include <linux/key.h> 64 #include <linux/page_ext.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/elevator.h> 87 #include <linux/sched/clock.h> 88 #include <linux/sched/task.h> 89 #include <linux/sched/task_stack.h> 90 #include <linux/context_tracking.h> 91 #include <linux/random.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/mem_encrypt.h> 100 #include <linux/kcsan.h> 101 #include <linux/init_syscalls.h> 102 #include <linux/stackdepot.h> 103 104 #include <asm/io.h> 105 #include <asm/bugs.h> 106 #include <asm/setup.h> 107 #include <asm/sections.h> 108 #include <asm/cacheflush.h> 109 110 #define CREATE_TRACE_POINTS 111 #include <trace/events/initcall.h> 112 113 #include <kunit/test.h> 114 115 static int kernel_init(void *); 116 117 extern void init_IRQ(void); 118 extern void radix_tree_init(void); 119 120 /* 121 * Debug helper: via this flag we know that we are in 'early bootup code' 122 * where only the boot processor is running with IRQ disabled. This means 123 * two things - IRQ must not be enabled before the flag is cleared and some 124 * operations which are not allowed with IRQ disabled are allowed while the 125 * flag is set. 126 */ 127 bool early_boot_irqs_disabled __read_mostly; 128 129 enum system_states system_state __read_mostly; 130 EXPORT_SYMBOL(system_state); 131 132 /* 133 * Boot command-line arguments 134 */ 135 #define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT 136 #define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT 137 138 extern void time_init(void); 139 /* Default late time init is NULL. archs can override this later. */ 140 void (*__initdata late_time_init)(void); 141 142 /* Untouched command line saved by arch-specific code. */ 143 char __initdata boot_command_line[COMMAND_LINE_SIZE]; 144 /* Untouched saved command line (eg. for /proc) */ 145 char *saved_command_line; 146 /* Command line for parameter parsing */ 147 static char *static_command_line; 148 /* Untouched extra command line */ 149 static char *extra_command_line; 150 /* Extra init arguments */ 151 static char *extra_init_args; 152 153 #ifdef CONFIG_BOOT_CONFIG 154 /* Is bootconfig on command line? */ 155 static bool bootconfig_found; 156 static bool initargs_found; 157 #else 158 # define bootconfig_found false 159 # define initargs_found false 160 #endif 161 162 static char *execute_command; 163 static char *ramdisk_execute_command = "/init"; 164 165 /* 166 * Used to generate warnings if static_key manipulation functions are used 167 * before jump_label_init is called. 168 */ 169 bool static_key_initialized __read_mostly; 170 EXPORT_SYMBOL_GPL(static_key_initialized); 171 172 /* 173 * If set, this is an indication to the drivers that reset the underlying 174 * device before going ahead with the initialization otherwise driver might 175 * rely on the BIOS and skip the reset operation. 176 * 177 * This is useful if kernel is booting in an unreliable environment. 178 * For ex. kdump situation where previous kernel has crashed, BIOS has been 179 * skipped and devices will be in unknown state. 180 */ 181 unsigned int reset_devices; 182 EXPORT_SYMBOL(reset_devices); 183 184 static int __init set_reset_devices(char *str) 185 { 186 reset_devices = 1; 187 return 1; 188 } 189 190 __setup("reset_devices", set_reset_devices); 191 192 static const char *argv_init[MAX_INIT_ARGS+2] = { "init", NULL, }; 193 const char *envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, }; 194 static const char *panic_later, *panic_param; 195 196 extern const struct obs_kernel_param __setup_start[], __setup_end[]; 197 198 static bool __init obsolete_checksetup(char *line) 199 { 200 const struct obs_kernel_param *p; 201 bool had_early_param = false; 202 203 p = __setup_start; 204 do { 205 int n = strlen(p->str); 206 if (parameqn(line, p->str, n)) { 207 if (p->early) { 208 /* Already done in parse_early_param? 209 * (Needs exact match on param part). 210 * Keep iterating, as we can have early 211 * params and __setups of same names 8( */ 212 if (line[n] == '\0' || line[n] == '=') 213 had_early_param = true; 214 } else if (!p->setup_func) { 215 pr_warn("Parameter %s is obsolete, ignored\n", 216 p->str); 217 return true; 218 } else if (p->setup_func(line + n)) 219 return true; 220 } 221 p++; 222 } while (p < __setup_end); 223 224 return had_early_param; 225 } 226 227 /* 228 * This should be approx 2 Bo*oMips to start (note initial shift), and will 229 * still work even if initially too large, it will just take slightly longer 230 */ 231 unsigned long loops_per_jiffy = (1<<12); 232 EXPORT_SYMBOL(loops_per_jiffy); 233 234 static int __init debug_kernel(char *str) 235 { 236 console_loglevel = CONSOLE_LOGLEVEL_DEBUG; 237 return 0; 238 } 239 240 static int __init quiet_kernel(char *str) 241 { 242 console_loglevel = CONSOLE_LOGLEVEL_QUIET; 243 return 0; 244 } 245 246 early_param("debug", debug_kernel); 247 early_param("quiet", quiet_kernel); 248 249 static int __init loglevel(char *str) 250 { 251 int newlevel; 252 253 /* 254 * Only update loglevel value when a correct setting was passed, 255 * to prevent blind crashes (when loglevel being set to 0) that 256 * are quite hard to debug 257 */ 258 if (get_option(&str, &newlevel)) { 259 console_loglevel = newlevel; 260 return 0; 261 } 262 263 return -EINVAL; 264 } 265 266 early_param("loglevel", loglevel); 267 268 #ifdef CONFIG_BLK_DEV_INITRD 269 static void * __init get_boot_config_from_initrd(u32 *_size, u32 *_csum) 270 { 271 u32 size, csum; 272 char *data; 273 u32 *hdr; 274 int i; 275 276 if (!initrd_end) 277 return NULL; 278 279 data = (char *)initrd_end - BOOTCONFIG_MAGIC_LEN; 280 /* 281 * Since Grub may align the size of initrd to 4, we must 282 * check the preceding 3 bytes as well. 283 */ 284 for (i = 0; i < 4; i++) { 285 if (!memcmp(data, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN)) 286 goto found; 287 data--; 288 } 289 return NULL; 290 291 found: 292 hdr = (u32 *)(data - 8); 293 size = le32_to_cpu(hdr[0]); 294 csum = le32_to_cpu(hdr[1]); 295 296 data = ((void *)hdr) - size; 297 if ((unsigned long)data < initrd_start) { 298 pr_err("bootconfig size %d is greater than initrd size %ld\n", 299 size, initrd_end - initrd_start); 300 return NULL; 301 } 302 303 /* Remove bootconfig from initramfs/initrd */ 304 initrd_end = (unsigned long)data; 305 if (_size) 306 *_size = size; 307 if (_csum) 308 *_csum = csum; 309 310 return data; 311 } 312 #else 313 static void * __init get_boot_config_from_initrd(u32 *_size, u32 *_csum) 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; 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 ret = snprintf(buf, rest(buf, end), "%s=\"%s\" ", 349 xbc_namebuf, val); 350 if (ret < 0) 351 return ret; 352 buf += ret; 353 } 354 } 355 356 return buf - (end - size); 357 } 358 #undef rest 359 360 /* Make an extra command line under given key word */ 361 static char * __init xbc_make_cmdline(const char *key) 362 { 363 struct xbc_node *root; 364 char *new_cmdline; 365 int ret, len = 0; 366 367 root = xbc_find_node(key); 368 if (!root) 369 return NULL; 370 371 /* Count required buffer size */ 372 len = xbc_snprint_cmdline(NULL, 0, root); 373 if (len <= 0) 374 return NULL; 375 376 new_cmdline = memblock_alloc(len + 1, SMP_CACHE_BYTES); 377 if (!new_cmdline) { 378 pr_err("Failed to allocate memory for extra kernel cmdline.\n"); 379 return NULL; 380 } 381 382 ret = xbc_snprint_cmdline(new_cmdline, len + 1, root); 383 if (ret < 0 || ret > len) { 384 pr_err("Failed to print extra kernel cmdline.\n"); 385 return NULL; 386 } 387 388 return new_cmdline; 389 } 390 391 static int __init bootconfig_params(char *param, char *val, 392 const char *unused, void *arg) 393 { 394 if (strcmp(param, "bootconfig") == 0) { 395 bootconfig_found = true; 396 } 397 return 0; 398 } 399 400 static void __init setup_boot_config(void) 401 { 402 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; 403 const char *msg; 404 int pos; 405 u32 size, csum; 406 char *data, *copy, *err; 407 int ret; 408 409 /* Cut out the bootconfig data even if we have no bootconfig option */ 410 data = get_boot_config_from_initrd(&size, &csum); 411 412 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); 413 err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL, 414 bootconfig_params); 415 416 if (IS_ERR(err) || !bootconfig_found) 417 return; 418 419 /* parse_args() stops at '--' and returns an address */ 420 if (err) 421 initargs_found = true; 422 423 if (!data) { 424 pr_err("'bootconfig' found on command line, but no bootconfig found\n"); 425 return; 426 } 427 428 if (size >= XBC_DATA_MAX) { 429 pr_err("bootconfig size %d greater than max size %d\n", 430 size, XBC_DATA_MAX); 431 return; 432 } 433 434 if (xbc_calc_checksum(data, size) != csum) { 435 pr_err("bootconfig checksum failed\n"); 436 return; 437 } 438 439 copy = memblock_alloc(size + 1, SMP_CACHE_BYTES); 440 if (!copy) { 441 pr_err("Failed to allocate memory for bootconfig\n"); 442 return; 443 } 444 445 memcpy(copy, data, size); 446 copy[size] = '\0'; 447 448 ret = xbc_init(copy, &msg, &pos); 449 if (ret < 0) { 450 if (pos < 0) 451 pr_err("Failed to init bootconfig: %s.\n", msg); 452 else 453 pr_err("Failed to parse bootconfig: %s at %d.\n", 454 msg, pos); 455 } else { 456 pr_info("Load bootconfig: %d bytes %d nodes\n", size, ret); 457 /* keys starting with "kernel." are passed via cmdline */ 458 extra_command_line = xbc_make_cmdline("kernel"); 459 /* Also, "init." keys are init arguments */ 460 extra_init_args = xbc_make_cmdline("init"); 461 } 462 return; 463 } 464 465 #else 466 467 static void __init setup_boot_config(void) 468 { 469 /* Remove bootconfig data from initrd */ 470 get_boot_config_from_initrd(NULL, NULL); 471 } 472 473 static int __init warn_bootconfig(char *str) 474 { 475 pr_warn("WARNING: 'bootconfig' found on the kernel command line but CONFIG_BOOT_CONFIG is not set.\n"); 476 return 0; 477 } 478 early_param("bootconfig", warn_bootconfig); 479 480 #endif 481 482 /* Change NUL term back to "=", to make "param" the whole string. */ 483 static void __init repair_env_string(char *param, char *val) 484 { 485 if (val) { 486 /* param=val or param="val"? */ 487 if (val == param+strlen(param)+1) 488 val[-1] = '='; 489 else if (val == param+strlen(param)+2) { 490 val[-2] = '='; 491 memmove(val-1, val, strlen(val)+1); 492 } else 493 BUG(); 494 } 495 } 496 497 /* Anything after -- gets handed straight to init. */ 498 static int __init set_init_arg(char *param, char *val, 499 const char *unused, void *arg) 500 { 501 unsigned int i; 502 503 if (panic_later) 504 return 0; 505 506 repair_env_string(param, val); 507 508 for (i = 0; argv_init[i]; i++) { 509 if (i == MAX_INIT_ARGS) { 510 panic_later = "init"; 511 panic_param = param; 512 return 0; 513 } 514 } 515 argv_init[i] = param; 516 return 0; 517 } 518 519 /* 520 * Unknown boot options get handed to init, unless they look like 521 * unused parameters (modprobe will find them in /proc/cmdline). 522 */ 523 static int __init unknown_bootoption(char *param, char *val, 524 const char *unused, void *arg) 525 { 526 size_t len = strlen(param); 527 528 repair_env_string(param, val); 529 530 /* Handle obsolete-style parameters */ 531 if (obsolete_checksetup(param)) 532 return 0; 533 534 /* Unused module parameter. */ 535 if (strnchr(param, len, '.')) 536 return 0; 537 538 if (panic_later) 539 return 0; 540 541 if (val) { 542 /* Environment option */ 543 unsigned int i; 544 for (i = 0; envp_init[i]; i++) { 545 if (i == MAX_INIT_ENVS) { 546 panic_later = "env"; 547 panic_param = param; 548 } 549 if (!strncmp(param, envp_init[i], len+1)) 550 break; 551 } 552 envp_init[i] = param; 553 } else { 554 /* Command line option */ 555 unsigned int i; 556 for (i = 0; argv_init[i]; i++) { 557 if (i == MAX_INIT_ARGS) { 558 panic_later = "init"; 559 panic_param = param; 560 } 561 } 562 argv_init[i] = param; 563 } 564 return 0; 565 } 566 567 static int __init init_setup(char *str) 568 { 569 unsigned int i; 570 571 execute_command = str; 572 /* 573 * In case LILO is going to boot us with default command line, 574 * it prepends "auto" before the whole cmdline which makes 575 * the shell think it should execute a script with such name. 576 * So we ignore all arguments entered _before_ init=... [MJ] 577 */ 578 for (i = 1; i < MAX_INIT_ARGS; i++) 579 argv_init[i] = NULL; 580 return 1; 581 } 582 __setup("init=", init_setup); 583 584 static int __init rdinit_setup(char *str) 585 { 586 unsigned int i; 587 588 ramdisk_execute_command = str; 589 /* See "auto" comment in init_setup */ 590 for (i = 1; i < MAX_INIT_ARGS; i++) 591 argv_init[i] = NULL; 592 return 1; 593 } 594 __setup("rdinit=", rdinit_setup); 595 596 #ifndef CONFIG_SMP 597 static const unsigned int setup_max_cpus = NR_CPUS; 598 static inline void setup_nr_cpu_ids(void) { } 599 static inline void smp_prepare_cpus(unsigned int maxcpus) { } 600 #endif 601 602 /* 603 * We need to store the untouched command line for future reference. 604 * We also need to store the touched command line since the parameter 605 * parsing is performed in place, and we should allow a component to 606 * store reference of name/value for future reference. 607 */ 608 static void __init setup_command_line(char *command_line) 609 { 610 size_t len, xlen = 0, ilen = 0; 611 612 if (extra_command_line) 613 xlen = strlen(extra_command_line); 614 if (extra_init_args) 615 ilen = strlen(extra_init_args) + 4; /* for " -- " */ 616 617 len = xlen + strlen(boot_command_line) + 1; 618 619 saved_command_line = memblock_alloc(len + ilen, SMP_CACHE_BYTES); 620 if (!saved_command_line) 621 panic("%s: Failed to allocate %zu bytes\n", __func__, len + ilen); 622 623 static_command_line = memblock_alloc(len, SMP_CACHE_BYTES); 624 if (!static_command_line) 625 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 626 627 if (xlen) { 628 /* 629 * We have to put extra_command_line before boot command 630 * lines because there could be dashes (separator of init 631 * command line) in the command lines. 632 */ 633 strcpy(saved_command_line, extra_command_line); 634 strcpy(static_command_line, extra_command_line); 635 } 636 strcpy(saved_command_line + xlen, boot_command_line); 637 strcpy(static_command_line + xlen, command_line); 638 639 if (ilen) { 640 /* 641 * Append supplemental init boot args to saved_command_line 642 * so that user can check what command line options passed 643 * to init. 644 */ 645 len = strlen(saved_command_line); 646 if (initargs_found) { 647 saved_command_line[len++] = ' '; 648 } else { 649 strcpy(saved_command_line + len, " -- "); 650 len += 4; 651 } 652 653 strcpy(saved_command_line + len, extra_init_args); 654 } 655 } 656 657 /* 658 * We need to finalize in a non-__init function or else race conditions 659 * between the root thread and the init thread may cause start_kernel to 660 * be reaped by free_initmem before the root thread has proceeded to 661 * cpu_idle. 662 * 663 * gcc-3.4 accidentally inlines this function, so use noinline. 664 */ 665 666 static __initdata DECLARE_COMPLETION(kthreadd_done); 667 668 noinline void __ref rest_init(void) 669 { 670 struct task_struct *tsk; 671 int pid; 672 673 rcu_scheduler_starting(); 674 /* 675 * We need to spawn init first so that it obtains pid 1, however 676 * the init task will end up wanting to create kthreads, which, if 677 * we schedule it before we create kthreadd, will OOPS. 678 */ 679 pid = kernel_thread(kernel_init, NULL, CLONE_FS); 680 /* 681 * Pin init on the boot CPU. Task migration is not properly working 682 * until sched_init_smp() has been run. It will set the allowed 683 * CPUs for init to the non isolated CPUs. 684 */ 685 rcu_read_lock(); 686 tsk = find_task_by_pid_ns(pid, &init_pid_ns); 687 tsk->flags |= PF_NO_SETAFFINITY; 688 set_cpus_allowed_ptr(tsk, cpumask_of(smp_processor_id())); 689 rcu_read_unlock(); 690 691 numa_default_policy(); 692 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES); 693 rcu_read_lock(); 694 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns); 695 rcu_read_unlock(); 696 697 /* 698 * Enable might_sleep() and smp_processor_id() checks. 699 * They cannot be enabled earlier because with CONFIG_PREEMPTION=y 700 * kernel_thread() would trigger might_sleep() splats. With 701 * CONFIG_PREEMPT_VOLUNTARY=y the init task might have scheduled 702 * already, but it's stuck on the kthreadd_done completion. 703 */ 704 system_state = SYSTEM_SCHEDULING; 705 706 complete(&kthreadd_done); 707 708 /* 709 * The boot idle thread must execute schedule() 710 * at least once to get things moving: 711 */ 712 schedule_preempt_disabled(); 713 /* Call into cpu_idle with preempt disabled */ 714 cpu_startup_entry(CPUHP_ONLINE); 715 } 716 717 /* Check for early params. */ 718 static int __init do_early_param(char *param, char *val, 719 const char *unused, void *arg) 720 { 721 const struct obs_kernel_param *p; 722 723 for (p = __setup_start; p < __setup_end; p++) { 724 if ((p->early && parameq(param, p->str)) || 725 (strcmp(param, "console") == 0 && 726 strcmp(p->str, "earlycon") == 0) 727 ) { 728 if (p->setup_func(val) != 0) 729 pr_warn("Malformed early option '%s'\n", param); 730 } 731 } 732 /* We accept everything at this stage. */ 733 return 0; 734 } 735 736 void __init parse_early_options(char *cmdline) 737 { 738 parse_args("early options", cmdline, NULL, 0, 0, 0, NULL, 739 do_early_param); 740 } 741 742 /* Arch code calls this early on, or if not, just before other parsing. */ 743 void __init parse_early_param(void) 744 { 745 static int done __initdata; 746 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; 747 748 if (done) 749 return; 750 751 /* All fall through to do_early_param. */ 752 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); 753 parse_early_options(tmp_cmdline); 754 done = 1; 755 } 756 757 void __init __weak arch_post_acpi_subsys_init(void) { } 758 759 void __init __weak smp_setup_processor_id(void) 760 { 761 } 762 763 # if THREAD_SIZE >= PAGE_SIZE 764 void __init __weak thread_stack_cache_init(void) 765 { 766 } 767 #endif 768 769 void __init __weak mem_encrypt_init(void) { } 770 771 void __init __weak poking_init(void) { } 772 773 void __init __weak pgtable_cache_init(void) { } 774 775 bool initcall_debug; 776 core_param(initcall_debug, initcall_debug, bool, 0644); 777 778 #ifdef TRACEPOINTS_ENABLED 779 static void __init initcall_debug_enable(void); 780 #else 781 static inline void initcall_debug_enable(void) 782 { 783 } 784 #endif 785 786 /* Report memory auto-initialization states for this boot. */ 787 static void __init report_meminit(void) 788 { 789 const char *stack; 790 791 if (IS_ENABLED(CONFIG_INIT_STACK_ALL_PATTERN)) 792 stack = "all(pattern)"; 793 else if (IS_ENABLED(CONFIG_INIT_STACK_ALL_ZERO)) 794 stack = "all(zero)"; 795 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL)) 796 stack = "byref_all(zero)"; 797 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF)) 798 stack = "byref(zero)"; 799 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_USER)) 800 stack = "__user(zero)"; 801 else 802 stack = "off"; 803 804 pr_info("mem auto-init: stack:%s, heap alloc:%s, heap free:%s\n", 805 stack, want_init_on_alloc(GFP_KERNEL) ? "on" : "off", 806 want_init_on_free() ? "on" : "off"); 807 if (want_init_on_free()) 808 pr_info("mem auto-init: clearing system memory may take some time...\n"); 809 } 810 811 /* 812 * Set up kernel memory allocators 813 */ 814 static void __init mm_init(void) 815 { 816 /* 817 * page_ext requires contiguous pages, 818 * bigger than MAX_ORDER unless SPARSEMEM. 819 */ 820 page_ext_init_flatmem(); 821 init_mem_debugging_and_hardening(); 822 kfence_alloc_pool(); 823 report_meminit(); 824 stack_depot_init(); 825 mem_init(); 826 mem_init_print_info(); 827 /* page_owner must be initialized after buddy is ready */ 828 page_ext_init_flatmem_late(); 829 kmem_cache_init(); 830 kmemleak_init(); 831 pgtable_init(); 832 debug_objects_mem_init(); 833 vmalloc_init(); 834 /* Should be run before the first non-init thread is created */ 835 init_espfix_bsp(); 836 /* Should be run after espfix64 is set up. */ 837 pti_init(); 838 } 839 840 #ifdef CONFIG_HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 841 DEFINE_STATIC_KEY_MAYBE_RO(CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT, 842 randomize_kstack_offset); 843 DEFINE_PER_CPU(u32, kstack_offset); 844 845 static int __init early_randomize_kstack_offset(char *buf) 846 { 847 int ret; 848 bool bool_result; 849 850 ret = kstrtobool(buf, &bool_result); 851 if (ret) 852 return ret; 853 854 if (bool_result) 855 static_branch_enable(&randomize_kstack_offset); 856 else 857 static_branch_disable(&randomize_kstack_offset); 858 return 0; 859 } 860 early_param("randomize_kstack_offset", early_randomize_kstack_offset); 861 #endif 862 863 void __init __weak arch_call_rest_init(void) 864 { 865 rest_init(); 866 } 867 868 static void __init print_unknown_bootoptions(void) 869 { 870 char *unknown_options; 871 char *end; 872 const char *const *p; 873 size_t len; 874 875 if (panic_later || (!argv_init[1] && !envp_init[2])) 876 return; 877 878 /* 879 * Determine how many options we have to print out, plus a space 880 * before each 881 */ 882 len = 1; /* null terminator */ 883 for (p = &argv_init[1]; *p; p++) { 884 len++; 885 len += strlen(*p); 886 } 887 for (p = &envp_init[2]; *p; p++) { 888 len++; 889 len += strlen(*p); 890 } 891 892 unknown_options = memblock_alloc(len, SMP_CACHE_BYTES); 893 if (!unknown_options) { 894 pr_err("%s: Failed to allocate %zu bytes\n", 895 __func__, len); 896 return; 897 } 898 end = unknown_options; 899 900 for (p = &argv_init[1]; *p; p++) 901 end += sprintf(end, " %s", *p); 902 for (p = &envp_init[2]; *p; p++) 903 end += sprintf(end, " %s", *p); 904 905 pr_notice("Unknown command line parameters:%s\n", unknown_options); 906 memblock_free(__pa(unknown_options), len); 907 } 908 909 asmlinkage __visible void __init __no_sanitize_address start_kernel(void) 910 { 911 char *command_line; 912 char *after_dashes; 913 914 set_task_stack_end_magic(&init_task); 915 smp_setup_processor_id(); 916 debug_objects_early_init(); 917 init_vmlinux_build_id(); 918 919 cgroup_init_early(); 920 921 local_irq_disable(); 922 early_boot_irqs_disabled = true; 923 924 /* 925 * Interrupts are still disabled. Do necessary setups, then 926 * enable them. 927 */ 928 boot_cpu_init(); 929 page_address_init(); 930 pr_notice("%s", linux_banner); 931 early_security_init(); 932 setup_arch(&command_line); 933 setup_boot_config(); 934 setup_command_line(command_line); 935 setup_nr_cpu_ids(); 936 setup_per_cpu_areas(); 937 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */ 938 boot_cpu_hotplug_init(); 939 940 build_all_zonelists(NULL); 941 page_alloc_init(); 942 943 pr_notice("Kernel command line: %s\n", saved_command_line); 944 /* parameters may set static keys */ 945 jump_label_init(); 946 parse_early_param(); 947 after_dashes = parse_args("Booting kernel", 948 static_command_line, __start___param, 949 __stop___param - __start___param, 950 -1, -1, NULL, &unknown_bootoption); 951 print_unknown_bootoptions(); 952 if (!IS_ERR_OR_NULL(after_dashes)) 953 parse_args("Setting init args", after_dashes, NULL, 0, -1, -1, 954 NULL, set_init_arg); 955 if (extra_init_args) 956 parse_args("Setting extra init args", extra_init_args, 957 NULL, 0, -1, -1, NULL, set_init_arg); 958 959 /* 960 * These use large bootmem allocations and must precede 961 * kmem_cache_init() 962 */ 963 setup_log_buf(0); 964 vfs_caches_init_early(); 965 sort_main_extable(); 966 trap_init(); 967 mm_init(); 968 969 ftrace_init(); 970 971 /* trace_printk can be enabled here */ 972 early_trace_init(); 973 974 /* 975 * Set up the scheduler prior starting any interrupts (such as the 976 * timer interrupt). Full topology setup happens at smp_init() 977 * time - but meanwhile we still have a functioning scheduler. 978 */ 979 sched_init(); 980 981 if (WARN(!irqs_disabled(), 982 "Interrupts were enabled *very* early, fixing it\n")) 983 local_irq_disable(); 984 radix_tree_init(); 985 986 /* 987 * Set up housekeeping before setting up workqueues to allow the unbound 988 * workqueue to take non-housekeeping into account. 989 */ 990 housekeeping_init(); 991 992 /* 993 * Allow workqueue creation and work item queueing/cancelling 994 * early. Work item execution depends on kthreads and starts after 995 * workqueue_init(). 996 */ 997 workqueue_init_early(); 998 999 rcu_init(); 1000 1001 /* Trace events are available after this */ 1002 trace_init(); 1003 1004 if (initcall_debug) 1005 initcall_debug_enable(); 1006 1007 context_tracking_init(); 1008 /* init some links before init_ISA_irqs() */ 1009 early_irq_init(); 1010 init_IRQ(); 1011 tick_init(); 1012 rcu_init_nohz(); 1013 init_timers(); 1014 srcu_init(); 1015 hrtimers_init(); 1016 softirq_init(); 1017 timekeeping_init(); 1018 kfence_init(); 1019 1020 /* 1021 * For best initial stack canary entropy, prepare it after: 1022 * - setup_arch() for any UEFI RNG entropy and boot cmdline access 1023 * - timekeeping_init() for ktime entropy used in rand_initialize() 1024 * - rand_initialize() to get any arch-specific entropy like RDRAND 1025 * - add_latent_entropy() to get any latent entropy 1026 * - adding command line entropy 1027 */ 1028 rand_initialize(); 1029 add_latent_entropy(); 1030 add_device_randomness(command_line, strlen(command_line)); 1031 boot_init_stack_canary(); 1032 1033 time_init(); 1034 perf_event_init(); 1035 profile_init(); 1036 call_function_init(); 1037 WARN(!irqs_disabled(), "Interrupts were enabled early\n"); 1038 1039 early_boot_irqs_disabled = false; 1040 local_irq_enable(); 1041 1042 kmem_cache_init_late(); 1043 1044 /* 1045 * HACK ALERT! This is early. We're enabling the console before 1046 * we've done PCI setups etc, and console_init() must be aware of 1047 * this. But we do want output early, in case something goes wrong. 1048 */ 1049 console_init(); 1050 if (panic_later) 1051 panic("Too many boot %s vars at `%s'", panic_later, 1052 panic_param); 1053 1054 lockdep_init(); 1055 1056 /* 1057 * Need to run this when irqs are enabled, because it wants 1058 * to self-test [hard/soft]-irqs on/off lock inversion bugs 1059 * too: 1060 */ 1061 locking_selftest(); 1062 1063 /* 1064 * This needs to be called before any devices perform DMA 1065 * operations that might use the SWIOTLB bounce buffers. It will 1066 * mark the bounce buffers as decrypted so that their usage will 1067 * not cause "plain-text" data to be decrypted when accessed. 1068 */ 1069 mem_encrypt_init(); 1070 1071 #ifdef CONFIG_BLK_DEV_INITRD 1072 if (initrd_start && !initrd_below_start_ok && 1073 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) { 1074 pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n", 1075 page_to_pfn(virt_to_page((void *)initrd_start)), 1076 min_low_pfn); 1077 initrd_start = 0; 1078 } 1079 #endif 1080 setup_per_cpu_pageset(); 1081 numa_policy_init(); 1082 acpi_early_init(); 1083 if (late_time_init) 1084 late_time_init(); 1085 sched_clock_init(); 1086 calibrate_delay(); 1087 pid_idr_init(); 1088 anon_vma_init(); 1089 #ifdef CONFIG_X86 1090 if (efi_enabled(EFI_RUNTIME_SERVICES)) 1091 efi_enter_virtual_mode(); 1092 #endif 1093 thread_stack_cache_init(); 1094 cred_init(); 1095 fork_init(); 1096 proc_caches_init(); 1097 uts_ns_init(); 1098 key_init(); 1099 security_init(); 1100 dbg_late_init(); 1101 vfs_caches_init(); 1102 pagecache_init(); 1103 signals_init(); 1104 seq_file_init(); 1105 proc_root_init(); 1106 nsfs_init(); 1107 cpuset_init(); 1108 cgroup_init(); 1109 taskstats_init_early(); 1110 delayacct_init(); 1111 1112 poking_init(); 1113 check_bugs(); 1114 1115 acpi_subsystem_init(); 1116 arch_post_acpi_subsys_init(); 1117 kcsan_init(); 1118 1119 /* Do the rest non-__init'ed, we're now alive */ 1120 arch_call_rest_init(); 1121 1122 prevent_tail_call_optimization(); 1123 } 1124 1125 /* Call all constructor functions linked into the kernel. */ 1126 static void __init do_ctors(void) 1127 { 1128 /* 1129 * For UML, the constructors have already been called by the 1130 * normal setup code as it's just a normal ELF binary, so we 1131 * cannot do it again - but we do need CONFIG_CONSTRUCTORS 1132 * even on UML for modules. 1133 */ 1134 #if defined(CONFIG_CONSTRUCTORS) && !defined(CONFIG_UML) 1135 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start; 1136 1137 for (; fn < (ctor_fn_t *) __ctors_end; fn++) 1138 (*fn)(); 1139 #endif 1140 } 1141 1142 #ifdef CONFIG_KALLSYMS 1143 struct blacklist_entry { 1144 struct list_head next; 1145 char *buf; 1146 }; 1147 1148 static __initdata_or_module LIST_HEAD(blacklisted_initcalls); 1149 1150 static int __init initcall_blacklist(char *str) 1151 { 1152 char *str_entry; 1153 struct blacklist_entry *entry; 1154 1155 /* str argument is a comma-separated list of functions */ 1156 do { 1157 str_entry = strsep(&str, ","); 1158 if (str_entry) { 1159 pr_debug("blacklisting initcall %s\n", str_entry); 1160 entry = memblock_alloc(sizeof(*entry), 1161 SMP_CACHE_BYTES); 1162 if (!entry) 1163 panic("%s: Failed to allocate %zu bytes\n", 1164 __func__, sizeof(*entry)); 1165 entry->buf = memblock_alloc(strlen(str_entry) + 1, 1166 SMP_CACHE_BYTES); 1167 if (!entry->buf) 1168 panic("%s: Failed to allocate %zu bytes\n", 1169 __func__, strlen(str_entry) + 1); 1170 strcpy(entry->buf, str_entry); 1171 list_add(&entry->next, &blacklisted_initcalls); 1172 } 1173 } while (str_entry); 1174 1175 return 0; 1176 } 1177 1178 static bool __init_or_module initcall_blacklisted(initcall_t fn) 1179 { 1180 struct blacklist_entry *entry; 1181 char fn_name[KSYM_SYMBOL_LEN]; 1182 unsigned long addr; 1183 1184 if (list_empty(&blacklisted_initcalls)) 1185 return false; 1186 1187 addr = (unsigned long) dereference_function_descriptor(fn); 1188 sprint_symbol_no_offset(fn_name, addr); 1189 1190 /* 1191 * fn will be "function_name [module_name]" where [module_name] is not 1192 * displayed for built-in init functions. Strip off the [module_name]. 1193 */ 1194 strreplace(fn_name, ' ', '\0'); 1195 1196 list_for_each_entry(entry, &blacklisted_initcalls, next) { 1197 if (!strcmp(fn_name, entry->buf)) { 1198 pr_debug("initcall %s blacklisted\n", fn_name); 1199 return true; 1200 } 1201 } 1202 1203 return false; 1204 } 1205 #else 1206 static int __init initcall_blacklist(char *str) 1207 { 1208 pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n"); 1209 return 0; 1210 } 1211 1212 static bool __init_or_module initcall_blacklisted(initcall_t fn) 1213 { 1214 return false; 1215 } 1216 #endif 1217 __setup("initcall_blacklist=", initcall_blacklist); 1218 1219 static __init_or_module void 1220 trace_initcall_start_cb(void *data, initcall_t fn) 1221 { 1222 ktime_t *calltime = (ktime_t *)data; 1223 1224 printk(KERN_DEBUG "calling %pS @ %i\n", fn, task_pid_nr(current)); 1225 *calltime = ktime_get(); 1226 } 1227 1228 static __init_or_module void 1229 trace_initcall_finish_cb(void *data, initcall_t fn, int ret) 1230 { 1231 ktime_t *calltime = (ktime_t *)data; 1232 ktime_t delta, rettime; 1233 unsigned long long duration; 1234 1235 rettime = ktime_get(); 1236 delta = ktime_sub(rettime, *calltime); 1237 duration = (unsigned long long) ktime_to_ns(delta) >> 10; 1238 printk(KERN_DEBUG "initcall %pS returned %d after %lld usecs\n", 1239 fn, ret, duration); 1240 } 1241 1242 static ktime_t initcall_calltime; 1243 1244 #ifdef TRACEPOINTS_ENABLED 1245 static void __init initcall_debug_enable(void) 1246 { 1247 int ret; 1248 1249 ret = register_trace_initcall_start(trace_initcall_start_cb, 1250 &initcall_calltime); 1251 ret |= register_trace_initcall_finish(trace_initcall_finish_cb, 1252 &initcall_calltime); 1253 WARN(ret, "Failed to register initcall tracepoints\n"); 1254 } 1255 # define do_trace_initcall_start trace_initcall_start 1256 # define do_trace_initcall_finish trace_initcall_finish 1257 #else 1258 static inline void do_trace_initcall_start(initcall_t fn) 1259 { 1260 if (!initcall_debug) 1261 return; 1262 trace_initcall_start_cb(&initcall_calltime, fn); 1263 } 1264 static inline void do_trace_initcall_finish(initcall_t fn, int ret) 1265 { 1266 if (!initcall_debug) 1267 return; 1268 trace_initcall_finish_cb(&initcall_calltime, fn, ret); 1269 } 1270 #endif /* !TRACEPOINTS_ENABLED */ 1271 1272 int __init_or_module do_one_initcall(initcall_t fn) 1273 { 1274 int count = preempt_count(); 1275 char msgbuf[64]; 1276 int ret; 1277 1278 if (initcall_blacklisted(fn)) 1279 return -EPERM; 1280 1281 do_trace_initcall_start(fn); 1282 ret = fn(); 1283 do_trace_initcall_finish(fn, ret); 1284 1285 msgbuf[0] = 0; 1286 1287 if (preempt_count() != count) { 1288 sprintf(msgbuf, "preemption imbalance "); 1289 preempt_count_set(count); 1290 } 1291 if (irqs_disabled()) { 1292 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf)); 1293 local_irq_enable(); 1294 } 1295 WARN(msgbuf[0], "initcall %pS returned with %s\n", fn, msgbuf); 1296 1297 add_latent_entropy(); 1298 return ret; 1299 } 1300 1301 1302 extern initcall_entry_t __initcall_start[]; 1303 extern initcall_entry_t __initcall0_start[]; 1304 extern initcall_entry_t __initcall1_start[]; 1305 extern initcall_entry_t __initcall2_start[]; 1306 extern initcall_entry_t __initcall3_start[]; 1307 extern initcall_entry_t __initcall4_start[]; 1308 extern initcall_entry_t __initcall5_start[]; 1309 extern initcall_entry_t __initcall6_start[]; 1310 extern initcall_entry_t __initcall7_start[]; 1311 extern initcall_entry_t __initcall_end[]; 1312 1313 static initcall_entry_t *initcall_levels[] __initdata = { 1314 __initcall0_start, 1315 __initcall1_start, 1316 __initcall2_start, 1317 __initcall3_start, 1318 __initcall4_start, 1319 __initcall5_start, 1320 __initcall6_start, 1321 __initcall7_start, 1322 __initcall_end, 1323 }; 1324 1325 /* Keep these in sync with initcalls in include/linux/init.h */ 1326 static const char *initcall_level_names[] __initdata = { 1327 "pure", 1328 "core", 1329 "postcore", 1330 "arch", 1331 "subsys", 1332 "fs", 1333 "device", 1334 "late", 1335 }; 1336 1337 static int __init ignore_unknown_bootoption(char *param, char *val, 1338 const char *unused, void *arg) 1339 { 1340 return 0; 1341 } 1342 1343 static void __init do_initcall_level(int level, char *command_line) 1344 { 1345 initcall_entry_t *fn; 1346 1347 parse_args(initcall_level_names[level], 1348 command_line, __start___param, 1349 __stop___param - __start___param, 1350 level, level, 1351 NULL, ignore_unknown_bootoption); 1352 1353 trace_initcall_level(initcall_level_names[level]); 1354 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++) 1355 do_one_initcall(initcall_from_entry(fn)); 1356 } 1357 1358 static void __init do_initcalls(void) 1359 { 1360 int level; 1361 size_t len = strlen(saved_command_line) + 1; 1362 char *command_line; 1363 1364 command_line = kzalloc(len, GFP_KERNEL); 1365 if (!command_line) 1366 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 1367 1368 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) { 1369 /* Parser modifies command_line, restore it each time */ 1370 strcpy(command_line, saved_command_line); 1371 do_initcall_level(level, command_line); 1372 } 1373 1374 kfree(command_line); 1375 } 1376 1377 /* 1378 * Ok, the machine is now initialized. None of the devices 1379 * have been touched yet, but the CPU subsystem is up and 1380 * running, and memory and process management works. 1381 * 1382 * Now we can finally start doing some real work.. 1383 */ 1384 static void __init do_basic_setup(void) 1385 { 1386 cpuset_init_smp(); 1387 driver_init(); 1388 init_irq_proc(); 1389 do_ctors(); 1390 usermodehelper_enable(); 1391 do_initcalls(); 1392 } 1393 1394 static void __init do_pre_smp_initcalls(void) 1395 { 1396 initcall_entry_t *fn; 1397 1398 trace_initcall_level("early"); 1399 for (fn = __initcall_start; fn < __initcall0_start; fn++) 1400 do_one_initcall(initcall_from_entry(fn)); 1401 } 1402 1403 static int run_init_process(const char *init_filename) 1404 { 1405 const char *const *p; 1406 1407 argv_init[0] = init_filename; 1408 pr_info("Run %s as init process\n", init_filename); 1409 pr_debug(" with arguments:\n"); 1410 for (p = argv_init; *p; p++) 1411 pr_debug(" %s\n", *p); 1412 pr_debug(" with environment:\n"); 1413 for (p = envp_init; *p; p++) 1414 pr_debug(" %s\n", *p); 1415 return kernel_execve(init_filename, argv_init, envp_init); 1416 } 1417 1418 static int try_to_run_init_process(const char *init_filename) 1419 { 1420 int ret; 1421 1422 ret = run_init_process(init_filename); 1423 1424 if (ret && ret != -ENOENT) { 1425 pr_err("Starting init: %s exists but couldn't execute it (error %d)\n", 1426 init_filename, ret); 1427 } 1428 1429 return ret; 1430 } 1431 1432 static noinline void __init kernel_init_freeable(void); 1433 1434 #if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX) 1435 bool rodata_enabled __ro_after_init = true; 1436 static int __init set_debug_rodata(char *str) 1437 { 1438 return strtobool(str, &rodata_enabled); 1439 } 1440 __setup("rodata=", set_debug_rodata); 1441 #endif 1442 1443 #ifdef CONFIG_STRICT_KERNEL_RWX 1444 static void mark_readonly(void) 1445 { 1446 if (rodata_enabled) { 1447 /* 1448 * load_module() results in W+X mappings, which are cleaned 1449 * up with call_rcu(). Let's make sure that queued work is 1450 * flushed so that we don't hit false positives looking for 1451 * insecure pages which are W+X. 1452 */ 1453 rcu_barrier(); 1454 mark_rodata_ro(); 1455 rodata_test(); 1456 } else 1457 pr_info("Kernel memory protection disabled.\n"); 1458 } 1459 #elif defined(CONFIG_ARCH_HAS_STRICT_KERNEL_RWX) 1460 static inline void mark_readonly(void) 1461 { 1462 pr_warn("Kernel memory protection not selected by kernel config.\n"); 1463 } 1464 #else 1465 static inline void mark_readonly(void) 1466 { 1467 pr_warn("This architecture does not have kernel memory protection.\n"); 1468 } 1469 #endif 1470 1471 void __weak free_initmem(void) 1472 { 1473 free_initmem_default(POISON_FREE_INITMEM); 1474 } 1475 1476 static int __ref kernel_init(void *unused) 1477 { 1478 int ret; 1479 1480 /* 1481 * Wait until kthreadd is all set-up. 1482 */ 1483 wait_for_completion(&kthreadd_done); 1484 1485 kernel_init_freeable(); 1486 /* need to finish all async __init code before freeing the memory */ 1487 async_synchronize_full(); 1488 kprobe_free_init_mem(); 1489 ftrace_free_init_mem(); 1490 kgdb_free_init_mem(); 1491 free_initmem(); 1492 mark_readonly(); 1493 1494 /* 1495 * Kernel mappings are now finalized - update the userspace page-table 1496 * to finalize PTI. 1497 */ 1498 pti_finalize(); 1499 1500 system_state = SYSTEM_RUNNING; 1501 numa_default_policy(); 1502 1503 rcu_end_inkernel_boot(); 1504 1505 do_sysctl_args(); 1506 1507 if (ramdisk_execute_command) { 1508 ret = run_init_process(ramdisk_execute_command); 1509 if (!ret) 1510 return 0; 1511 pr_err("Failed to execute %s (error %d)\n", 1512 ramdisk_execute_command, ret); 1513 } 1514 1515 /* 1516 * We try each of these until one succeeds. 1517 * 1518 * The Bourne shell can be used instead of init if we are 1519 * trying to recover a really broken machine. 1520 */ 1521 if (execute_command) { 1522 ret = run_init_process(execute_command); 1523 if (!ret) 1524 return 0; 1525 panic("Requested init %s failed (error %d).", 1526 execute_command, ret); 1527 } 1528 1529 if (CONFIG_DEFAULT_INIT[0] != '\0') { 1530 ret = run_init_process(CONFIG_DEFAULT_INIT); 1531 if (ret) 1532 pr_err("Default init %s failed (error %d)\n", 1533 CONFIG_DEFAULT_INIT, ret); 1534 else 1535 return 0; 1536 } 1537 1538 if (!try_to_run_init_process("/sbin/init") || 1539 !try_to_run_init_process("/etc/init") || 1540 !try_to_run_init_process("/bin/init") || 1541 !try_to_run_init_process("/bin/sh")) 1542 return 0; 1543 1544 panic("No working init found. Try passing init= option to kernel. " 1545 "See Linux Documentation/admin-guide/init.rst for guidance."); 1546 } 1547 1548 /* Open /dev/console, for stdin/stdout/stderr, this should never fail */ 1549 void __init console_on_rootfs(void) 1550 { 1551 struct file *file = filp_open("/dev/console", O_RDWR, 0); 1552 1553 if (IS_ERR(file)) { 1554 pr_err("Warning: unable to open an initial console.\n"); 1555 return; 1556 } 1557 init_dup(file); 1558 init_dup(file); 1559 init_dup(file); 1560 fput(file); 1561 } 1562 1563 static noinline void __init kernel_init_freeable(void) 1564 { 1565 /* Now the scheduler is fully set up and can do blocking allocations */ 1566 gfp_allowed_mask = __GFP_BITS_MASK; 1567 1568 /* 1569 * init can allocate pages on any node 1570 */ 1571 set_mems_allowed(node_states[N_MEMORY]); 1572 1573 cad_pid = get_pid(task_pid(current)); 1574 1575 smp_prepare_cpus(setup_max_cpus); 1576 1577 workqueue_init(); 1578 1579 init_mm_internals(); 1580 1581 rcu_init_tasks_generic(); 1582 do_pre_smp_initcalls(); 1583 lockup_detector_init(); 1584 1585 smp_init(); 1586 sched_init_smp(); 1587 1588 padata_init(); 1589 page_alloc_init_late(); 1590 /* Initialize page ext after all struct pages are initialized. */ 1591 page_ext_init(); 1592 1593 do_basic_setup(); 1594 1595 kunit_run_all_tests(); 1596 1597 wait_for_initramfs(); 1598 console_on_rootfs(); 1599 1600 /* 1601 * check if there is an early userspace init. If yes, let it do all 1602 * the work 1603 */ 1604 if (init_eaccess(ramdisk_execute_command) != 0) { 1605 ramdisk_execute_command = NULL; 1606 prepare_namespace(); 1607 } 1608 1609 /* 1610 * Ok, we have completed the initial bootup, and 1611 * we're essentially up and running. Get rid of the 1612 * initmem segments and start the user-mode stuff.. 1613 * 1614 * rootfs is available now, try loading the public keys 1615 * and default modules 1616 */ 1617 1618 integrity_load_keys(); 1619 } 1620