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