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/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/mem_encrypt.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 <net/net_namespace.h> 104 105 #include <asm/io.h> 106 #include <asm/bugs.h> 107 #include <asm/setup.h> 108 #include <asm/sections.h> 109 #include <asm/cacheflush.h> 110 111 #define CREATE_TRACE_POINTS 112 #include <trace/events/initcall.h> 113 114 #include <kunit/test.h> 115 116 static int kernel_init(void *); 117 118 extern void init_IRQ(void); 119 extern void radix_tree_init(void); 120 121 /* 122 * Debug helper: via this flag we know that we are in 'early bootup code' 123 * where only the boot processor is running with IRQ disabled. This means 124 * two things - IRQ must not be enabled before the flag is cleared and some 125 * operations which are not allowed with IRQ disabled are allowed while the 126 * flag is set. 127 */ 128 bool early_boot_irqs_disabled __read_mostly; 129 130 enum system_states system_state __read_mostly; 131 EXPORT_SYMBOL(system_state); 132 133 /* 134 * Boot command-line arguments 135 */ 136 #define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT 137 #define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT 138 139 extern void time_init(void); 140 /* Default late time init is NULL. archs can override this later. */ 141 void (*__initdata late_time_init)(void); 142 143 /* Untouched command line saved by arch-specific code. */ 144 char __initdata boot_command_line[COMMAND_LINE_SIZE]; 145 /* Untouched saved command line (eg. for /proc) */ 146 char *saved_command_line; 147 /* Command line for parameter parsing */ 148 static char *static_command_line; 149 /* Untouched extra command line */ 150 static char *extra_command_line; 151 /* Extra init arguments */ 152 static char *extra_init_args; 153 154 #ifdef CONFIG_BOOT_CONFIG 155 /* Is bootconfig on command line? */ 156 static bool bootconfig_found; 157 static size_t initargs_offs; 158 #else 159 # define bootconfig_found false 160 # define initargs_offs 0 161 #endif 162 163 static char *execute_command; 164 static char *ramdisk_execute_command = "/init"; 165 166 /* 167 * Used to generate warnings if static_key manipulation functions are used 168 * before jump_label_init is called. 169 */ 170 bool static_key_initialized __read_mostly; 171 EXPORT_SYMBOL_GPL(static_key_initialized); 172 173 /* 174 * If set, this is an indication to the drivers that reset the underlying 175 * device before going ahead with the initialization otherwise driver might 176 * rely on the BIOS and skip the reset operation. 177 * 178 * This is useful if kernel is booting in an unreliable environment. 179 * For ex. kdump situation where previous kernel has crashed, BIOS has been 180 * skipped and devices will be in unknown state. 181 */ 182 unsigned int reset_devices; 183 EXPORT_SYMBOL(reset_devices); 184 185 static int __init set_reset_devices(char *str) 186 { 187 reset_devices = 1; 188 return 1; 189 } 190 191 __setup("reset_devices", set_reset_devices); 192 193 static const char *argv_init[MAX_INIT_ARGS+2] = { "init", NULL, }; 194 const char *envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, }; 195 static const char *panic_later, *panic_param; 196 197 extern const struct obs_kernel_param __setup_start[], __setup_end[]; 198 199 static bool __init obsolete_checksetup(char *line) 200 { 201 const struct obs_kernel_param *p; 202 bool had_early_param = false; 203 204 p = __setup_start; 205 do { 206 int n = strlen(p->str); 207 if (parameqn(line, p->str, n)) { 208 if (p->early) { 209 /* Already done in parse_early_param? 210 * (Needs exact match on param part). 211 * Keep iterating, as we can have early 212 * params and __setups of same names 8( */ 213 if (line[n] == '\0' || line[n] == '=') 214 had_early_param = true; 215 } else if (!p->setup_func) { 216 pr_warn("Parameter %s is obsolete, ignored\n", 217 p->str); 218 return true; 219 } else if (p->setup_func(line + n)) 220 return true; 221 } 222 p++; 223 } while (p < __setup_end); 224 225 return had_early_param; 226 } 227 228 /* 229 * This should be approx 2 Bo*oMips to start (note initial shift), and will 230 * still work even if initially too large, it will just take slightly longer 231 */ 232 unsigned long loops_per_jiffy = (1<<12); 233 EXPORT_SYMBOL(loops_per_jiffy); 234 235 static int __init debug_kernel(char *str) 236 { 237 console_loglevel = CONSOLE_LOGLEVEL_DEBUG; 238 return 0; 239 } 240 241 static int __init quiet_kernel(char *str) 242 { 243 console_loglevel = CONSOLE_LOGLEVEL_QUIET; 244 return 0; 245 } 246 247 early_param("debug", debug_kernel); 248 early_param("quiet", quiet_kernel); 249 250 static int __init loglevel(char *str) 251 { 252 int newlevel; 253 254 /* 255 * Only update loglevel value when a correct setting was passed, 256 * to prevent blind crashes (when loglevel being set to 0) that 257 * are quite hard to debug 258 */ 259 if (get_option(&str, &newlevel)) { 260 console_loglevel = newlevel; 261 return 0; 262 } 263 264 return -EINVAL; 265 } 266 267 early_param("loglevel", loglevel); 268 269 #ifdef CONFIG_BLK_DEV_INITRD 270 static void * __init get_boot_config_from_initrd(size_t *_size) 271 { 272 u32 size, csum; 273 char *data; 274 u32 *hdr; 275 int i; 276 277 if (!initrd_end) 278 return NULL; 279 280 data = (char *)initrd_end - BOOTCONFIG_MAGIC_LEN; 281 /* 282 * Since Grub may align the size of initrd to 4, we must 283 * check the preceding 3 bytes as well. 284 */ 285 for (i = 0; i < 4; i++) { 286 if (!memcmp(data, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN)) 287 goto found; 288 data--; 289 } 290 return NULL; 291 292 found: 293 hdr = (u32 *)(data - 8); 294 size = le32_to_cpu(hdr[0]); 295 csum = le32_to_cpu(hdr[1]); 296 297 data = ((void *)hdr) - size; 298 if ((unsigned long)data < initrd_start) { 299 pr_err("bootconfig size %d is greater than initrd size %ld\n", 300 size, initrd_end - initrd_start); 301 return NULL; 302 } 303 304 if (xbc_calc_checksum(data, size) != csum) { 305 pr_err("bootconfig checksum failed\n"); 306 return NULL; 307 } 308 309 /* Remove bootconfig from initramfs/initrd */ 310 initrd_end = (unsigned long)data; 311 if (_size) 312 *_size = size; 313 314 return data; 315 } 316 #else 317 static void * __init get_boot_config_from_initrd(size_t *_size) 318 { 319 return NULL; 320 } 321 #endif 322 323 #ifdef CONFIG_BOOT_CONFIG 324 325 static char xbc_namebuf[XBC_KEYLEN_MAX] __initdata; 326 327 #define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0) 328 329 static int __init xbc_snprint_cmdline(char *buf, size_t size, 330 struct xbc_node *root) 331 { 332 struct xbc_node *knode, *vnode; 333 char *end = buf + size; 334 const char *val; 335 int ret; 336 337 xbc_node_for_each_key_value(root, knode, val) { 338 ret = xbc_node_compose_key_after(root, knode, 339 xbc_namebuf, XBC_KEYLEN_MAX); 340 if (ret < 0) 341 return ret; 342 343 vnode = xbc_node_get_child(knode); 344 if (!vnode) { 345 ret = snprintf(buf, rest(buf, end), "%s ", xbc_namebuf); 346 if (ret < 0) 347 return ret; 348 buf += ret; 349 continue; 350 } 351 xbc_array_for_each_value(vnode, val) { 352 ret = snprintf(buf, rest(buf, end), "%s=\"%s\" ", 353 xbc_namebuf, val); 354 if (ret < 0) 355 return ret; 356 buf += ret; 357 } 358 } 359 360 return buf - (end - size); 361 } 362 #undef rest 363 364 /* Make an extra command line under given key word */ 365 static char * __init xbc_make_cmdline(const char *key) 366 { 367 struct xbc_node *root; 368 char *new_cmdline; 369 int ret, len = 0; 370 371 root = xbc_find_node(key); 372 if (!root) 373 return NULL; 374 375 /* Count required buffer size */ 376 len = xbc_snprint_cmdline(NULL, 0, root); 377 if (len <= 0) 378 return NULL; 379 380 new_cmdline = memblock_alloc(len + 1, SMP_CACHE_BYTES); 381 if (!new_cmdline) { 382 pr_err("Failed to allocate memory for extra kernel cmdline.\n"); 383 return NULL; 384 } 385 386 ret = xbc_snprint_cmdline(new_cmdline, len + 1, root); 387 if (ret < 0 || ret > len) { 388 pr_err("Failed to print extra kernel cmdline.\n"); 389 memblock_free(new_cmdline, len + 1); 390 return NULL; 391 } 392 393 return new_cmdline; 394 } 395 396 static int __init bootconfig_params(char *param, char *val, 397 const char *unused, void *arg) 398 { 399 if (strcmp(param, "bootconfig") == 0) { 400 bootconfig_found = true; 401 } 402 return 0; 403 } 404 405 static int __init warn_bootconfig(char *str) 406 { 407 /* The 'bootconfig' has been handled by bootconfig_params(). */ 408 return 0; 409 } 410 411 static void __init setup_boot_config(void) 412 { 413 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; 414 const char *msg, *data; 415 int pos, ret; 416 size_t size; 417 char *err; 418 419 /* Cut out the bootconfig data even if we have no bootconfig option */ 420 data = get_boot_config_from_initrd(&size); 421 /* If there is no bootconfig in initrd, try embedded one. */ 422 if (!data) 423 data = xbc_get_embedded_bootconfig(&size); 424 425 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); 426 err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL, 427 bootconfig_params); 428 429 if (IS_ERR(err) || !bootconfig_found) 430 return; 431 432 /* parse_args() stops at the next param of '--' and returns an address */ 433 if (err) 434 initargs_offs = err - tmp_cmdline; 435 436 if (!data) { 437 pr_err("'bootconfig' found on command line, but no bootconfig found\n"); 438 return; 439 } 440 441 if (size >= XBC_DATA_MAX) { 442 pr_err("bootconfig size %ld greater than max size %d\n", 443 (long)size, XBC_DATA_MAX); 444 return; 445 } 446 447 ret = xbc_init(data, size, &msg, &pos); 448 if (ret < 0) { 449 if (pos < 0) 450 pr_err("Failed to init bootconfig: %s.\n", msg); 451 else 452 pr_err("Failed to parse bootconfig: %s at %d.\n", 453 msg, pos); 454 } else { 455 xbc_get_info(&ret, NULL); 456 pr_info("Load bootconfig: %ld bytes %d nodes\n", (long)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 static void __init exit_boot_config(void) 466 { 467 xbc_exit(); 468 } 469 470 #else /* !CONFIG_BOOT_CONFIG */ 471 472 static void __init setup_boot_config(void) 473 { 474 /* Remove bootconfig data from initrd */ 475 get_boot_config_from_initrd(NULL); 476 } 477 478 static int __init warn_bootconfig(char *str) 479 { 480 pr_warn("WARNING: 'bootconfig' found on the kernel command line but CONFIG_BOOT_CONFIG is not set.\n"); 481 return 0; 482 } 483 484 #define exit_boot_config() do {} while (0) 485 486 #endif /* CONFIG_BOOT_CONFIG */ 487 488 early_param("bootconfig", warn_bootconfig); 489 490 /* Change NUL term back to "=", to make "param" the whole string. */ 491 static void __init repair_env_string(char *param, char *val) 492 { 493 if (val) { 494 /* param=val or param="val"? */ 495 if (val == param+strlen(param)+1) 496 val[-1] = '='; 497 else if (val == param+strlen(param)+2) { 498 val[-2] = '='; 499 memmove(val-1, val, strlen(val)+1); 500 } else 501 BUG(); 502 } 503 } 504 505 /* Anything after -- gets handed straight to init. */ 506 static int __init set_init_arg(char *param, char *val, 507 const char *unused, void *arg) 508 { 509 unsigned int i; 510 511 if (panic_later) 512 return 0; 513 514 repair_env_string(param, val); 515 516 for (i = 0; argv_init[i]; i++) { 517 if (i == MAX_INIT_ARGS) { 518 panic_later = "init"; 519 panic_param = param; 520 return 0; 521 } 522 } 523 argv_init[i] = param; 524 return 0; 525 } 526 527 /* 528 * Unknown boot options get handed to init, unless they look like 529 * unused parameters (modprobe will find them in /proc/cmdline). 530 */ 531 static int __init unknown_bootoption(char *param, char *val, 532 const char *unused, void *arg) 533 { 534 size_t len = strlen(param); 535 536 repair_env_string(param, val); 537 538 /* Handle obsolete-style parameters */ 539 if (obsolete_checksetup(param)) 540 return 0; 541 542 /* Unused module parameter. */ 543 if (strnchr(param, len, '.')) 544 return 0; 545 546 if (panic_later) 547 return 0; 548 549 if (val) { 550 /* Environment option */ 551 unsigned int i; 552 for (i = 0; envp_init[i]; i++) { 553 if (i == MAX_INIT_ENVS) { 554 panic_later = "env"; 555 panic_param = param; 556 } 557 if (!strncmp(param, envp_init[i], len+1)) 558 break; 559 } 560 envp_init[i] = param; 561 } else { 562 /* Command line option */ 563 unsigned int i; 564 for (i = 0; argv_init[i]; i++) { 565 if (i == MAX_INIT_ARGS) { 566 panic_later = "init"; 567 panic_param = param; 568 } 569 } 570 argv_init[i] = param; 571 } 572 return 0; 573 } 574 575 static int __init init_setup(char *str) 576 { 577 unsigned int i; 578 579 execute_command = str; 580 /* 581 * In case LILO is going to boot us with default command line, 582 * it prepends "auto" before the whole cmdline which makes 583 * the shell think it should execute a script with such name. 584 * So we ignore all arguments entered _before_ init=... [MJ] 585 */ 586 for (i = 1; i < MAX_INIT_ARGS; i++) 587 argv_init[i] = NULL; 588 return 1; 589 } 590 __setup("init=", init_setup); 591 592 static int __init rdinit_setup(char *str) 593 { 594 unsigned int i; 595 596 ramdisk_execute_command = str; 597 /* See "auto" comment in init_setup */ 598 for (i = 1; i < MAX_INIT_ARGS; i++) 599 argv_init[i] = NULL; 600 return 1; 601 } 602 __setup("rdinit=", rdinit_setup); 603 604 #ifndef CONFIG_SMP 605 static const unsigned int setup_max_cpus = NR_CPUS; 606 static inline void setup_nr_cpu_ids(void) { } 607 static inline void smp_prepare_cpus(unsigned int maxcpus) { } 608 #endif 609 610 /* 611 * We need to store the untouched command line for future reference. 612 * We also need to store the touched command line since the parameter 613 * parsing is performed in place, and we should allow a component to 614 * store reference of name/value for future reference. 615 */ 616 static void __init setup_command_line(char *command_line) 617 { 618 size_t len, xlen = 0, ilen = 0; 619 620 if (extra_command_line) 621 xlen = strlen(extra_command_line); 622 if (extra_init_args) 623 ilen = strlen(extra_init_args) + 4; /* for " -- " */ 624 625 len = xlen + strlen(boot_command_line) + 1; 626 627 saved_command_line = memblock_alloc(len + ilen, SMP_CACHE_BYTES); 628 if (!saved_command_line) 629 panic("%s: Failed to allocate %zu bytes\n", __func__, len + ilen); 630 631 static_command_line = memblock_alloc(len, SMP_CACHE_BYTES); 632 if (!static_command_line) 633 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 634 635 if (xlen) { 636 /* 637 * We have to put extra_command_line before boot command 638 * lines because there could be dashes (separator of init 639 * command line) in the command lines. 640 */ 641 strcpy(saved_command_line, extra_command_line); 642 strcpy(static_command_line, extra_command_line); 643 } 644 strcpy(saved_command_line + xlen, boot_command_line); 645 strcpy(static_command_line + xlen, command_line); 646 647 if (ilen) { 648 /* 649 * Append supplemental init boot args to saved_command_line 650 * so that user can check what command line options passed 651 * to init. 652 * The order should always be 653 * " -- "[bootconfig init-param][cmdline init-param] 654 */ 655 if (initargs_offs) { 656 len = xlen + initargs_offs; 657 strcpy(saved_command_line + len, extra_init_args); 658 len += ilen - 4; /* strlen(extra_init_args) */ 659 strcpy(saved_command_line + len, 660 boot_command_line + initargs_offs - 1); 661 } else { 662 len = strlen(saved_command_line); 663 strcpy(saved_command_line + len, " -- "); 664 len += 4; 665 strcpy(saved_command_line + len, extra_init_args); 666 } 667 } 668 } 669 670 /* 671 * We need to finalize in a non-__init function or else race conditions 672 * between the root thread and the init thread may cause start_kernel to 673 * be reaped by free_initmem before the root thread has proceeded to 674 * cpu_idle. 675 * 676 * gcc-3.4 accidentally inlines this function, so use noinline. 677 */ 678 679 static __initdata DECLARE_COMPLETION(kthreadd_done); 680 681 noinline void __ref rest_init(void) 682 { 683 struct task_struct *tsk; 684 int pid; 685 686 rcu_scheduler_starting(); 687 /* 688 * We need to spawn init first so that it obtains pid 1, however 689 * the init task will end up wanting to create kthreads, which, if 690 * we schedule it before we create kthreadd, will OOPS. 691 */ 692 pid = user_mode_thread(kernel_init, NULL, CLONE_FS); 693 /* 694 * Pin init on the boot CPU. Task migration is not properly working 695 * until sched_init_smp() has been run. It will set the allowed 696 * CPUs for init to the non isolated CPUs. 697 */ 698 rcu_read_lock(); 699 tsk = find_task_by_pid_ns(pid, &init_pid_ns); 700 tsk->flags |= PF_NO_SETAFFINITY; 701 set_cpus_allowed_ptr(tsk, cpumask_of(smp_processor_id())); 702 rcu_read_unlock(); 703 704 numa_default_policy(); 705 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES); 706 rcu_read_lock(); 707 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns); 708 rcu_read_unlock(); 709 710 /* 711 * Enable might_sleep() and smp_processor_id() checks. 712 * They cannot be enabled earlier because with CONFIG_PREEMPTION=y 713 * kernel_thread() would trigger might_sleep() splats. With 714 * CONFIG_PREEMPT_VOLUNTARY=y the init task might have scheduled 715 * already, but it's stuck on the kthreadd_done completion. 716 */ 717 system_state = SYSTEM_SCHEDULING; 718 719 complete(&kthreadd_done); 720 721 /* 722 * The boot idle thread must execute schedule() 723 * at least once to get things moving: 724 */ 725 schedule_preempt_disabled(); 726 /* Call into cpu_idle with preempt disabled */ 727 cpu_startup_entry(CPUHP_ONLINE); 728 } 729 730 /* Check for early params. */ 731 static int __init do_early_param(char *param, char *val, 732 const char *unused, void *arg) 733 { 734 const struct obs_kernel_param *p; 735 736 for (p = __setup_start; p < __setup_end; p++) { 737 if ((p->early && parameq(param, p->str)) || 738 (strcmp(param, "console") == 0 && 739 strcmp(p->str, "earlycon") == 0) 740 ) { 741 if (p->setup_func(val) != 0) 742 pr_warn("Malformed early option '%s'\n", param); 743 } 744 } 745 /* We accept everything at this stage. */ 746 return 0; 747 } 748 749 void __init parse_early_options(char *cmdline) 750 { 751 parse_args("early options", cmdline, NULL, 0, 0, 0, NULL, 752 do_early_param); 753 } 754 755 /* Arch code calls this early on, or if not, just before other parsing. */ 756 void __init parse_early_param(void) 757 { 758 static int done __initdata; 759 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; 760 761 if (done) 762 return; 763 764 /* All fall through to do_early_param. */ 765 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); 766 parse_early_options(tmp_cmdline); 767 done = 1; 768 } 769 770 void __init __weak arch_post_acpi_subsys_init(void) { } 771 772 void __init __weak smp_setup_processor_id(void) 773 { 774 } 775 776 # if THREAD_SIZE >= PAGE_SIZE 777 void __init __weak thread_stack_cache_init(void) 778 { 779 } 780 #endif 781 782 void __init __weak mem_encrypt_init(void) { } 783 784 void __init __weak poking_init(void) { } 785 786 void __init __weak pgtable_cache_init(void) { } 787 788 void __init __weak trap_init(void) { } 789 790 bool initcall_debug; 791 core_param(initcall_debug, initcall_debug, bool, 0644); 792 793 #ifdef TRACEPOINTS_ENABLED 794 static void __init initcall_debug_enable(void); 795 #else 796 static inline void initcall_debug_enable(void) 797 { 798 } 799 #endif 800 801 /* Report memory auto-initialization states for this boot. */ 802 static void __init report_meminit(void) 803 { 804 const char *stack; 805 806 if (IS_ENABLED(CONFIG_INIT_STACK_ALL_PATTERN)) 807 stack = "all(pattern)"; 808 else if (IS_ENABLED(CONFIG_INIT_STACK_ALL_ZERO)) 809 stack = "all(zero)"; 810 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL)) 811 stack = "byref_all(zero)"; 812 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF)) 813 stack = "byref(zero)"; 814 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_USER)) 815 stack = "__user(zero)"; 816 else 817 stack = "off"; 818 819 pr_info("mem auto-init: stack:%s, heap alloc:%s, heap free:%s\n", 820 stack, want_init_on_alloc(GFP_KERNEL) ? "on" : "off", 821 want_init_on_free() ? "on" : "off"); 822 if (want_init_on_free()) 823 pr_info("mem auto-init: clearing system memory may take some time...\n"); 824 } 825 826 /* 827 * Set up kernel memory allocators 828 */ 829 static void __init mm_init(void) 830 { 831 /* 832 * page_ext requires contiguous pages, 833 * bigger than MAX_ORDER unless SPARSEMEM. 834 */ 835 page_ext_init_flatmem(); 836 init_mem_debugging_and_hardening(); 837 kfence_alloc_pool(); 838 report_meminit(); 839 stack_depot_early_init(); 840 mem_init(); 841 mem_init_print_info(); 842 kmem_cache_init(); 843 /* 844 * page_owner must be initialized after buddy is ready, and also after 845 * slab is ready so that stack_depot_init() works properly 846 */ 847 page_ext_init_flatmem_late(); 848 kmemleak_init(); 849 pgtable_init(); 850 debug_objects_mem_init(); 851 vmalloc_init(); 852 /* Should be run before the first non-init thread is created */ 853 init_espfix_bsp(); 854 /* Should be run after espfix64 is set up. */ 855 pti_init(); 856 } 857 858 #ifdef CONFIG_RANDOMIZE_KSTACK_OFFSET 859 DEFINE_STATIC_KEY_MAYBE_RO(CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT, 860 randomize_kstack_offset); 861 DEFINE_PER_CPU(u32, kstack_offset); 862 863 static int __init early_randomize_kstack_offset(char *buf) 864 { 865 int ret; 866 bool bool_result; 867 868 ret = kstrtobool(buf, &bool_result); 869 if (ret) 870 return ret; 871 872 if (bool_result) 873 static_branch_enable(&randomize_kstack_offset); 874 else 875 static_branch_disable(&randomize_kstack_offset); 876 return 0; 877 } 878 early_param("randomize_kstack_offset", early_randomize_kstack_offset); 879 #endif 880 881 void __init __weak arch_call_rest_init(void) 882 { 883 rest_init(); 884 } 885 886 static void __init print_unknown_bootoptions(void) 887 { 888 char *unknown_options; 889 char *end; 890 const char *const *p; 891 size_t len; 892 893 if (panic_later || (!argv_init[1] && !envp_init[2])) 894 return; 895 896 /* 897 * Determine how many options we have to print out, plus a space 898 * before each 899 */ 900 len = 1; /* null terminator */ 901 for (p = &argv_init[1]; *p; p++) { 902 len++; 903 len += strlen(*p); 904 } 905 for (p = &envp_init[2]; *p; p++) { 906 len++; 907 len += strlen(*p); 908 } 909 910 unknown_options = memblock_alloc(len, SMP_CACHE_BYTES); 911 if (!unknown_options) { 912 pr_err("%s: Failed to allocate %zu bytes\n", 913 __func__, len); 914 return; 915 } 916 end = unknown_options; 917 918 for (p = &argv_init[1]; *p; p++) 919 end += sprintf(end, " %s", *p); 920 for (p = &envp_init[2]; *p; p++) 921 end += sprintf(end, " %s", *p); 922 923 /* Start at unknown_options[1] to skip the initial space */ 924 pr_notice("Unknown kernel command line parameters \"%s\", will be passed to user space.\n", 925 &unknown_options[1]); 926 memblock_free(unknown_options, len); 927 } 928 929 asmlinkage __visible void __init __no_sanitize_address start_kernel(void) 930 { 931 char *command_line; 932 char *after_dashes; 933 934 set_task_stack_end_magic(&init_task); 935 smp_setup_processor_id(); 936 debug_objects_early_init(); 937 init_vmlinux_build_id(); 938 939 cgroup_init_early(); 940 941 local_irq_disable(); 942 early_boot_irqs_disabled = true; 943 944 /* 945 * Interrupts are still disabled. Do necessary setups, then 946 * enable them. 947 */ 948 boot_cpu_init(); 949 page_address_init(); 950 pr_notice("%s", linux_banner); 951 early_security_init(); 952 setup_arch(&command_line); 953 setup_boot_config(); 954 setup_command_line(command_line); 955 setup_nr_cpu_ids(); 956 setup_per_cpu_areas(); 957 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */ 958 boot_cpu_hotplug_init(); 959 960 build_all_zonelists(NULL); 961 page_alloc_init(); 962 963 pr_notice("Kernel command line: %s\n", saved_command_line); 964 /* parameters may set static keys */ 965 jump_label_init(); 966 parse_early_param(); 967 after_dashes = parse_args("Booting kernel", 968 static_command_line, __start___param, 969 __stop___param - __start___param, 970 -1, -1, NULL, &unknown_bootoption); 971 print_unknown_bootoptions(); 972 if (!IS_ERR_OR_NULL(after_dashes)) 973 parse_args("Setting init args", after_dashes, NULL, 0, -1, -1, 974 NULL, set_init_arg); 975 if (extra_init_args) 976 parse_args("Setting extra init args", extra_init_args, 977 NULL, 0, -1, -1, NULL, set_init_arg); 978 979 /* 980 * These use large bootmem allocations and must precede 981 * kmem_cache_init() 982 */ 983 setup_log_buf(0); 984 vfs_caches_init_early(); 985 sort_main_extable(); 986 trap_init(); 987 mm_init(); 988 989 ftrace_init(); 990 991 /* trace_printk can be enabled here */ 992 early_trace_init(); 993 994 /* 995 * Set up the scheduler prior starting any interrupts (such as the 996 * timer interrupt). Full topology setup happens at smp_init() 997 * time - but meanwhile we still have a functioning scheduler. 998 */ 999 sched_init(); 1000 1001 if (WARN(!irqs_disabled(), 1002 "Interrupts were enabled *very* early, fixing it\n")) 1003 local_irq_disable(); 1004 radix_tree_init(); 1005 1006 /* 1007 * Set up housekeeping before setting up workqueues to allow the unbound 1008 * workqueue to take non-housekeeping into account. 1009 */ 1010 housekeeping_init(); 1011 1012 /* 1013 * Allow workqueue creation and work item queueing/cancelling 1014 * early. Work item execution depends on kthreads and starts after 1015 * workqueue_init(). 1016 */ 1017 workqueue_init_early(); 1018 1019 rcu_init(); 1020 1021 /* Trace events are available after this */ 1022 trace_init(); 1023 1024 if (initcall_debug) 1025 initcall_debug_enable(); 1026 1027 context_tracking_init(); 1028 /* init some links before init_ISA_irqs() */ 1029 early_irq_init(); 1030 init_IRQ(); 1031 tick_init(); 1032 rcu_init_nohz(); 1033 init_timers(); 1034 srcu_init(); 1035 hrtimers_init(); 1036 softirq_init(); 1037 timekeeping_init(); 1038 kfence_init(); 1039 time_init(); 1040 1041 /* 1042 * For best initial stack canary entropy, prepare it after: 1043 * - setup_arch() for any UEFI RNG entropy and boot cmdline access 1044 * - timekeeping_init() for ktime entropy used in random_init() 1045 * - time_init() for making random_get_entropy() work on some platforms 1046 * - random_init() to initialize the RNG from from early entropy sources 1047 */ 1048 random_init(command_line); 1049 boot_init_stack_canary(); 1050 1051 perf_event_init(); 1052 profile_init(); 1053 call_function_init(); 1054 WARN(!irqs_disabled(), "Interrupts were enabled early\n"); 1055 1056 early_boot_irqs_disabled = false; 1057 local_irq_enable(); 1058 1059 kmem_cache_init_late(); 1060 1061 /* 1062 * HACK ALERT! This is early. We're enabling the console before 1063 * we've done PCI setups etc, and console_init() must be aware of 1064 * this. But we do want output early, in case something goes wrong. 1065 */ 1066 console_init(); 1067 if (panic_later) 1068 panic("Too many boot %s vars at `%s'", panic_later, 1069 panic_param); 1070 1071 lockdep_init(); 1072 1073 /* 1074 * Need to run this when irqs are enabled, because it wants 1075 * to self-test [hard/soft]-irqs on/off lock inversion bugs 1076 * too: 1077 */ 1078 locking_selftest(); 1079 1080 /* 1081 * This needs to be called before any devices perform DMA 1082 * operations that might use the SWIOTLB bounce buffers. It will 1083 * mark the bounce buffers as decrypted so that their usage will 1084 * not cause "plain-text" data to be decrypted when accessed. 1085 */ 1086 mem_encrypt_init(); 1087 1088 #ifdef CONFIG_BLK_DEV_INITRD 1089 if (initrd_start && !initrd_below_start_ok && 1090 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) { 1091 pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n", 1092 page_to_pfn(virt_to_page((void *)initrd_start)), 1093 min_low_pfn); 1094 initrd_start = 0; 1095 } 1096 #endif 1097 setup_per_cpu_pageset(); 1098 numa_policy_init(); 1099 acpi_early_init(); 1100 if (late_time_init) 1101 late_time_init(); 1102 sched_clock_init(); 1103 calibrate_delay(); 1104 pid_idr_init(); 1105 anon_vma_init(); 1106 #ifdef CONFIG_X86 1107 if (efi_enabled(EFI_RUNTIME_SERVICES)) 1108 efi_enter_virtual_mode(); 1109 #endif 1110 thread_stack_cache_init(); 1111 cred_init(); 1112 fork_init(); 1113 proc_caches_init(); 1114 uts_ns_init(); 1115 key_init(); 1116 security_init(); 1117 dbg_late_init(); 1118 net_ns_init(); 1119 vfs_caches_init(); 1120 pagecache_init(); 1121 signals_init(); 1122 seq_file_init(); 1123 proc_root_init(); 1124 nsfs_init(); 1125 cpuset_init(); 1126 cgroup_init(); 1127 taskstats_init_early(); 1128 delayacct_init(); 1129 1130 poking_init(); 1131 check_bugs(); 1132 1133 acpi_subsystem_init(); 1134 arch_post_acpi_subsys_init(); 1135 kcsan_init(); 1136 1137 /* Do the rest non-__init'ed, we're now alive */ 1138 arch_call_rest_init(); 1139 1140 prevent_tail_call_optimization(); 1141 } 1142 1143 /* Call all constructor functions linked into the kernel. */ 1144 static void __init do_ctors(void) 1145 { 1146 /* 1147 * For UML, the constructors have already been called by the 1148 * normal setup code as it's just a normal ELF binary, so we 1149 * cannot do it again - but we do need CONFIG_CONSTRUCTORS 1150 * even on UML for modules. 1151 */ 1152 #if defined(CONFIG_CONSTRUCTORS) && !defined(CONFIG_UML) 1153 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start; 1154 1155 for (; fn < (ctor_fn_t *) __ctors_end; fn++) 1156 (*fn)(); 1157 #endif 1158 } 1159 1160 #ifdef CONFIG_KALLSYMS 1161 struct blacklist_entry { 1162 struct list_head next; 1163 char *buf; 1164 }; 1165 1166 static __initdata_or_module LIST_HEAD(blacklisted_initcalls); 1167 1168 static int __init initcall_blacklist(char *str) 1169 { 1170 char *str_entry; 1171 struct blacklist_entry *entry; 1172 1173 /* str argument is a comma-separated list of functions */ 1174 do { 1175 str_entry = strsep(&str, ","); 1176 if (str_entry) { 1177 pr_debug("blacklisting initcall %s\n", str_entry); 1178 entry = memblock_alloc(sizeof(*entry), 1179 SMP_CACHE_BYTES); 1180 if (!entry) 1181 panic("%s: Failed to allocate %zu bytes\n", 1182 __func__, sizeof(*entry)); 1183 entry->buf = memblock_alloc(strlen(str_entry) + 1, 1184 SMP_CACHE_BYTES); 1185 if (!entry->buf) 1186 panic("%s: Failed to allocate %zu bytes\n", 1187 __func__, strlen(str_entry) + 1); 1188 strcpy(entry->buf, str_entry); 1189 list_add(&entry->next, &blacklisted_initcalls); 1190 } 1191 } while (str_entry); 1192 1193 return 1; 1194 } 1195 1196 static bool __init_or_module initcall_blacklisted(initcall_t fn) 1197 { 1198 struct blacklist_entry *entry; 1199 char fn_name[KSYM_SYMBOL_LEN]; 1200 unsigned long addr; 1201 1202 if (list_empty(&blacklisted_initcalls)) 1203 return false; 1204 1205 addr = (unsigned long) dereference_function_descriptor(fn); 1206 sprint_symbol_no_offset(fn_name, addr); 1207 1208 /* 1209 * fn will be "function_name [module_name]" where [module_name] is not 1210 * displayed for built-in init functions. Strip off the [module_name]. 1211 */ 1212 strreplace(fn_name, ' ', '\0'); 1213 1214 list_for_each_entry(entry, &blacklisted_initcalls, next) { 1215 if (!strcmp(fn_name, entry->buf)) { 1216 pr_debug("initcall %s blacklisted\n", fn_name); 1217 return true; 1218 } 1219 } 1220 1221 return false; 1222 } 1223 #else 1224 static int __init initcall_blacklist(char *str) 1225 { 1226 pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n"); 1227 return 0; 1228 } 1229 1230 static bool __init_or_module initcall_blacklisted(initcall_t fn) 1231 { 1232 return false; 1233 } 1234 #endif 1235 __setup("initcall_blacklist=", initcall_blacklist); 1236 1237 static __init_or_module void 1238 trace_initcall_start_cb(void *data, initcall_t fn) 1239 { 1240 ktime_t *calltime = (ktime_t *)data; 1241 1242 printk(KERN_DEBUG "calling %pS @ %i\n", fn, task_pid_nr(current)); 1243 *calltime = ktime_get(); 1244 } 1245 1246 static __init_or_module void 1247 trace_initcall_finish_cb(void *data, initcall_t fn, int ret) 1248 { 1249 ktime_t rettime, *calltime = (ktime_t *)data; 1250 1251 rettime = ktime_get(); 1252 printk(KERN_DEBUG "initcall %pS returned %d after %lld usecs\n", 1253 fn, ret, (unsigned long long)ktime_us_delta(rettime, *calltime)); 1254 } 1255 1256 static ktime_t initcall_calltime; 1257 1258 #ifdef TRACEPOINTS_ENABLED 1259 static void __init initcall_debug_enable(void) 1260 { 1261 int ret; 1262 1263 ret = register_trace_initcall_start(trace_initcall_start_cb, 1264 &initcall_calltime); 1265 ret |= register_trace_initcall_finish(trace_initcall_finish_cb, 1266 &initcall_calltime); 1267 WARN(ret, "Failed to register initcall tracepoints\n"); 1268 } 1269 # define do_trace_initcall_start trace_initcall_start 1270 # define do_trace_initcall_finish trace_initcall_finish 1271 #else 1272 static inline void do_trace_initcall_start(initcall_t fn) 1273 { 1274 if (!initcall_debug) 1275 return; 1276 trace_initcall_start_cb(&initcall_calltime, fn); 1277 } 1278 static inline void do_trace_initcall_finish(initcall_t fn, int ret) 1279 { 1280 if (!initcall_debug) 1281 return; 1282 trace_initcall_finish_cb(&initcall_calltime, fn, ret); 1283 } 1284 #endif /* !TRACEPOINTS_ENABLED */ 1285 1286 int __init_or_module do_one_initcall(initcall_t fn) 1287 { 1288 int count = preempt_count(); 1289 char msgbuf[64]; 1290 int ret; 1291 1292 if (initcall_blacklisted(fn)) 1293 return -EPERM; 1294 1295 do_trace_initcall_start(fn); 1296 ret = fn(); 1297 do_trace_initcall_finish(fn, ret); 1298 1299 msgbuf[0] = 0; 1300 1301 if (preempt_count() != count) { 1302 sprintf(msgbuf, "preemption imbalance "); 1303 preempt_count_set(count); 1304 } 1305 if (irqs_disabled()) { 1306 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf)); 1307 local_irq_enable(); 1308 } 1309 WARN(msgbuf[0], "initcall %pS returned with %s\n", fn, msgbuf); 1310 1311 add_latent_entropy(); 1312 return ret; 1313 } 1314 1315 1316 extern initcall_entry_t __initcall_start[]; 1317 extern initcall_entry_t __initcall0_start[]; 1318 extern initcall_entry_t __initcall1_start[]; 1319 extern initcall_entry_t __initcall2_start[]; 1320 extern initcall_entry_t __initcall3_start[]; 1321 extern initcall_entry_t __initcall4_start[]; 1322 extern initcall_entry_t __initcall5_start[]; 1323 extern initcall_entry_t __initcall6_start[]; 1324 extern initcall_entry_t __initcall7_start[]; 1325 extern initcall_entry_t __initcall_end[]; 1326 1327 static initcall_entry_t *initcall_levels[] __initdata = { 1328 __initcall0_start, 1329 __initcall1_start, 1330 __initcall2_start, 1331 __initcall3_start, 1332 __initcall4_start, 1333 __initcall5_start, 1334 __initcall6_start, 1335 __initcall7_start, 1336 __initcall_end, 1337 }; 1338 1339 /* Keep these in sync with initcalls in include/linux/init.h */ 1340 static const char *initcall_level_names[] __initdata = { 1341 "pure", 1342 "core", 1343 "postcore", 1344 "arch", 1345 "subsys", 1346 "fs", 1347 "device", 1348 "late", 1349 }; 1350 1351 static int __init ignore_unknown_bootoption(char *param, char *val, 1352 const char *unused, void *arg) 1353 { 1354 return 0; 1355 } 1356 1357 static void __init do_initcall_level(int level, char *command_line) 1358 { 1359 initcall_entry_t *fn; 1360 1361 parse_args(initcall_level_names[level], 1362 command_line, __start___param, 1363 __stop___param - __start___param, 1364 level, level, 1365 NULL, ignore_unknown_bootoption); 1366 1367 trace_initcall_level(initcall_level_names[level]); 1368 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++) 1369 do_one_initcall(initcall_from_entry(fn)); 1370 } 1371 1372 static void __init do_initcalls(void) 1373 { 1374 int level; 1375 size_t len = strlen(saved_command_line) + 1; 1376 char *command_line; 1377 1378 command_line = kzalloc(len, GFP_KERNEL); 1379 if (!command_line) 1380 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 1381 1382 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) { 1383 /* Parser modifies command_line, restore it each time */ 1384 strcpy(command_line, saved_command_line); 1385 do_initcall_level(level, command_line); 1386 } 1387 1388 kfree(command_line); 1389 } 1390 1391 /* 1392 * Ok, the machine is now initialized. None of the devices 1393 * have been touched yet, but the CPU subsystem is up and 1394 * running, and memory and process management works. 1395 * 1396 * Now we can finally start doing some real work.. 1397 */ 1398 static void __init do_basic_setup(void) 1399 { 1400 cpuset_init_smp(); 1401 driver_init(); 1402 init_irq_proc(); 1403 do_ctors(); 1404 do_initcalls(); 1405 } 1406 1407 static void __init do_pre_smp_initcalls(void) 1408 { 1409 initcall_entry_t *fn; 1410 1411 trace_initcall_level("early"); 1412 for (fn = __initcall_start; fn < __initcall0_start; fn++) 1413 do_one_initcall(initcall_from_entry(fn)); 1414 } 1415 1416 static int run_init_process(const char *init_filename) 1417 { 1418 const char *const *p; 1419 1420 argv_init[0] = init_filename; 1421 pr_info("Run %s as init process\n", init_filename); 1422 pr_debug(" with arguments:\n"); 1423 for (p = argv_init; *p; p++) 1424 pr_debug(" %s\n", *p); 1425 pr_debug(" with environment:\n"); 1426 for (p = envp_init; *p; p++) 1427 pr_debug(" %s\n", *p); 1428 return kernel_execve(init_filename, argv_init, envp_init); 1429 } 1430 1431 static int try_to_run_init_process(const char *init_filename) 1432 { 1433 int ret; 1434 1435 ret = run_init_process(init_filename); 1436 1437 if (ret && ret != -ENOENT) { 1438 pr_err("Starting init: %s exists but couldn't execute it (error %d)\n", 1439 init_filename, ret); 1440 } 1441 1442 return ret; 1443 } 1444 1445 static noinline void __init kernel_init_freeable(void); 1446 1447 #if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX) 1448 bool rodata_enabled __ro_after_init = true; 1449 1450 #ifndef arch_parse_debug_rodata 1451 static inline bool arch_parse_debug_rodata(char *str) { return false; } 1452 #endif 1453 1454 static int __init set_debug_rodata(char *str) 1455 { 1456 if (arch_parse_debug_rodata(str)) 1457 return 0; 1458 1459 if (str && !strcmp(str, "on")) 1460 rodata_enabled = true; 1461 else if (str && !strcmp(str, "off")) 1462 rodata_enabled = false; 1463 else 1464 pr_warn("Invalid option string for rodata: '%s'\n", str); 1465 return 0; 1466 } 1467 early_param("rodata", set_debug_rodata); 1468 #endif 1469 1470 #ifdef CONFIG_STRICT_KERNEL_RWX 1471 static void mark_readonly(void) 1472 { 1473 if (rodata_enabled) { 1474 /* 1475 * load_module() results in W+X mappings, which are cleaned 1476 * up with call_rcu(). Let's make sure that queued work is 1477 * flushed so that we don't hit false positives looking for 1478 * insecure pages which are W+X. 1479 */ 1480 rcu_barrier(); 1481 mark_rodata_ro(); 1482 rodata_test(); 1483 } else 1484 pr_info("Kernel memory protection disabled.\n"); 1485 } 1486 #elif defined(CONFIG_ARCH_HAS_STRICT_KERNEL_RWX) 1487 static inline void mark_readonly(void) 1488 { 1489 pr_warn("Kernel memory protection not selected by kernel config.\n"); 1490 } 1491 #else 1492 static inline void mark_readonly(void) 1493 { 1494 pr_warn("This architecture does not have kernel memory protection.\n"); 1495 } 1496 #endif 1497 1498 void __weak free_initmem(void) 1499 { 1500 free_initmem_default(POISON_FREE_INITMEM); 1501 } 1502 1503 static int __ref kernel_init(void *unused) 1504 { 1505 int ret; 1506 1507 /* 1508 * Wait until kthreadd is all set-up. 1509 */ 1510 wait_for_completion(&kthreadd_done); 1511 1512 kernel_init_freeable(); 1513 /* need to finish all async __init code before freeing the memory */ 1514 async_synchronize_full(); 1515 1516 system_state = SYSTEM_FREEING_INITMEM; 1517 kprobe_free_init_mem(); 1518 ftrace_free_init_mem(); 1519 kgdb_free_init_mem(); 1520 exit_boot_config(); 1521 free_initmem(); 1522 mark_readonly(); 1523 1524 /* 1525 * Kernel mappings are now finalized - update the userspace page-table 1526 * to finalize PTI. 1527 */ 1528 pti_finalize(); 1529 1530 system_state = SYSTEM_RUNNING; 1531 numa_default_policy(); 1532 1533 rcu_end_inkernel_boot(); 1534 1535 do_sysctl_args(); 1536 1537 if (ramdisk_execute_command) { 1538 ret = run_init_process(ramdisk_execute_command); 1539 if (!ret) 1540 return 0; 1541 pr_err("Failed to execute %s (error %d)\n", 1542 ramdisk_execute_command, ret); 1543 } 1544 1545 /* 1546 * We try each of these until one succeeds. 1547 * 1548 * The Bourne shell can be used instead of init if we are 1549 * trying to recover a really broken machine. 1550 */ 1551 if (execute_command) { 1552 ret = run_init_process(execute_command); 1553 if (!ret) 1554 return 0; 1555 panic("Requested init %s failed (error %d).", 1556 execute_command, ret); 1557 } 1558 1559 if (CONFIG_DEFAULT_INIT[0] != '\0') { 1560 ret = run_init_process(CONFIG_DEFAULT_INIT); 1561 if (ret) 1562 pr_err("Default init %s failed (error %d)\n", 1563 CONFIG_DEFAULT_INIT, ret); 1564 else 1565 return 0; 1566 } 1567 1568 if (!try_to_run_init_process("/sbin/init") || 1569 !try_to_run_init_process("/etc/init") || 1570 !try_to_run_init_process("/bin/init") || 1571 !try_to_run_init_process("/bin/sh")) 1572 return 0; 1573 1574 panic("No working init found. Try passing init= option to kernel. " 1575 "See Linux Documentation/admin-guide/init.rst for guidance."); 1576 } 1577 1578 /* Open /dev/console, for stdin/stdout/stderr, this should never fail */ 1579 void __init console_on_rootfs(void) 1580 { 1581 struct file *file = filp_open("/dev/console", O_RDWR, 0); 1582 1583 if (IS_ERR(file)) { 1584 pr_err("Warning: unable to open an initial console.\n"); 1585 return; 1586 } 1587 init_dup(file); 1588 init_dup(file); 1589 init_dup(file); 1590 fput(file); 1591 } 1592 1593 static noinline void __init kernel_init_freeable(void) 1594 { 1595 /* Now the scheduler is fully set up and can do blocking allocations */ 1596 gfp_allowed_mask = __GFP_BITS_MASK; 1597 1598 /* 1599 * init can allocate pages on any node 1600 */ 1601 set_mems_allowed(node_states[N_MEMORY]); 1602 1603 cad_pid = get_pid(task_pid(current)); 1604 1605 smp_prepare_cpus(setup_max_cpus); 1606 1607 workqueue_init(); 1608 1609 init_mm_internals(); 1610 1611 rcu_init_tasks_generic(); 1612 do_pre_smp_initcalls(); 1613 lockup_detector_init(); 1614 1615 smp_init(); 1616 sched_init_smp(); 1617 1618 padata_init(); 1619 page_alloc_init_late(); 1620 /* Initialize page ext after all struct pages are initialized. */ 1621 page_ext_init(); 1622 1623 do_basic_setup(); 1624 1625 kunit_run_all_tests(); 1626 1627 wait_for_initramfs(); 1628 console_on_rootfs(); 1629 1630 /* 1631 * check if there is an early userspace init. If yes, let it do all 1632 * the work 1633 */ 1634 if (init_eaccess(ramdisk_execute_command) != 0) { 1635 ramdisk_execute_command = NULL; 1636 prepare_namespace(); 1637 } 1638 1639 /* 1640 * Ok, we have completed the initial bootup, and 1641 * we're essentially up and running. Get rid of the 1642 * initmem segments and start the user-mode stuff.. 1643 * 1644 * rootfs is available now, try loading the public keys 1645 * and default modules 1646 */ 1647 1648 integrity_load_keys(); 1649 } 1650