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 <net/net_namespace.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 size_t initargs_offs; 157 #else 158 # define bootconfig_found false 159 # define initargs_offs 0 160 #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(size_t *_size) 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 if (xbc_calc_checksum(data, size) != csum) { 304 pr_err("bootconfig checksum failed\n"); 305 return NULL; 306 } 307 308 /* Remove bootconfig from initramfs/initrd */ 309 initrd_end = (unsigned long)data; 310 if (_size) 311 *_size = size; 312 313 return data; 314 } 315 #else 316 static void * __init get_boot_config_from_initrd(size_t *_size) 317 { 318 return NULL; 319 } 320 #endif 321 322 #ifdef CONFIG_BOOT_CONFIG 323 324 static char xbc_namebuf[XBC_KEYLEN_MAX] __initdata; 325 326 #define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0) 327 328 static int __init xbc_snprint_cmdline(char *buf, size_t size, 329 struct xbc_node *root) 330 { 331 struct xbc_node *knode, *vnode; 332 char *end = buf + size; 333 const char *val; 334 int ret; 335 336 xbc_node_for_each_key_value(root, knode, val) { 337 ret = xbc_node_compose_key_after(root, knode, 338 xbc_namebuf, XBC_KEYLEN_MAX); 339 if (ret < 0) 340 return ret; 341 342 vnode = xbc_node_get_child(knode); 343 if (!vnode) { 344 ret = snprintf(buf, rest(buf, end), "%s ", xbc_namebuf); 345 if (ret < 0) 346 return ret; 347 buf += ret; 348 continue; 349 } 350 xbc_array_for_each_value(vnode, val) { 351 ret = snprintf(buf, rest(buf, end), "%s=\"%s\" ", 352 xbc_namebuf, val); 353 if (ret < 0) 354 return ret; 355 buf += ret; 356 } 357 } 358 359 return buf - (end - size); 360 } 361 #undef rest 362 363 /* Make an extra command line under given key word */ 364 static char * __init xbc_make_cmdline(const char *key) 365 { 366 struct xbc_node *root; 367 char *new_cmdline; 368 int ret, len = 0; 369 370 root = xbc_find_node(key); 371 if (!root) 372 return NULL; 373 374 /* Count required buffer size */ 375 len = xbc_snprint_cmdline(NULL, 0, root); 376 if (len <= 0) 377 return NULL; 378 379 new_cmdline = memblock_alloc(len + 1, SMP_CACHE_BYTES); 380 if (!new_cmdline) { 381 pr_err("Failed to allocate memory for extra kernel cmdline.\n"); 382 return NULL; 383 } 384 385 ret = xbc_snprint_cmdline(new_cmdline, len + 1, root); 386 if (ret < 0 || ret > len) { 387 pr_err("Failed to print extra kernel cmdline.\n"); 388 memblock_free(new_cmdline, len + 1); 389 return NULL; 390 } 391 392 return new_cmdline; 393 } 394 395 static int __init bootconfig_params(char *param, char *val, 396 const char *unused, void *arg) 397 { 398 if (strcmp(param, "bootconfig") == 0) { 399 bootconfig_found = true; 400 } 401 return 0; 402 } 403 404 static int __init warn_bootconfig(char *str) 405 { 406 /* The 'bootconfig' has been handled by bootconfig_params(). */ 407 return 0; 408 } 409 410 static void __init setup_boot_config(void) 411 { 412 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; 413 const char *msg, *data; 414 int pos, ret; 415 size_t size; 416 char *err; 417 418 /* Cut out the bootconfig data even if we have no bootconfig option */ 419 data = get_boot_config_from_initrd(&size); 420 /* If there is no bootconfig in initrd, try embedded one. */ 421 if (!data) 422 data = xbc_get_embedded_bootconfig(&size); 423 424 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); 425 err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL, 426 bootconfig_params); 427 428 if (IS_ERR(err) || !bootconfig_found) 429 return; 430 431 /* parse_args() stops at the next param of '--' and returns an address */ 432 if (err) 433 initargs_offs = err - tmp_cmdline; 434 435 if (!data) { 436 pr_err("'bootconfig' found on command line, but no bootconfig found\n"); 437 return; 438 } 439 440 if (size >= XBC_DATA_MAX) { 441 pr_err("bootconfig size %ld greater than max size %d\n", 442 (long)size, XBC_DATA_MAX); 443 return; 444 } 445 446 ret = xbc_init(data, size, &msg, &pos); 447 if (ret < 0) { 448 if (pos < 0) 449 pr_err("Failed to init bootconfig: %s.\n", msg); 450 else 451 pr_err("Failed to parse bootconfig: %s at %d.\n", 452 msg, pos); 453 } else { 454 xbc_get_info(&ret, NULL); 455 pr_info("Load bootconfig: %ld bytes %d nodes\n", (long)size, ret); 456 /* keys starting with "kernel." are passed via cmdline */ 457 extra_command_line = xbc_make_cmdline("kernel"); 458 /* Also, "init." keys are init arguments */ 459 extra_init_args = xbc_make_cmdline("init"); 460 } 461 return; 462 } 463 464 static void __init exit_boot_config(void) 465 { 466 xbc_exit(); 467 } 468 469 #else /* !CONFIG_BOOT_CONFIG */ 470 471 static void __init setup_boot_config(void) 472 { 473 /* Remove bootconfig data from initrd */ 474 get_boot_config_from_initrd(NULL); 475 } 476 477 static int __init warn_bootconfig(char *str) 478 { 479 pr_warn("WARNING: 'bootconfig' found on the kernel command line but CONFIG_BOOT_CONFIG is not set.\n"); 480 return 0; 481 } 482 483 #define exit_boot_config() do {} while (0) 484 485 #endif /* CONFIG_BOOT_CONFIG */ 486 487 early_param("bootconfig", warn_bootconfig); 488 489 /* Change NUL term back to "=", to make "param" the whole string. */ 490 static void __init repair_env_string(char *param, char *val) 491 { 492 if (val) { 493 /* param=val or param="val"? */ 494 if (val == param+strlen(param)+1) 495 val[-1] = '='; 496 else if (val == param+strlen(param)+2) { 497 val[-2] = '='; 498 memmove(val-1, val, strlen(val)+1); 499 } else 500 BUG(); 501 } 502 } 503 504 /* Anything after -- gets handed straight to init. */ 505 static int __init set_init_arg(char *param, char *val, 506 const char *unused, void *arg) 507 { 508 unsigned int i; 509 510 if (panic_later) 511 return 0; 512 513 repair_env_string(param, val); 514 515 for (i = 0; argv_init[i]; i++) { 516 if (i == MAX_INIT_ARGS) { 517 panic_later = "init"; 518 panic_param = param; 519 return 0; 520 } 521 } 522 argv_init[i] = param; 523 return 0; 524 } 525 526 /* 527 * Unknown boot options get handed to init, unless they look like 528 * unused parameters (modprobe will find them in /proc/cmdline). 529 */ 530 static int __init unknown_bootoption(char *param, char *val, 531 const char *unused, void *arg) 532 { 533 size_t len = strlen(param); 534 535 repair_env_string(param, val); 536 537 /* Handle obsolete-style parameters */ 538 if (obsolete_checksetup(param)) 539 return 0; 540 541 /* Unused module parameter. */ 542 if (strnchr(param, len, '.')) 543 return 0; 544 545 if (panic_later) 546 return 0; 547 548 if (val) { 549 /* Environment option */ 550 unsigned int i; 551 for (i = 0; envp_init[i]; i++) { 552 if (i == MAX_INIT_ENVS) { 553 panic_later = "env"; 554 panic_param = param; 555 } 556 if (!strncmp(param, envp_init[i], len+1)) 557 break; 558 } 559 envp_init[i] = param; 560 } else { 561 /* Command line option */ 562 unsigned int i; 563 for (i = 0; argv_init[i]; i++) { 564 if (i == MAX_INIT_ARGS) { 565 panic_later = "init"; 566 panic_param = param; 567 } 568 } 569 argv_init[i] = param; 570 } 571 return 0; 572 } 573 574 static int __init init_setup(char *str) 575 { 576 unsigned int i; 577 578 execute_command = str; 579 /* 580 * In case LILO is going to boot us with default command line, 581 * it prepends "auto" before the whole cmdline which makes 582 * the shell think it should execute a script with such name. 583 * So we ignore all arguments entered _before_ init=... [MJ] 584 */ 585 for (i = 1; i < MAX_INIT_ARGS; i++) 586 argv_init[i] = NULL; 587 return 1; 588 } 589 __setup("init=", init_setup); 590 591 static int __init rdinit_setup(char *str) 592 { 593 unsigned int i; 594 595 ramdisk_execute_command = str; 596 /* See "auto" comment in init_setup */ 597 for (i = 1; i < MAX_INIT_ARGS; i++) 598 argv_init[i] = NULL; 599 return 1; 600 } 601 __setup("rdinit=", rdinit_setup); 602 603 #ifndef CONFIG_SMP 604 static const unsigned int setup_max_cpus = NR_CPUS; 605 static inline void setup_nr_cpu_ids(void) { } 606 static inline void smp_prepare_cpus(unsigned int maxcpus) { } 607 #endif 608 609 /* 610 * We need to store the untouched command line for future reference. 611 * We also need to store the touched command line since the parameter 612 * parsing is performed in place, and we should allow a component to 613 * store reference of name/value for future reference. 614 */ 615 static void __init setup_command_line(char *command_line) 616 { 617 size_t len, xlen = 0, ilen = 0; 618 619 if (extra_command_line) 620 xlen = strlen(extra_command_line); 621 if (extra_init_args) 622 ilen = strlen(extra_init_args) + 4; /* for " -- " */ 623 624 len = xlen + strlen(boot_command_line) + 1; 625 626 saved_command_line = memblock_alloc(len + ilen, SMP_CACHE_BYTES); 627 if (!saved_command_line) 628 panic("%s: Failed to allocate %zu bytes\n", __func__, len + ilen); 629 630 static_command_line = memblock_alloc(len, SMP_CACHE_BYTES); 631 if (!static_command_line) 632 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 633 634 if (xlen) { 635 /* 636 * We have to put extra_command_line before boot command 637 * lines because there could be dashes (separator of init 638 * command line) in the command lines. 639 */ 640 strcpy(saved_command_line, extra_command_line); 641 strcpy(static_command_line, extra_command_line); 642 } 643 strcpy(saved_command_line + xlen, boot_command_line); 644 strcpy(static_command_line + xlen, command_line); 645 646 if (ilen) { 647 /* 648 * Append supplemental init boot args to saved_command_line 649 * so that user can check what command line options passed 650 * to init. 651 * The order should always be 652 * " -- "[bootconfig init-param][cmdline init-param] 653 */ 654 if (initargs_offs) { 655 len = xlen + initargs_offs; 656 strcpy(saved_command_line + len, extra_init_args); 657 len += ilen - 4; /* strlen(extra_init_args) */ 658 strcpy(saved_command_line + len, 659 boot_command_line + initargs_offs - 1); 660 } else { 661 len = strlen(saved_command_line); 662 strcpy(saved_command_line + len, " -- "); 663 len += 4; 664 strcpy(saved_command_line + len, extra_init_args); 665 } 666 } 667 } 668 669 /* 670 * We need to finalize in a non-__init function or else race conditions 671 * between the root thread and the init thread may cause start_kernel to 672 * be reaped by free_initmem before the root thread has proceeded to 673 * cpu_idle. 674 * 675 * gcc-3.4 accidentally inlines this function, so use noinline. 676 */ 677 678 static __initdata DECLARE_COMPLETION(kthreadd_done); 679 680 noinline void __ref rest_init(void) 681 { 682 struct task_struct *tsk; 683 int pid; 684 685 rcu_scheduler_starting(); 686 /* 687 * We need to spawn init first so that it obtains pid 1, however 688 * the init task will end up wanting to create kthreads, which, if 689 * we schedule it before we create kthreadd, will OOPS. 690 */ 691 pid = user_mode_thread(kernel_init, NULL, CLONE_FS); 692 /* 693 * Pin init on the boot CPU. Task migration is not properly working 694 * until sched_init_smp() has been run. It will set the allowed 695 * CPUs for init to the non isolated CPUs. 696 */ 697 rcu_read_lock(); 698 tsk = find_task_by_pid_ns(pid, &init_pid_ns); 699 tsk->flags |= PF_NO_SETAFFINITY; 700 set_cpus_allowed_ptr(tsk, cpumask_of(smp_processor_id())); 701 rcu_read_unlock(); 702 703 numa_default_policy(); 704 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES); 705 rcu_read_lock(); 706 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns); 707 rcu_read_unlock(); 708 709 /* 710 * Enable might_sleep() and smp_processor_id() checks. 711 * They cannot be enabled earlier because with CONFIG_PREEMPTION=y 712 * kernel_thread() would trigger might_sleep() splats. With 713 * CONFIG_PREEMPT_VOLUNTARY=y the init task might have scheduled 714 * already, but it's stuck on the kthreadd_done completion. 715 */ 716 system_state = SYSTEM_SCHEDULING; 717 718 complete(&kthreadd_done); 719 720 /* 721 * The boot idle thread must execute schedule() 722 * at least once to get things moving: 723 */ 724 schedule_preempt_disabled(); 725 /* Call into cpu_idle with preempt disabled */ 726 cpu_startup_entry(CPUHP_ONLINE); 727 } 728 729 /* Check for early params. */ 730 static int __init do_early_param(char *param, char *val, 731 const char *unused, void *arg) 732 { 733 const struct obs_kernel_param *p; 734 735 for (p = __setup_start; p < __setup_end; p++) { 736 if ((p->early && parameq(param, p->str)) || 737 (strcmp(param, "console") == 0 && 738 strcmp(p->str, "earlycon") == 0) 739 ) { 740 if (p->setup_func(val) != 0) 741 pr_warn("Malformed early option '%s'\n", param); 742 } 743 } 744 /* We accept everything at this stage. */ 745 return 0; 746 } 747 748 void __init parse_early_options(char *cmdline) 749 { 750 parse_args("early options", cmdline, NULL, 0, 0, 0, NULL, 751 do_early_param); 752 } 753 754 /* Arch code calls this early on, or if not, just before other parsing. */ 755 void __init parse_early_param(void) 756 { 757 static int done __initdata; 758 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; 759 760 if (done) 761 return; 762 763 /* All fall through to do_early_param. */ 764 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); 765 parse_early_options(tmp_cmdline); 766 done = 1; 767 } 768 769 void __init __weak arch_post_acpi_subsys_init(void) { } 770 771 void __init __weak smp_setup_processor_id(void) 772 { 773 } 774 775 # if THREAD_SIZE >= PAGE_SIZE 776 void __init __weak thread_stack_cache_init(void) 777 { 778 } 779 #endif 780 781 void __init __weak mem_encrypt_init(void) { } 782 783 void __init __weak poking_init(void) { } 784 785 void __init __weak pgtable_cache_init(void) { } 786 787 void __init __weak trap_init(void) { } 788 789 bool initcall_debug; 790 core_param(initcall_debug, initcall_debug, bool, 0644); 791 792 #ifdef TRACEPOINTS_ENABLED 793 static void __init initcall_debug_enable(void); 794 #else 795 static inline void initcall_debug_enable(void) 796 { 797 } 798 #endif 799 800 /* Report memory auto-initialization states for this boot. */ 801 static void __init report_meminit(void) 802 { 803 const char *stack; 804 805 if (IS_ENABLED(CONFIG_INIT_STACK_ALL_PATTERN)) 806 stack = "all(pattern)"; 807 else if (IS_ENABLED(CONFIG_INIT_STACK_ALL_ZERO)) 808 stack = "all(zero)"; 809 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL)) 810 stack = "byref_all(zero)"; 811 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF)) 812 stack = "byref(zero)"; 813 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_USER)) 814 stack = "__user(zero)"; 815 else 816 stack = "off"; 817 818 pr_info("mem auto-init: stack:%s, heap alloc:%s, heap free:%s\n", 819 stack, want_init_on_alloc(GFP_KERNEL) ? "on" : "off", 820 want_init_on_free() ? "on" : "off"); 821 if (want_init_on_free()) 822 pr_info("mem auto-init: clearing system memory may take some time...\n"); 823 } 824 825 /* 826 * Set up kernel memory allocators 827 */ 828 static void __init mm_init(void) 829 { 830 /* 831 * page_ext requires contiguous pages, 832 * bigger than MAX_ORDER unless SPARSEMEM. 833 */ 834 page_ext_init_flatmem(); 835 init_mem_debugging_and_hardening(); 836 kfence_alloc_pool(); 837 report_meminit(); 838 stack_depot_early_init(); 839 mem_init(); 840 mem_init_print_info(); 841 kmem_cache_init(); 842 /* 843 * page_owner must be initialized after buddy is ready, and also after 844 * slab is ready so that stack_depot_init() works properly 845 */ 846 page_ext_init_flatmem_late(); 847 kmemleak_init(); 848 pgtable_init(); 849 debug_objects_mem_init(); 850 vmalloc_init(); 851 /* Should be run before the first non-init thread is created */ 852 init_espfix_bsp(); 853 /* Should be run after espfix64 is set up. */ 854 pti_init(); 855 } 856 857 #ifdef CONFIG_RANDOMIZE_KSTACK_OFFSET 858 DEFINE_STATIC_KEY_MAYBE_RO(CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT, 859 randomize_kstack_offset); 860 DEFINE_PER_CPU(u32, kstack_offset); 861 862 static int __init early_randomize_kstack_offset(char *buf) 863 { 864 int ret; 865 bool bool_result; 866 867 ret = kstrtobool(buf, &bool_result); 868 if (ret) 869 return ret; 870 871 if (bool_result) 872 static_branch_enable(&randomize_kstack_offset); 873 else 874 static_branch_disable(&randomize_kstack_offset); 875 return 0; 876 } 877 early_param("randomize_kstack_offset", early_randomize_kstack_offset); 878 #endif 879 880 void __init __weak arch_call_rest_init(void) 881 { 882 rest_init(); 883 } 884 885 static void __init print_unknown_bootoptions(void) 886 { 887 char *unknown_options; 888 char *end; 889 const char *const *p; 890 size_t len; 891 892 if (panic_later || (!argv_init[1] && !envp_init[2])) 893 return; 894 895 /* 896 * Determine how many options we have to print out, plus a space 897 * before each 898 */ 899 len = 1; /* null terminator */ 900 for (p = &argv_init[1]; *p; p++) { 901 len++; 902 len += strlen(*p); 903 } 904 for (p = &envp_init[2]; *p; p++) { 905 len++; 906 len += strlen(*p); 907 } 908 909 unknown_options = memblock_alloc(len, SMP_CACHE_BYTES); 910 if (!unknown_options) { 911 pr_err("%s: Failed to allocate %zu bytes\n", 912 __func__, len); 913 return; 914 } 915 end = unknown_options; 916 917 for (p = &argv_init[1]; *p; p++) 918 end += sprintf(end, " %s", *p); 919 for (p = &envp_init[2]; *p; p++) 920 end += sprintf(end, " %s", *p); 921 922 /* Start at unknown_options[1] to skip the initial space */ 923 pr_notice("Unknown kernel command line parameters \"%s\", will be passed to user space.\n", 924 &unknown_options[1]); 925 memblock_free(unknown_options, len); 926 } 927 928 asmlinkage __visible void __init __no_sanitize_address start_kernel(void) 929 { 930 char *command_line; 931 char *after_dashes; 932 933 set_task_stack_end_magic(&init_task); 934 smp_setup_processor_id(); 935 debug_objects_early_init(); 936 init_vmlinux_build_id(); 937 938 cgroup_init_early(); 939 940 local_irq_disable(); 941 early_boot_irqs_disabled = true; 942 943 /* 944 * Interrupts are still disabled. Do necessary setups, then 945 * enable them. 946 */ 947 boot_cpu_init(); 948 page_address_init(); 949 pr_notice("%s", linux_banner); 950 early_security_init(); 951 setup_arch(&command_line); 952 setup_boot_config(); 953 setup_command_line(command_line); 954 setup_nr_cpu_ids(); 955 setup_per_cpu_areas(); 956 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */ 957 boot_cpu_hotplug_init(); 958 959 build_all_zonelists(NULL); 960 page_alloc_init(); 961 962 pr_notice("Kernel command line: %s\n", saved_command_line); 963 /* parameters may set static keys */ 964 jump_label_init(); 965 parse_early_param(); 966 after_dashes = parse_args("Booting kernel", 967 static_command_line, __start___param, 968 __stop___param - __start___param, 969 -1, -1, NULL, &unknown_bootoption); 970 print_unknown_bootoptions(); 971 if (!IS_ERR_OR_NULL(after_dashes)) 972 parse_args("Setting init args", after_dashes, NULL, 0, -1, -1, 973 NULL, set_init_arg); 974 if (extra_init_args) 975 parse_args("Setting extra init args", extra_init_args, 976 NULL, 0, -1, -1, NULL, set_init_arg); 977 978 /* 979 * These use large bootmem allocations and must precede 980 * kmem_cache_init() 981 */ 982 setup_log_buf(0); 983 vfs_caches_init_early(); 984 sort_main_extable(); 985 trap_init(); 986 mm_init(); 987 988 ftrace_init(); 989 990 /* trace_printk can be enabled here */ 991 early_trace_init(); 992 993 /* 994 * Set up the scheduler prior starting any interrupts (such as the 995 * timer interrupt). Full topology setup happens at smp_init() 996 * time - but meanwhile we still have a functioning scheduler. 997 */ 998 sched_init(); 999 1000 if (WARN(!irqs_disabled(), 1001 "Interrupts were enabled *very* early, fixing it\n")) 1002 local_irq_disable(); 1003 radix_tree_init(); 1004 1005 /* 1006 * Set up housekeeping before setting up workqueues to allow the unbound 1007 * workqueue to take non-housekeeping into account. 1008 */ 1009 housekeeping_init(); 1010 1011 /* 1012 * Allow workqueue creation and work item queueing/cancelling 1013 * early. Work item execution depends on kthreads and starts after 1014 * workqueue_init(). 1015 */ 1016 workqueue_init_early(); 1017 1018 rcu_init(); 1019 1020 /* Trace events are available after this */ 1021 trace_init(); 1022 1023 if (initcall_debug) 1024 initcall_debug_enable(); 1025 1026 context_tracking_init(); 1027 /* init some links before init_ISA_irqs() */ 1028 early_irq_init(); 1029 init_IRQ(); 1030 tick_init(); 1031 rcu_init_nohz(); 1032 init_timers(); 1033 srcu_init(); 1034 hrtimers_init(); 1035 softirq_init(); 1036 timekeeping_init(); 1037 kfence_init(); 1038 time_init(); 1039 1040 /* 1041 * For best initial stack canary entropy, prepare it after: 1042 * - setup_arch() for any UEFI RNG entropy and boot cmdline access 1043 * - timekeeping_init() for ktime entropy used in random_init() 1044 * - time_init() for making random_get_entropy() work on some platforms 1045 * - random_init() to initialize the RNG from from early entropy sources 1046 */ 1047 random_init(command_line); 1048 boot_init_stack_canary(); 1049 1050 perf_event_init(); 1051 profile_init(); 1052 call_function_init(); 1053 WARN(!irqs_disabled(), "Interrupts were enabled early\n"); 1054 1055 early_boot_irqs_disabled = false; 1056 local_irq_enable(); 1057 1058 kmem_cache_init_late(); 1059 1060 /* 1061 * HACK ALERT! This is early. We're enabling the console before 1062 * we've done PCI setups etc, and console_init() must be aware of 1063 * this. But we do want output early, in case something goes wrong. 1064 */ 1065 console_init(); 1066 if (panic_later) 1067 panic("Too many boot %s vars at `%s'", panic_later, 1068 panic_param); 1069 1070 lockdep_init(); 1071 1072 /* 1073 * Need to run this when irqs are enabled, because it wants 1074 * to self-test [hard/soft]-irqs on/off lock inversion bugs 1075 * too: 1076 */ 1077 locking_selftest(); 1078 1079 /* 1080 * This needs to be called before any devices perform DMA 1081 * operations that might use the SWIOTLB bounce buffers. It will 1082 * mark the bounce buffers as decrypted so that their usage will 1083 * not cause "plain-text" data to be decrypted when accessed. 1084 */ 1085 mem_encrypt_init(); 1086 1087 #ifdef CONFIG_BLK_DEV_INITRD 1088 if (initrd_start && !initrd_below_start_ok && 1089 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) { 1090 pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n", 1091 page_to_pfn(virt_to_page((void *)initrd_start)), 1092 min_low_pfn); 1093 initrd_start = 0; 1094 } 1095 #endif 1096 setup_per_cpu_pageset(); 1097 numa_policy_init(); 1098 acpi_early_init(); 1099 if (late_time_init) 1100 late_time_init(); 1101 sched_clock_init(); 1102 calibrate_delay(); 1103 pid_idr_init(); 1104 anon_vma_init(); 1105 #ifdef CONFIG_X86 1106 if (efi_enabled(EFI_RUNTIME_SERVICES)) 1107 efi_enter_virtual_mode(); 1108 #endif 1109 thread_stack_cache_init(); 1110 cred_init(); 1111 fork_init(); 1112 proc_caches_init(); 1113 uts_ns_init(); 1114 key_init(); 1115 security_init(); 1116 dbg_late_init(); 1117 net_ns_init(); 1118 vfs_caches_init(); 1119 pagecache_init(); 1120 signals_init(); 1121 seq_file_init(); 1122 proc_root_init(); 1123 nsfs_init(); 1124 cpuset_init(); 1125 cgroup_init(); 1126 taskstats_init_early(); 1127 delayacct_init(); 1128 1129 poking_init(); 1130 check_bugs(); 1131 1132 acpi_subsystem_init(); 1133 arch_post_acpi_subsys_init(); 1134 kcsan_init(); 1135 1136 /* Do the rest non-__init'ed, we're now alive */ 1137 arch_call_rest_init(); 1138 1139 prevent_tail_call_optimization(); 1140 } 1141 1142 /* Call all constructor functions linked into the kernel. */ 1143 static void __init do_ctors(void) 1144 { 1145 /* 1146 * For UML, the constructors have already been called by the 1147 * normal setup code as it's just a normal ELF binary, so we 1148 * cannot do it again - but we do need CONFIG_CONSTRUCTORS 1149 * even on UML for modules. 1150 */ 1151 #if defined(CONFIG_CONSTRUCTORS) && !defined(CONFIG_UML) 1152 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start; 1153 1154 for (; fn < (ctor_fn_t *) __ctors_end; fn++) 1155 (*fn)(); 1156 #endif 1157 } 1158 1159 #ifdef CONFIG_KALLSYMS 1160 struct blacklist_entry { 1161 struct list_head next; 1162 char *buf; 1163 }; 1164 1165 static __initdata_or_module LIST_HEAD(blacklisted_initcalls); 1166 1167 static int __init initcall_blacklist(char *str) 1168 { 1169 char *str_entry; 1170 struct blacklist_entry *entry; 1171 1172 /* str argument is a comma-separated list of functions */ 1173 do { 1174 str_entry = strsep(&str, ","); 1175 if (str_entry) { 1176 pr_debug("blacklisting initcall %s\n", str_entry); 1177 entry = memblock_alloc(sizeof(*entry), 1178 SMP_CACHE_BYTES); 1179 if (!entry) 1180 panic("%s: Failed to allocate %zu bytes\n", 1181 __func__, sizeof(*entry)); 1182 entry->buf = memblock_alloc(strlen(str_entry) + 1, 1183 SMP_CACHE_BYTES); 1184 if (!entry->buf) 1185 panic("%s: Failed to allocate %zu bytes\n", 1186 __func__, strlen(str_entry) + 1); 1187 strcpy(entry->buf, str_entry); 1188 list_add(&entry->next, &blacklisted_initcalls); 1189 } 1190 } while (str_entry); 1191 1192 return 1; 1193 } 1194 1195 static bool __init_or_module initcall_blacklisted(initcall_t fn) 1196 { 1197 struct blacklist_entry *entry; 1198 char fn_name[KSYM_SYMBOL_LEN]; 1199 unsigned long addr; 1200 1201 if (list_empty(&blacklisted_initcalls)) 1202 return false; 1203 1204 addr = (unsigned long) dereference_function_descriptor(fn); 1205 sprint_symbol_no_offset(fn_name, addr); 1206 1207 /* 1208 * fn will be "function_name [module_name]" where [module_name] is not 1209 * displayed for built-in init functions. Strip off the [module_name]. 1210 */ 1211 strreplace(fn_name, ' ', '\0'); 1212 1213 list_for_each_entry(entry, &blacklisted_initcalls, next) { 1214 if (!strcmp(fn_name, entry->buf)) { 1215 pr_debug("initcall %s blacklisted\n", fn_name); 1216 return true; 1217 } 1218 } 1219 1220 return false; 1221 } 1222 #else 1223 static int __init initcall_blacklist(char *str) 1224 { 1225 pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n"); 1226 return 0; 1227 } 1228 1229 static bool __init_or_module initcall_blacklisted(initcall_t fn) 1230 { 1231 return false; 1232 } 1233 #endif 1234 __setup("initcall_blacklist=", initcall_blacklist); 1235 1236 static __init_or_module void 1237 trace_initcall_start_cb(void *data, initcall_t fn) 1238 { 1239 ktime_t *calltime = (ktime_t *)data; 1240 1241 printk(KERN_DEBUG "calling %pS @ %i\n", fn, task_pid_nr(current)); 1242 *calltime = ktime_get(); 1243 } 1244 1245 static __init_or_module void 1246 trace_initcall_finish_cb(void *data, initcall_t fn, int ret) 1247 { 1248 ktime_t rettime, *calltime = (ktime_t *)data; 1249 1250 rettime = ktime_get(); 1251 printk(KERN_DEBUG "initcall %pS returned %d after %lld usecs\n", 1252 fn, ret, (unsigned long long)ktime_us_delta(rettime, *calltime)); 1253 } 1254 1255 static ktime_t initcall_calltime; 1256 1257 #ifdef TRACEPOINTS_ENABLED 1258 static void __init initcall_debug_enable(void) 1259 { 1260 int ret; 1261 1262 ret = register_trace_initcall_start(trace_initcall_start_cb, 1263 &initcall_calltime); 1264 ret |= register_trace_initcall_finish(trace_initcall_finish_cb, 1265 &initcall_calltime); 1266 WARN(ret, "Failed to register initcall tracepoints\n"); 1267 } 1268 # define do_trace_initcall_start trace_initcall_start 1269 # define do_trace_initcall_finish trace_initcall_finish 1270 #else 1271 static inline void do_trace_initcall_start(initcall_t fn) 1272 { 1273 if (!initcall_debug) 1274 return; 1275 trace_initcall_start_cb(&initcall_calltime, fn); 1276 } 1277 static inline void do_trace_initcall_finish(initcall_t fn, int ret) 1278 { 1279 if (!initcall_debug) 1280 return; 1281 trace_initcall_finish_cb(&initcall_calltime, fn, ret); 1282 } 1283 #endif /* !TRACEPOINTS_ENABLED */ 1284 1285 int __init_or_module do_one_initcall(initcall_t fn) 1286 { 1287 int count = preempt_count(); 1288 char msgbuf[64]; 1289 int ret; 1290 1291 if (initcall_blacklisted(fn)) 1292 return -EPERM; 1293 1294 do_trace_initcall_start(fn); 1295 ret = fn(); 1296 do_trace_initcall_finish(fn, ret); 1297 1298 msgbuf[0] = 0; 1299 1300 if (preempt_count() != count) { 1301 sprintf(msgbuf, "preemption imbalance "); 1302 preempt_count_set(count); 1303 } 1304 if (irqs_disabled()) { 1305 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf)); 1306 local_irq_enable(); 1307 } 1308 WARN(msgbuf[0], "initcall %pS returned with %s\n", fn, msgbuf); 1309 1310 add_latent_entropy(); 1311 return ret; 1312 } 1313 1314 1315 extern initcall_entry_t __initcall_start[]; 1316 extern initcall_entry_t __initcall0_start[]; 1317 extern initcall_entry_t __initcall1_start[]; 1318 extern initcall_entry_t __initcall2_start[]; 1319 extern initcall_entry_t __initcall3_start[]; 1320 extern initcall_entry_t __initcall4_start[]; 1321 extern initcall_entry_t __initcall5_start[]; 1322 extern initcall_entry_t __initcall6_start[]; 1323 extern initcall_entry_t __initcall7_start[]; 1324 extern initcall_entry_t __initcall_end[]; 1325 1326 static initcall_entry_t *initcall_levels[] __initdata = { 1327 __initcall0_start, 1328 __initcall1_start, 1329 __initcall2_start, 1330 __initcall3_start, 1331 __initcall4_start, 1332 __initcall5_start, 1333 __initcall6_start, 1334 __initcall7_start, 1335 __initcall_end, 1336 }; 1337 1338 /* Keep these in sync with initcalls in include/linux/init.h */ 1339 static const char *initcall_level_names[] __initdata = { 1340 "pure", 1341 "core", 1342 "postcore", 1343 "arch", 1344 "subsys", 1345 "fs", 1346 "device", 1347 "late", 1348 }; 1349 1350 static int __init ignore_unknown_bootoption(char *param, char *val, 1351 const char *unused, void *arg) 1352 { 1353 return 0; 1354 } 1355 1356 static void __init do_initcall_level(int level, char *command_line) 1357 { 1358 initcall_entry_t *fn; 1359 1360 parse_args(initcall_level_names[level], 1361 command_line, __start___param, 1362 __stop___param - __start___param, 1363 level, level, 1364 NULL, ignore_unknown_bootoption); 1365 1366 trace_initcall_level(initcall_level_names[level]); 1367 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++) 1368 do_one_initcall(initcall_from_entry(fn)); 1369 } 1370 1371 static void __init do_initcalls(void) 1372 { 1373 int level; 1374 size_t len = strlen(saved_command_line) + 1; 1375 char *command_line; 1376 1377 command_line = kzalloc(len, GFP_KERNEL); 1378 if (!command_line) 1379 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 1380 1381 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) { 1382 /* Parser modifies command_line, restore it each time */ 1383 strcpy(command_line, saved_command_line); 1384 do_initcall_level(level, command_line); 1385 } 1386 1387 kfree(command_line); 1388 } 1389 1390 /* 1391 * Ok, the machine is now initialized. None of the devices 1392 * have been touched yet, but the CPU subsystem is up and 1393 * running, and memory and process management works. 1394 * 1395 * Now we can finally start doing some real work.. 1396 */ 1397 static void __init do_basic_setup(void) 1398 { 1399 cpuset_init_smp(); 1400 driver_init(); 1401 init_irq_proc(); 1402 do_ctors(); 1403 do_initcalls(); 1404 } 1405 1406 static void __init do_pre_smp_initcalls(void) 1407 { 1408 initcall_entry_t *fn; 1409 1410 trace_initcall_level("early"); 1411 for (fn = __initcall_start; fn < __initcall0_start; fn++) 1412 do_one_initcall(initcall_from_entry(fn)); 1413 } 1414 1415 static int run_init_process(const char *init_filename) 1416 { 1417 const char *const *p; 1418 1419 argv_init[0] = init_filename; 1420 pr_info("Run %s as init process\n", init_filename); 1421 pr_debug(" with arguments:\n"); 1422 for (p = argv_init; *p; p++) 1423 pr_debug(" %s\n", *p); 1424 pr_debug(" with environment:\n"); 1425 for (p = envp_init; *p; p++) 1426 pr_debug(" %s\n", *p); 1427 return kernel_execve(init_filename, argv_init, envp_init); 1428 } 1429 1430 static int try_to_run_init_process(const char *init_filename) 1431 { 1432 int ret; 1433 1434 ret = run_init_process(init_filename); 1435 1436 if (ret && ret != -ENOENT) { 1437 pr_err("Starting init: %s exists but couldn't execute it (error %d)\n", 1438 init_filename, ret); 1439 } 1440 1441 return ret; 1442 } 1443 1444 static noinline void __init kernel_init_freeable(void); 1445 1446 #if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX) 1447 bool rodata_enabled __ro_after_init = true; 1448 static int __init set_debug_rodata(char *str) 1449 { 1450 if (strtobool(str, &rodata_enabled)) 1451 pr_warn("Invalid option string for rodata: '%s'\n", str); 1452 return 1; 1453 } 1454 __setup("rodata=", set_debug_rodata); 1455 #endif 1456 1457 #ifdef CONFIG_STRICT_KERNEL_RWX 1458 static void mark_readonly(void) 1459 { 1460 if (rodata_enabled) { 1461 /* 1462 * load_module() results in W+X mappings, which are cleaned 1463 * up with call_rcu(). Let's make sure that queued work is 1464 * flushed so that we don't hit false positives looking for 1465 * insecure pages which are W+X. 1466 */ 1467 rcu_barrier(); 1468 mark_rodata_ro(); 1469 rodata_test(); 1470 } else 1471 pr_info("Kernel memory protection disabled.\n"); 1472 } 1473 #elif defined(CONFIG_ARCH_HAS_STRICT_KERNEL_RWX) 1474 static inline void mark_readonly(void) 1475 { 1476 pr_warn("Kernel memory protection not selected by kernel config.\n"); 1477 } 1478 #else 1479 static inline void mark_readonly(void) 1480 { 1481 pr_warn("This architecture does not have kernel memory protection.\n"); 1482 } 1483 #endif 1484 1485 void __weak free_initmem(void) 1486 { 1487 free_initmem_default(POISON_FREE_INITMEM); 1488 } 1489 1490 static int __ref kernel_init(void *unused) 1491 { 1492 int ret; 1493 1494 /* 1495 * Wait until kthreadd is all set-up. 1496 */ 1497 wait_for_completion(&kthreadd_done); 1498 1499 kernel_init_freeable(); 1500 /* need to finish all async __init code before freeing the memory */ 1501 async_synchronize_full(); 1502 1503 system_state = SYSTEM_FREEING_INITMEM; 1504 kprobe_free_init_mem(); 1505 ftrace_free_init_mem(); 1506 kgdb_free_init_mem(); 1507 exit_boot_config(); 1508 free_initmem(); 1509 mark_readonly(); 1510 1511 /* 1512 * Kernel mappings are now finalized - update the userspace page-table 1513 * to finalize PTI. 1514 */ 1515 pti_finalize(); 1516 1517 system_state = SYSTEM_RUNNING; 1518 numa_default_policy(); 1519 1520 rcu_end_inkernel_boot(); 1521 1522 do_sysctl_args(); 1523 1524 if (ramdisk_execute_command) { 1525 ret = run_init_process(ramdisk_execute_command); 1526 if (!ret) 1527 return 0; 1528 pr_err("Failed to execute %s (error %d)\n", 1529 ramdisk_execute_command, ret); 1530 } 1531 1532 /* 1533 * We try each of these until one succeeds. 1534 * 1535 * The Bourne shell can be used instead of init if we are 1536 * trying to recover a really broken machine. 1537 */ 1538 if (execute_command) { 1539 ret = run_init_process(execute_command); 1540 if (!ret) 1541 return 0; 1542 panic("Requested init %s failed (error %d).", 1543 execute_command, ret); 1544 } 1545 1546 if (CONFIG_DEFAULT_INIT[0] != '\0') { 1547 ret = run_init_process(CONFIG_DEFAULT_INIT); 1548 if (ret) 1549 pr_err("Default init %s failed (error %d)\n", 1550 CONFIG_DEFAULT_INIT, ret); 1551 else 1552 return 0; 1553 } 1554 1555 if (!try_to_run_init_process("/sbin/init") || 1556 !try_to_run_init_process("/etc/init") || 1557 !try_to_run_init_process("/bin/init") || 1558 !try_to_run_init_process("/bin/sh")) 1559 return 0; 1560 1561 panic("No working init found. Try passing init= option to kernel. " 1562 "See Linux Documentation/admin-guide/init.rst for guidance."); 1563 } 1564 1565 /* Open /dev/console, for stdin/stdout/stderr, this should never fail */ 1566 void __init console_on_rootfs(void) 1567 { 1568 struct file *file = filp_open("/dev/console", O_RDWR, 0); 1569 1570 if (IS_ERR(file)) { 1571 pr_err("Warning: unable to open an initial console.\n"); 1572 return; 1573 } 1574 init_dup(file); 1575 init_dup(file); 1576 init_dup(file); 1577 fput(file); 1578 } 1579 1580 static noinline void __init kernel_init_freeable(void) 1581 { 1582 /* Now the scheduler is fully set up and can do blocking allocations */ 1583 gfp_allowed_mask = __GFP_BITS_MASK; 1584 1585 /* 1586 * init can allocate pages on any node 1587 */ 1588 set_mems_allowed(node_states[N_MEMORY]); 1589 1590 cad_pid = get_pid(task_pid(current)); 1591 1592 smp_prepare_cpus(setup_max_cpus); 1593 1594 workqueue_init(); 1595 1596 init_mm_internals(); 1597 1598 rcu_init_tasks_generic(); 1599 do_pre_smp_initcalls(); 1600 lockup_detector_init(); 1601 1602 smp_init(); 1603 sched_init_smp(); 1604 1605 padata_init(); 1606 page_alloc_init_late(); 1607 /* Initialize page ext after all struct pages are initialized. */ 1608 page_ext_init(); 1609 1610 do_basic_setup(); 1611 1612 kunit_run_all_tests(); 1613 1614 wait_for_initramfs(); 1615 console_on_rootfs(); 1616 1617 /* 1618 * check if there is an early userspace init. If yes, let it do all 1619 * the work 1620 */ 1621 if (init_eaccess(ramdisk_execute_command) != 0) { 1622 ramdisk_execute_command = NULL; 1623 prepare_namespace(); 1624 } 1625 1626 /* 1627 * Ok, we have completed the initial bootup, and 1628 * we're essentially up and running. Get rid of the 1629 * initmem segments and start the user-mode stuff.. 1630 * 1631 * rootfs is available now, try loading the public keys 1632 * and default modules 1633 */ 1634 1635 integrity_load_keys(); 1636 } 1637