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(u32 *_size, u32 *_csum) 270 { 271 u32 size, csum; 272 char *data; 273 u32 *hdr; 274 int i; 275 276 if (!initrd_end) 277 return NULL; 278 279 data = (char *)initrd_end - BOOTCONFIG_MAGIC_LEN; 280 /* 281 * Since Grub may align the size of initrd to 4, we must 282 * check the preceding 3 bytes as well. 283 */ 284 for (i = 0; i < 4; i++) { 285 if (!memcmp(data, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN)) 286 goto found; 287 data--; 288 } 289 return NULL; 290 291 found: 292 hdr = (u32 *)(data - 8); 293 size = le32_to_cpu(hdr[0]); 294 csum = le32_to_cpu(hdr[1]); 295 296 data = ((void *)hdr) - size; 297 if ((unsigned long)data < initrd_start) { 298 pr_err("bootconfig size %d is greater than initrd size %ld\n", 299 size, initrd_end - initrd_start); 300 return NULL; 301 } 302 303 /* Remove bootconfig from initramfs/initrd */ 304 initrd_end = (unsigned long)data; 305 if (_size) 306 *_size = size; 307 if (_csum) 308 *_csum = csum; 309 310 return data; 311 } 312 #else 313 static void * __init get_boot_config_from_initrd(u32 *_size, u32 *_csum) 314 { 315 return NULL; 316 } 317 #endif 318 319 #ifdef CONFIG_BOOT_CONFIG 320 321 static char xbc_namebuf[XBC_KEYLEN_MAX] __initdata; 322 323 #define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0) 324 325 static int __init xbc_snprint_cmdline(char *buf, size_t size, 326 struct xbc_node *root) 327 { 328 struct xbc_node *knode, *vnode; 329 char *end = buf + size; 330 const char *val; 331 int ret; 332 333 xbc_node_for_each_key_value(root, knode, val) { 334 ret = xbc_node_compose_key_after(root, knode, 335 xbc_namebuf, XBC_KEYLEN_MAX); 336 if (ret < 0) 337 return ret; 338 339 vnode = xbc_node_get_child(knode); 340 if (!vnode) { 341 ret = snprintf(buf, rest(buf, end), "%s ", xbc_namebuf); 342 if (ret < 0) 343 return ret; 344 buf += ret; 345 continue; 346 } 347 xbc_array_for_each_value(vnode, val) { 348 ret = snprintf(buf, rest(buf, end), "%s=\"%s\" ", 349 xbc_namebuf, val); 350 if (ret < 0) 351 return ret; 352 buf += ret; 353 } 354 } 355 356 return buf - (end - size); 357 } 358 #undef rest 359 360 /* Make an extra command line under given key word */ 361 static char * __init xbc_make_cmdline(const char *key) 362 { 363 struct xbc_node *root; 364 char *new_cmdline; 365 int ret, len = 0; 366 367 root = xbc_find_node(key); 368 if (!root) 369 return NULL; 370 371 /* Count required buffer size */ 372 len = xbc_snprint_cmdline(NULL, 0, root); 373 if (len <= 0) 374 return NULL; 375 376 new_cmdline = memblock_alloc(len + 1, SMP_CACHE_BYTES); 377 if (!new_cmdline) { 378 pr_err("Failed to allocate memory for extra kernel cmdline.\n"); 379 return NULL; 380 } 381 382 ret = xbc_snprint_cmdline(new_cmdline, len + 1, root); 383 if (ret < 0 || ret > len) { 384 pr_err("Failed to print extra kernel cmdline.\n"); 385 memblock_free(new_cmdline, len + 1); 386 return NULL; 387 } 388 389 return new_cmdline; 390 } 391 392 static int __init bootconfig_params(char *param, char *val, 393 const char *unused, void *arg) 394 { 395 if (strcmp(param, "bootconfig") == 0) { 396 bootconfig_found = true; 397 } 398 return 0; 399 } 400 401 static int __init warn_bootconfig(char *str) 402 { 403 /* The 'bootconfig' has been handled by bootconfig_params(). */ 404 return 0; 405 } 406 407 static void __init setup_boot_config(void) 408 { 409 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; 410 const char *msg; 411 int pos; 412 u32 size, csum; 413 char *data, *err; 414 int ret; 415 416 /* Cut out the bootconfig data even if we have no bootconfig option */ 417 data = get_boot_config_from_initrd(&size, &csum); 418 419 strlcpy(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) 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 pr_err("'bootconfig' found on command line, but no bootconfig found\n"); 432 return; 433 } 434 435 if (size >= XBC_DATA_MAX) { 436 pr_err("bootconfig size %d greater than max size %d\n", 437 size, XBC_DATA_MAX); 438 return; 439 } 440 441 if (xbc_calc_checksum(data, size) != csum) { 442 pr_err("bootconfig checksum failed\n"); 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: %d bytes %d nodes\n", 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, 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 = kernel_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 1039 /* 1040 * For best initial stack canary entropy, prepare it after: 1041 * - setup_arch() for any UEFI RNG entropy and boot cmdline access 1042 * - timekeeping_init() for ktime entropy used in rand_initialize() 1043 * - rand_initialize() to get any arch-specific entropy like RDRAND 1044 * - add_latent_entropy() to get any latent entropy 1045 * - adding command line entropy 1046 */ 1047 rand_initialize(); 1048 add_latent_entropy(); 1049 add_device_randomness(command_line, strlen(command_line)); 1050 boot_init_stack_canary(); 1051 1052 time_init(); 1053 perf_event_init(); 1054 profile_init(); 1055 call_function_init(); 1056 WARN(!irqs_disabled(), "Interrupts were enabled early\n"); 1057 1058 early_boot_irqs_disabled = false; 1059 local_irq_enable(); 1060 1061 kmem_cache_init_late(); 1062 1063 /* 1064 * HACK ALERT! This is early. We're enabling the console before 1065 * we've done PCI setups etc, and console_init() must be aware of 1066 * this. But we do want output early, in case something goes wrong. 1067 */ 1068 console_init(); 1069 if (panic_later) 1070 panic("Too many boot %s vars at `%s'", panic_later, 1071 panic_param); 1072 1073 lockdep_init(); 1074 1075 /* 1076 * Need to run this when irqs are enabled, because it wants 1077 * to self-test [hard/soft]-irqs on/off lock inversion bugs 1078 * too: 1079 */ 1080 locking_selftest(); 1081 1082 /* 1083 * This needs to be called before any devices perform DMA 1084 * operations that might use the SWIOTLB bounce buffers. It will 1085 * mark the bounce buffers as decrypted so that their usage will 1086 * not cause "plain-text" data to be decrypted when accessed. 1087 */ 1088 mem_encrypt_init(); 1089 1090 #ifdef CONFIG_BLK_DEV_INITRD 1091 if (initrd_start && !initrd_below_start_ok && 1092 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) { 1093 pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n", 1094 page_to_pfn(virt_to_page((void *)initrd_start)), 1095 min_low_pfn); 1096 initrd_start = 0; 1097 } 1098 #endif 1099 setup_per_cpu_pageset(); 1100 numa_policy_init(); 1101 acpi_early_init(); 1102 if (late_time_init) 1103 late_time_init(); 1104 sched_clock_init(); 1105 calibrate_delay(); 1106 pid_idr_init(); 1107 anon_vma_init(); 1108 #ifdef CONFIG_X86 1109 if (efi_enabled(EFI_RUNTIME_SERVICES)) 1110 efi_enter_virtual_mode(); 1111 #endif 1112 thread_stack_cache_init(); 1113 cred_init(); 1114 fork_init(); 1115 proc_caches_init(); 1116 uts_ns_init(); 1117 key_init(); 1118 security_init(); 1119 dbg_late_init(); 1120 net_ns_init(); 1121 vfs_caches_init(); 1122 pagecache_init(); 1123 signals_init(); 1124 seq_file_init(); 1125 proc_root_init(); 1126 nsfs_init(); 1127 cpuset_init(); 1128 cgroup_init(); 1129 taskstats_init_early(); 1130 delayacct_init(); 1131 1132 poking_init(); 1133 check_bugs(); 1134 1135 acpi_subsystem_init(); 1136 arch_post_acpi_subsys_init(); 1137 kcsan_init(); 1138 1139 /* Do the rest non-__init'ed, we're now alive */ 1140 arch_call_rest_init(); 1141 1142 prevent_tail_call_optimization(); 1143 } 1144 1145 /* Call all constructor functions linked into the kernel. */ 1146 static void __init do_ctors(void) 1147 { 1148 /* 1149 * For UML, the constructors have already been called by the 1150 * normal setup code as it's just a normal ELF binary, so we 1151 * cannot do it again - but we do need CONFIG_CONSTRUCTORS 1152 * even on UML for modules. 1153 */ 1154 #if defined(CONFIG_CONSTRUCTORS) && !defined(CONFIG_UML) 1155 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start; 1156 1157 for (; fn < (ctor_fn_t *) __ctors_end; fn++) 1158 (*fn)(); 1159 #endif 1160 } 1161 1162 #ifdef CONFIG_KALLSYMS 1163 struct blacklist_entry { 1164 struct list_head next; 1165 char *buf; 1166 }; 1167 1168 static __initdata_or_module LIST_HEAD(blacklisted_initcalls); 1169 1170 static int __init initcall_blacklist(char *str) 1171 { 1172 char *str_entry; 1173 struct blacklist_entry *entry; 1174 1175 /* str argument is a comma-separated list of functions */ 1176 do { 1177 str_entry = strsep(&str, ","); 1178 if (str_entry) { 1179 pr_debug("blacklisting initcall %s\n", str_entry); 1180 entry = memblock_alloc(sizeof(*entry), 1181 SMP_CACHE_BYTES); 1182 if (!entry) 1183 panic("%s: Failed to allocate %zu bytes\n", 1184 __func__, sizeof(*entry)); 1185 entry->buf = memblock_alloc(strlen(str_entry) + 1, 1186 SMP_CACHE_BYTES); 1187 if (!entry->buf) 1188 panic("%s: Failed to allocate %zu bytes\n", 1189 __func__, strlen(str_entry) + 1); 1190 strcpy(entry->buf, str_entry); 1191 list_add(&entry->next, &blacklisted_initcalls); 1192 } 1193 } while (str_entry); 1194 1195 return 1; 1196 } 1197 1198 static bool __init_or_module initcall_blacklisted(initcall_t fn) 1199 { 1200 struct blacklist_entry *entry; 1201 char fn_name[KSYM_SYMBOL_LEN]; 1202 unsigned long addr; 1203 1204 if (list_empty(&blacklisted_initcalls)) 1205 return false; 1206 1207 addr = (unsigned long) dereference_function_descriptor(fn); 1208 sprint_symbol_no_offset(fn_name, addr); 1209 1210 /* 1211 * fn will be "function_name [module_name]" where [module_name] is not 1212 * displayed for built-in init functions. Strip off the [module_name]. 1213 */ 1214 strreplace(fn_name, ' ', '\0'); 1215 1216 list_for_each_entry(entry, &blacklisted_initcalls, next) { 1217 if (!strcmp(fn_name, entry->buf)) { 1218 pr_debug("initcall %s blacklisted\n", fn_name); 1219 return true; 1220 } 1221 } 1222 1223 return false; 1224 } 1225 #else 1226 static int __init initcall_blacklist(char *str) 1227 { 1228 pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n"); 1229 return 0; 1230 } 1231 1232 static bool __init_or_module initcall_blacklisted(initcall_t fn) 1233 { 1234 return false; 1235 } 1236 #endif 1237 __setup("initcall_blacklist=", initcall_blacklist); 1238 1239 static __init_or_module void 1240 trace_initcall_start_cb(void *data, initcall_t fn) 1241 { 1242 ktime_t *calltime = (ktime_t *)data; 1243 1244 printk(KERN_DEBUG "calling %pS @ %i\n", fn, task_pid_nr(current)); 1245 *calltime = ktime_get(); 1246 } 1247 1248 static __init_or_module void 1249 trace_initcall_finish_cb(void *data, initcall_t fn, int ret) 1250 { 1251 ktime_t rettime, *calltime = (ktime_t *)data; 1252 1253 rettime = ktime_get(); 1254 printk(KERN_DEBUG "initcall %pS returned %d after %lld usecs\n", 1255 fn, ret, (unsigned long long)ktime_us_delta(rettime, *calltime)); 1256 } 1257 1258 static ktime_t initcall_calltime; 1259 1260 #ifdef TRACEPOINTS_ENABLED 1261 static void __init initcall_debug_enable(void) 1262 { 1263 int ret; 1264 1265 ret = register_trace_initcall_start(trace_initcall_start_cb, 1266 &initcall_calltime); 1267 ret |= register_trace_initcall_finish(trace_initcall_finish_cb, 1268 &initcall_calltime); 1269 WARN(ret, "Failed to register initcall tracepoints\n"); 1270 } 1271 # define do_trace_initcall_start trace_initcall_start 1272 # define do_trace_initcall_finish trace_initcall_finish 1273 #else 1274 static inline void do_trace_initcall_start(initcall_t fn) 1275 { 1276 if (!initcall_debug) 1277 return; 1278 trace_initcall_start_cb(&initcall_calltime, fn); 1279 } 1280 static inline void do_trace_initcall_finish(initcall_t fn, int ret) 1281 { 1282 if (!initcall_debug) 1283 return; 1284 trace_initcall_finish_cb(&initcall_calltime, fn, ret); 1285 } 1286 #endif /* !TRACEPOINTS_ENABLED */ 1287 1288 int __init_or_module do_one_initcall(initcall_t fn) 1289 { 1290 int count = preempt_count(); 1291 char msgbuf[64]; 1292 int ret; 1293 1294 if (initcall_blacklisted(fn)) 1295 return -EPERM; 1296 1297 do_trace_initcall_start(fn); 1298 ret = fn(); 1299 do_trace_initcall_finish(fn, ret); 1300 1301 msgbuf[0] = 0; 1302 1303 if (preempt_count() != count) { 1304 sprintf(msgbuf, "preemption imbalance "); 1305 preempt_count_set(count); 1306 } 1307 if (irqs_disabled()) { 1308 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf)); 1309 local_irq_enable(); 1310 } 1311 WARN(msgbuf[0], "initcall %pS returned with %s\n", fn, msgbuf); 1312 1313 add_latent_entropy(); 1314 return ret; 1315 } 1316 1317 1318 extern initcall_entry_t __initcall_start[]; 1319 extern initcall_entry_t __initcall0_start[]; 1320 extern initcall_entry_t __initcall1_start[]; 1321 extern initcall_entry_t __initcall2_start[]; 1322 extern initcall_entry_t __initcall3_start[]; 1323 extern initcall_entry_t __initcall4_start[]; 1324 extern initcall_entry_t __initcall5_start[]; 1325 extern initcall_entry_t __initcall6_start[]; 1326 extern initcall_entry_t __initcall7_start[]; 1327 extern initcall_entry_t __initcall_end[]; 1328 1329 static initcall_entry_t *initcall_levels[] __initdata = { 1330 __initcall0_start, 1331 __initcall1_start, 1332 __initcall2_start, 1333 __initcall3_start, 1334 __initcall4_start, 1335 __initcall5_start, 1336 __initcall6_start, 1337 __initcall7_start, 1338 __initcall_end, 1339 }; 1340 1341 /* Keep these in sync with initcalls in include/linux/init.h */ 1342 static const char *initcall_level_names[] __initdata = { 1343 "pure", 1344 "core", 1345 "postcore", 1346 "arch", 1347 "subsys", 1348 "fs", 1349 "device", 1350 "late", 1351 }; 1352 1353 static int __init ignore_unknown_bootoption(char *param, char *val, 1354 const char *unused, void *arg) 1355 { 1356 return 0; 1357 } 1358 1359 static void __init do_initcall_level(int level, char *command_line) 1360 { 1361 initcall_entry_t *fn; 1362 1363 parse_args(initcall_level_names[level], 1364 command_line, __start___param, 1365 __stop___param - __start___param, 1366 level, level, 1367 NULL, ignore_unknown_bootoption); 1368 1369 trace_initcall_level(initcall_level_names[level]); 1370 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++) 1371 do_one_initcall(initcall_from_entry(fn)); 1372 } 1373 1374 static void __init do_initcalls(void) 1375 { 1376 int level; 1377 size_t len = strlen(saved_command_line) + 1; 1378 char *command_line; 1379 1380 command_line = kzalloc(len, GFP_KERNEL); 1381 if (!command_line) 1382 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 1383 1384 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) { 1385 /* Parser modifies command_line, restore it each time */ 1386 strcpy(command_line, saved_command_line); 1387 do_initcall_level(level, command_line); 1388 } 1389 1390 kfree(command_line); 1391 } 1392 1393 /* 1394 * Ok, the machine is now initialized. None of the devices 1395 * have been touched yet, but the CPU subsystem is up and 1396 * running, and memory and process management works. 1397 * 1398 * Now we can finally start doing some real work.. 1399 */ 1400 static void __init do_basic_setup(void) 1401 { 1402 cpuset_init_smp(); 1403 driver_init(); 1404 init_irq_proc(); 1405 do_ctors(); 1406 do_initcalls(); 1407 } 1408 1409 static void __init do_pre_smp_initcalls(void) 1410 { 1411 initcall_entry_t *fn; 1412 1413 trace_initcall_level("early"); 1414 for (fn = __initcall_start; fn < __initcall0_start; fn++) 1415 do_one_initcall(initcall_from_entry(fn)); 1416 } 1417 1418 static int run_init_process(const char *init_filename) 1419 { 1420 const char *const *p; 1421 1422 argv_init[0] = init_filename; 1423 pr_info("Run %s as init process\n", init_filename); 1424 pr_debug(" with arguments:\n"); 1425 for (p = argv_init; *p; p++) 1426 pr_debug(" %s\n", *p); 1427 pr_debug(" with environment:\n"); 1428 for (p = envp_init; *p; p++) 1429 pr_debug(" %s\n", *p); 1430 return kernel_execve(init_filename, argv_init, envp_init); 1431 } 1432 1433 static int try_to_run_init_process(const char *init_filename) 1434 { 1435 int ret; 1436 1437 ret = run_init_process(init_filename); 1438 1439 if (ret && ret != -ENOENT) { 1440 pr_err("Starting init: %s exists but couldn't execute it (error %d)\n", 1441 init_filename, ret); 1442 } 1443 1444 return ret; 1445 } 1446 1447 static noinline void __init kernel_init_freeable(void); 1448 1449 #if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX) 1450 bool rodata_enabled __ro_after_init = true; 1451 static int __init set_debug_rodata(char *str) 1452 { 1453 if (strtobool(str, &rodata_enabled)) 1454 pr_warn("Invalid option string for rodata: '%s'\n", str); 1455 return 1; 1456 } 1457 __setup("rodata=", set_debug_rodata); 1458 #endif 1459 1460 #ifdef CONFIG_STRICT_KERNEL_RWX 1461 static void mark_readonly(void) 1462 { 1463 if (rodata_enabled) { 1464 /* 1465 * load_module() results in W+X mappings, which are cleaned 1466 * up with call_rcu(). Let's make sure that queued work is 1467 * flushed so that we don't hit false positives looking for 1468 * insecure pages which are W+X. 1469 */ 1470 rcu_barrier(); 1471 mark_rodata_ro(); 1472 rodata_test(); 1473 } else 1474 pr_info("Kernel memory protection disabled.\n"); 1475 } 1476 #elif defined(CONFIG_ARCH_HAS_STRICT_KERNEL_RWX) 1477 static inline void mark_readonly(void) 1478 { 1479 pr_warn("Kernel memory protection not selected by kernel config.\n"); 1480 } 1481 #else 1482 static inline void mark_readonly(void) 1483 { 1484 pr_warn("This architecture does not have kernel memory protection.\n"); 1485 } 1486 #endif 1487 1488 void __weak free_initmem(void) 1489 { 1490 free_initmem_default(POISON_FREE_INITMEM); 1491 } 1492 1493 static int __ref kernel_init(void *unused) 1494 { 1495 int ret; 1496 1497 /* 1498 * Wait until kthreadd is all set-up. 1499 */ 1500 wait_for_completion(&kthreadd_done); 1501 1502 kernel_init_freeable(); 1503 /* need to finish all async __init code before freeing the memory */ 1504 async_synchronize_full(); 1505 1506 system_state = SYSTEM_FREEING_INITMEM; 1507 kprobe_free_init_mem(); 1508 ftrace_free_init_mem(); 1509 kgdb_free_init_mem(); 1510 exit_boot_config(); 1511 free_initmem(); 1512 mark_readonly(); 1513 1514 /* 1515 * Kernel mappings are now finalized - update the userspace page-table 1516 * to finalize PTI. 1517 */ 1518 pti_finalize(); 1519 1520 system_state = SYSTEM_RUNNING; 1521 numa_default_policy(); 1522 1523 rcu_end_inkernel_boot(); 1524 1525 do_sysctl_args(); 1526 1527 if (ramdisk_execute_command) { 1528 ret = run_init_process(ramdisk_execute_command); 1529 if (!ret) 1530 return 0; 1531 pr_err("Failed to execute %s (error %d)\n", 1532 ramdisk_execute_command, ret); 1533 } 1534 1535 /* 1536 * We try each of these until one succeeds. 1537 * 1538 * The Bourne shell can be used instead of init if we are 1539 * trying to recover a really broken machine. 1540 */ 1541 if (execute_command) { 1542 ret = run_init_process(execute_command); 1543 if (!ret) 1544 return 0; 1545 panic("Requested init %s failed (error %d).", 1546 execute_command, ret); 1547 } 1548 1549 if (CONFIG_DEFAULT_INIT[0] != '\0') { 1550 ret = run_init_process(CONFIG_DEFAULT_INIT); 1551 if (ret) 1552 pr_err("Default init %s failed (error %d)\n", 1553 CONFIG_DEFAULT_INIT, ret); 1554 else 1555 return 0; 1556 } 1557 1558 if (!try_to_run_init_process("/sbin/init") || 1559 !try_to_run_init_process("/etc/init") || 1560 !try_to_run_init_process("/bin/init") || 1561 !try_to_run_init_process("/bin/sh")) 1562 return 0; 1563 1564 panic("No working init found. Try passing init= option to kernel. " 1565 "See Linux Documentation/admin-guide/init.rst for guidance."); 1566 } 1567 1568 /* Open /dev/console, for stdin/stdout/stderr, this should never fail */ 1569 void __init console_on_rootfs(void) 1570 { 1571 struct file *file = filp_open("/dev/console", O_RDWR, 0); 1572 1573 if (IS_ERR(file)) { 1574 pr_err("Warning: unable to open an initial console.\n"); 1575 return; 1576 } 1577 init_dup(file); 1578 init_dup(file); 1579 init_dup(file); 1580 fput(file); 1581 } 1582 1583 static noinline void __init kernel_init_freeable(void) 1584 { 1585 /* Now the scheduler is fully set up and can do blocking allocations */ 1586 gfp_allowed_mask = __GFP_BITS_MASK; 1587 1588 /* 1589 * init can allocate pages on any node 1590 */ 1591 set_mems_allowed(node_states[N_MEMORY]); 1592 1593 cad_pid = get_pid(task_pid(current)); 1594 1595 smp_prepare_cpus(setup_max_cpus); 1596 1597 workqueue_init(); 1598 1599 init_mm_internals(); 1600 1601 rcu_init_tasks_generic(); 1602 do_pre_smp_initcalls(); 1603 lockup_detector_init(); 1604 1605 smp_init(); 1606 sched_init_smp(); 1607 1608 padata_init(); 1609 page_alloc_init_late(); 1610 /* Initialize page ext after all struct pages are initialized. */ 1611 page_ext_init(); 1612 1613 do_basic_setup(); 1614 1615 kunit_run_all_tests(); 1616 1617 wait_for_initramfs(); 1618 console_on_rootfs(); 1619 1620 /* 1621 * check if there is an early userspace init. If yes, let it do all 1622 * the work 1623 */ 1624 if (init_eaccess(ramdisk_execute_command) != 0) { 1625 ramdisk_execute_command = NULL; 1626 prepare_namespace(); 1627 } 1628 1629 /* 1630 * Ok, we have completed the initial bootup, and 1631 * we're essentially up and running. Get rid of the 1632 * initmem segments and start the user-mode stuff.. 1633 * 1634 * rootfs is available now, try loading the public keys 1635 * and default modules 1636 */ 1637 1638 integrity_load_keys(); 1639 } 1640