1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/init/main.c 4 * 5 * Copyright (C) 1991, 1992 Linus Torvalds 6 * 7 * GK 2/5/95 - Changed to support mounting root fs via NFS 8 * Added initrd & change_root: Werner Almesberger & Hans Lermen, Feb '96 9 * Moan early if gcc is old, avoiding bogus kernels - Paul Gortmaker, May '96 10 * Simplified starting of init: Michael A. Griffith <grif@acm.org> 11 */ 12 13 #define DEBUG /* Enable initcall_debug */ 14 15 #include <linux/types.h> 16 #include <linux/extable.h> 17 #include <linux/module.h> 18 #include <linux/proc_fs.h> 19 #include <linux/binfmts.h> 20 #include <linux/kernel.h> 21 #include <linux/syscalls.h> 22 #include <linux/stackprotector.h> 23 #include <linux/string.h> 24 #include <linux/ctype.h> 25 #include <linux/delay.h> 26 #include <linux/ioport.h> 27 #include <linux/init.h> 28 #include <linux/initrd.h> 29 #include <linux/memblock.h> 30 #include <linux/acpi.h> 31 #include <linux/bootconfig.h> 32 #include <linux/console.h> 33 #include <linux/nmi.h> 34 #include <linux/percpu.h> 35 #include <linux/kmod.h> 36 #include <linux/kprobes.h> 37 #include <linux/kmsan.h> 38 #include <linux/vmalloc.h> 39 #include <linux/kernel_stat.h> 40 #include <linux/start_kernel.h> 41 #include <linux/security.h> 42 #include <linux/smp.h> 43 #include <linux/profile.h> 44 #include <linux/kfence.h> 45 #include <linux/rcupdate.h> 46 #include <linux/srcu.h> 47 #include <linux/moduleparam.h> 48 #include <linux/kallsyms.h> 49 #include <linux/buildid.h> 50 #include <linux/writeback.h> 51 #include <linux/cpu.h> 52 #include <linux/cpuset.h> 53 #include <linux/cgroup.h> 54 #include <linux/efi.h> 55 #include <linux/tick.h> 56 #include <linux/sched/isolation.h> 57 #include <linux/interrupt.h> 58 #include <linux/taskstats_kern.h> 59 #include <linux/delayacct.h> 60 #include <linux/unistd.h> 61 #include <linux/utsname.h> 62 #include <linux/rmap.h> 63 #include <linux/mempolicy.h> 64 #include <linux/key.h> 65 #include <linux/page_ext.h> 66 #include <linux/debug_locks.h> 67 #include <linux/debugobjects.h> 68 #include <linux/lockdep.h> 69 #include <linux/kmemleak.h> 70 #include <linux/padata.h> 71 #include <linux/pid_namespace.h> 72 #include <linux/device/driver.h> 73 #include <linux/kthread.h> 74 #include <linux/sched.h> 75 #include <linux/sched/init.h> 76 #include <linux/signal.h> 77 #include <linux/idr.h> 78 #include <linux/kgdb.h> 79 #include <linux/ftrace.h> 80 #include <linux/async.h> 81 #include <linux/shmem_fs.h> 82 #include <linux/slab.h> 83 #include <linux/perf_event.h> 84 #include <linux/ptrace.h> 85 #include <linux/pti.h> 86 #include <linux/blkdev.h> 87 #include <linux/sched/clock.h> 88 #include <linux/sched/task.h> 89 #include <linux/sched/task_stack.h> 90 #include <linux/context_tracking.h> 91 #include <linux/random.h> 92 #include <linux/list.h> 93 #include <linux/integrity.h> 94 #include <linux/proc_ns.h> 95 #include <linux/io.h> 96 #include <linux/cache.h> 97 #include <linux/rodata_test.h> 98 #include <linux/jump_label.h> 99 #include <linux/mem_encrypt.h> 100 #include <linux/kcsan.h> 101 #include <linux/init_syscalls.h> 102 #include <linux/stackdepot.h> 103 #include <linux/randomize_kstack.h> 104 #include <net/net_namespace.h> 105 106 #include <asm/io.h> 107 #include <asm/bugs.h> 108 #include <asm/setup.h> 109 #include <asm/sections.h> 110 #include <asm/cacheflush.h> 111 112 #define CREATE_TRACE_POINTS 113 #include <trace/events/initcall.h> 114 115 #include <kunit/test.h> 116 117 static int kernel_init(void *); 118 119 extern void init_IRQ(void); 120 extern void radix_tree_init(void); 121 extern void maple_tree_init(void); 122 123 /* 124 * Debug helper: via this flag we know that we are in 'early bootup code' 125 * where only the boot processor is running with IRQ disabled. This means 126 * two things - IRQ must not be enabled before the flag is cleared and some 127 * operations which are not allowed with IRQ disabled are allowed while the 128 * flag is set. 129 */ 130 bool early_boot_irqs_disabled __read_mostly; 131 132 enum system_states system_state __read_mostly; 133 EXPORT_SYMBOL(system_state); 134 135 /* 136 * Boot command-line arguments 137 */ 138 #define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT 139 #define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT 140 141 extern void time_init(void); 142 /* Default late time init is NULL. archs can override this later. */ 143 void (*__initdata late_time_init)(void); 144 145 /* Untouched command line saved by arch-specific code. */ 146 char __initdata boot_command_line[COMMAND_LINE_SIZE]; 147 /* Untouched saved command line (eg. for /proc) */ 148 char *saved_command_line __ro_after_init; 149 unsigned int saved_command_line_len __ro_after_init; 150 /* Command line for parameter parsing */ 151 static char *static_command_line; 152 /* Untouched extra command line */ 153 static char *extra_command_line; 154 /* Extra init arguments */ 155 static char *extra_init_args; 156 157 #ifdef CONFIG_BOOT_CONFIG 158 /* Is bootconfig on command line? */ 159 static bool bootconfig_found; 160 static size_t initargs_offs; 161 #else 162 # define bootconfig_found false 163 # define initargs_offs 0 164 #endif 165 166 static char *execute_command; 167 static char *ramdisk_execute_command = "/init"; 168 169 /* 170 * Used to generate warnings if static_key manipulation functions are used 171 * before jump_label_init is called. 172 */ 173 bool static_key_initialized __read_mostly; 174 EXPORT_SYMBOL_GPL(static_key_initialized); 175 176 /* 177 * If set, this is an indication to the drivers that reset the underlying 178 * device before going ahead with the initialization otherwise driver might 179 * rely on the BIOS and skip the reset operation. 180 * 181 * This is useful if kernel is booting in an unreliable environment. 182 * For ex. kdump situation where previous kernel has crashed, BIOS has been 183 * skipped and devices will be in unknown state. 184 */ 185 unsigned int reset_devices; 186 EXPORT_SYMBOL(reset_devices); 187 188 static int __init set_reset_devices(char *str) 189 { 190 reset_devices = 1; 191 return 1; 192 } 193 194 __setup("reset_devices", set_reset_devices); 195 196 static const char *argv_init[MAX_INIT_ARGS+2] = { "init", NULL, }; 197 const char *envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, }; 198 static const char *panic_later, *panic_param; 199 200 extern const struct obs_kernel_param __setup_start[], __setup_end[]; 201 202 static bool __init obsolete_checksetup(char *line) 203 { 204 const struct obs_kernel_param *p; 205 bool had_early_param = false; 206 207 p = __setup_start; 208 do { 209 int n = strlen(p->str); 210 if (parameqn(line, p->str, n)) { 211 if (p->early) { 212 /* Already done in parse_early_param? 213 * (Needs exact match on param part). 214 * Keep iterating, as we can have early 215 * params and __setups of same names 8( */ 216 if (line[n] == '\0' || line[n] == '=') 217 had_early_param = true; 218 } else if (!p->setup_func) { 219 pr_warn("Parameter %s is obsolete, ignored\n", 220 p->str); 221 return true; 222 } else if (p->setup_func(line + n)) 223 return true; 224 } 225 p++; 226 } while (p < __setup_end); 227 228 return had_early_param; 229 } 230 231 /* 232 * This should be approx 2 Bo*oMips to start (note initial shift), and will 233 * still work even if initially too large, it will just take slightly longer 234 */ 235 unsigned long loops_per_jiffy = (1<<12); 236 EXPORT_SYMBOL(loops_per_jiffy); 237 238 static int __init debug_kernel(char *str) 239 { 240 console_loglevel = CONSOLE_LOGLEVEL_DEBUG; 241 return 0; 242 } 243 244 static int __init quiet_kernel(char *str) 245 { 246 console_loglevel = CONSOLE_LOGLEVEL_QUIET; 247 return 0; 248 } 249 250 early_param("debug", debug_kernel); 251 early_param("quiet", quiet_kernel); 252 253 static int __init loglevel(char *str) 254 { 255 int newlevel; 256 257 /* 258 * Only update loglevel value when a correct setting was passed, 259 * to prevent blind crashes (when loglevel being set to 0) that 260 * are quite hard to debug 261 */ 262 if (get_option(&str, &newlevel)) { 263 console_loglevel = newlevel; 264 return 0; 265 } 266 267 return -EINVAL; 268 } 269 270 early_param("loglevel", loglevel); 271 272 #ifdef CONFIG_BLK_DEV_INITRD 273 static void * __init get_boot_config_from_initrd(size_t *_size) 274 { 275 u32 size, csum; 276 char *data; 277 u32 *hdr; 278 int i; 279 280 if (!initrd_end) 281 return NULL; 282 283 data = (char *)initrd_end - BOOTCONFIG_MAGIC_LEN; 284 /* 285 * Since Grub may align the size of initrd to 4, we must 286 * check the preceding 3 bytes as well. 287 */ 288 for (i = 0; i < 4; i++) { 289 if (!memcmp(data, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN)) 290 goto found; 291 data--; 292 } 293 return NULL; 294 295 found: 296 hdr = (u32 *)(data - 8); 297 size = le32_to_cpu(hdr[0]); 298 csum = le32_to_cpu(hdr[1]); 299 300 data = ((void *)hdr) - size; 301 if ((unsigned long)data < initrd_start) { 302 pr_err("bootconfig size %d is greater than initrd size %ld\n", 303 size, initrd_end - initrd_start); 304 return NULL; 305 } 306 307 if (xbc_calc_checksum(data, size) != csum) { 308 pr_err("bootconfig checksum failed\n"); 309 return NULL; 310 } 311 312 /* Remove bootconfig from initramfs/initrd */ 313 initrd_end = (unsigned long)data; 314 if (_size) 315 *_size = size; 316 317 return data; 318 } 319 #else 320 static void * __init get_boot_config_from_initrd(size_t *_size) 321 { 322 return NULL; 323 } 324 #endif 325 326 #ifdef CONFIG_BOOT_CONFIG 327 328 static char xbc_namebuf[XBC_KEYLEN_MAX] __initdata; 329 330 #define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0) 331 332 static int __init xbc_snprint_cmdline(char *buf, size_t size, 333 struct xbc_node *root) 334 { 335 struct xbc_node *knode, *vnode; 336 char *end = buf + size; 337 const char *val; 338 int ret; 339 340 xbc_node_for_each_key_value(root, knode, val) { 341 ret = xbc_node_compose_key_after(root, knode, 342 xbc_namebuf, XBC_KEYLEN_MAX); 343 if (ret < 0) 344 return ret; 345 346 vnode = xbc_node_get_child(knode); 347 if (!vnode) { 348 ret = snprintf(buf, rest(buf, end), "%s ", xbc_namebuf); 349 if (ret < 0) 350 return ret; 351 buf += ret; 352 continue; 353 } 354 xbc_array_for_each_value(vnode, val) { 355 ret = snprintf(buf, rest(buf, end), "%s=\"%s\" ", 356 xbc_namebuf, val); 357 if (ret < 0) 358 return ret; 359 buf += ret; 360 } 361 } 362 363 return buf - (end - size); 364 } 365 #undef rest 366 367 /* Make an extra command line under given key word */ 368 static char * __init xbc_make_cmdline(const char *key) 369 { 370 struct xbc_node *root; 371 char *new_cmdline; 372 int ret, len = 0; 373 374 root = xbc_find_node(key); 375 if (!root) 376 return NULL; 377 378 /* Count required buffer size */ 379 len = xbc_snprint_cmdline(NULL, 0, root); 380 if (len <= 0) 381 return NULL; 382 383 new_cmdline = memblock_alloc(len + 1, SMP_CACHE_BYTES); 384 if (!new_cmdline) { 385 pr_err("Failed to allocate memory for extra kernel cmdline.\n"); 386 return NULL; 387 } 388 389 ret = xbc_snprint_cmdline(new_cmdline, len + 1, root); 390 if (ret < 0 || ret > len) { 391 pr_err("Failed to print extra kernel cmdline.\n"); 392 memblock_free(new_cmdline, len + 1); 393 return NULL; 394 } 395 396 return new_cmdline; 397 } 398 399 static int __init bootconfig_params(char *param, char *val, 400 const char *unused, void *arg) 401 { 402 if (strcmp(param, "bootconfig") == 0) { 403 bootconfig_found = true; 404 } 405 return 0; 406 } 407 408 static int __init warn_bootconfig(char *str) 409 { 410 /* The 'bootconfig' has been handled by bootconfig_params(). */ 411 return 0; 412 } 413 414 static void __init setup_boot_config(void) 415 { 416 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; 417 const char *msg, *data; 418 int pos, ret; 419 size_t size; 420 char *err; 421 422 /* Cut out the bootconfig data even if we have no bootconfig option */ 423 data = get_boot_config_from_initrd(&size); 424 /* If there is no bootconfig in initrd, try embedded one. */ 425 if (!data) 426 data = xbc_get_embedded_bootconfig(&size); 427 428 strscpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); 429 err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL, 430 bootconfig_params); 431 432 if (IS_ERR(err) || !bootconfig_found) 433 return; 434 435 /* parse_args() stops at the next param of '--' and returns an address */ 436 if (err) 437 initargs_offs = err - tmp_cmdline; 438 439 if (!data) { 440 pr_err("'bootconfig' found on command line, but no bootconfig found\n"); 441 return; 442 } 443 444 if (size >= XBC_DATA_MAX) { 445 pr_err("bootconfig size %ld greater than max size %d\n", 446 (long)size, XBC_DATA_MAX); 447 return; 448 } 449 450 ret = xbc_init(data, size, &msg, &pos); 451 if (ret < 0) { 452 if (pos < 0) 453 pr_err("Failed to init bootconfig: %s.\n", msg); 454 else 455 pr_err("Failed to parse bootconfig: %s at %d.\n", 456 msg, pos); 457 } else { 458 xbc_get_info(&ret, NULL); 459 pr_info("Load bootconfig: %ld bytes %d nodes\n", (long)size, ret); 460 /* keys starting with "kernel." are passed via cmdline */ 461 extra_command_line = xbc_make_cmdline("kernel"); 462 /* Also, "init." keys are init arguments */ 463 extra_init_args = xbc_make_cmdline("init"); 464 } 465 return; 466 } 467 468 static void __init exit_boot_config(void) 469 { 470 xbc_exit(); 471 } 472 473 #else /* !CONFIG_BOOT_CONFIG */ 474 475 static void __init setup_boot_config(void) 476 { 477 /* Remove bootconfig data from initrd */ 478 get_boot_config_from_initrd(NULL); 479 } 480 481 static int __init warn_bootconfig(char *str) 482 { 483 pr_warn("WARNING: 'bootconfig' found on the kernel command line but CONFIG_BOOT_CONFIG is not set.\n"); 484 return 0; 485 } 486 487 #define exit_boot_config() do {} while (0) 488 489 #endif /* CONFIG_BOOT_CONFIG */ 490 491 early_param("bootconfig", warn_bootconfig); 492 493 /* Change NUL term back to "=", to make "param" the whole string. */ 494 static void __init repair_env_string(char *param, char *val) 495 { 496 if (val) { 497 /* param=val or param="val"? */ 498 if (val == param+strlen(param)+1) 499 val[-1] = '='; 500 else if (val == param+strlen(param)+2) { 501 val[-2] = '='; 502 memmove(val-1, val, strlen(val)+1); 503 } else 504 BUG(); 505 } 506 } 507 508 /* Anything after -- gets handed straight to init. */ 509 static int __init set_init_arg(char *param, char *val, 510 const char *unused, void *arg) 511 { 512 unsigned int i; 513 514 if (panic_later) 515 return 0; 516 517 repair_env_string(param, val); 518 519 for (i = 0; argv_init[i]; i++) { 520 if (i == MAX_INIT_ARGS) { 521 panic_later = "init"; 522 panic_param = param; 523 return 0; 524 } 525 } 526 argv_init[i] = param; 527 return 0; 528 } 529 530 /* 531 * Unknown boot options get handed to init, unless they look like 532 * unused parameters (modprobe will find them in /proc/cmdline). 533 */ 534 static int __init unknown_bootoption(char *param, char *val, 535 const char *unused, void *arg) 536 { 537 size_t len = strlen(param); 538 539 repair_env_string(param, val); 540 541 /* Handle obsolete-style parameters */ 542 if (obsolete_checksetup(param)) 543 return 0; 544 545 /* Unused module parameter. */ 546 if (strnchr(param, len, '.')) 547 return 0; 548 549 if (panic_later) 550 return 0; 551 552 if (val) { 553 /* Environment option */ 554 unsigned int i; 555 for (i = 0; envp_init[i]; i++) { 556 if (i == MAX_INIT_ENVS) { 557 panic_later = "env"; 558 panic_param = param; 559 } 560 if (!strncmp(param, envp_init[i], len+1)) 561 break; 562 } 563 envp_init[i] = param; 564 } else { 565 /* Command line option */ 566 unsigned int i; 567 for (i = 0; argv_init[i]; i++) { 568 if (i == MAX_INIT_ARGS) { 569 panic_later = "init"; 570 panic_param = param; 571 } 572 } 573 argv_init[i] = param; 574 } 575 return 0; 576 } 577 578 static int __init init_setup(char *str) 579 { 580 unsigned int i; 581 582 execute_command = str; 583 /* 584 * In case LILO is going to boot us with default command line, 585 * it prepends "auto" before the whole cmdline which makes 586 * the shell think it should execute a script with such name. 587 * So we ignore all arguments entered _before_ init=... [MJ] 588 */ 589 for (i = 1; i < MAX_INIT_ARGS; i++) 590 argv_init[i] = NULL; 591 return 1; 592 } 593 __setup("init=", init_setup); 594 595 static int __init rdinit_setup(char *str) 596 { 597 unsigned int i; 598 599 ramdisk_execute_command = str; 600 /* See "auto" comment in init_setup */ 601 for (i = 1; i < MAX_INIT_ARGS; i++) 602 argv_init[i] = NULL; 603 return 1; 604 } 605 __setup("rdinit=", rdinit_setup); 606 607 #ifndef CONFIG_SMP 608 static const unsigned int setup_max_cpus = NR_CPUS; 609 static inline void setup_nr_cpu_ids(void) { } 610 static inline void smp_prepare_cpus(unsigned int maxcpus) { } 611 #endif 612 613 /* 614 * We need to store the untouched command line for future reference. 615 * We also need to store the touched command line since the parameter 616 * parsing is performed in place, and we should allow a component to 617 * store reference of name/value for future reference. 618 */ 619 static void __init setup_command_line(char *command_line) 620 { 621 size_t len, xlen = 0, ilen = 0; 622 623 if (extra_command_line) 624 xlen = strlen(extra_command_line); 625 if (extra_init_args) 626 ilen = strlen(extra_init_args) + 4; /* for " -- " */ 627 628 len = xlen + strlen(boot_command_line) + 1; 629 630 saved_command_line = memblock_alloc(len + ilen, SMP_CACHE_BYTES); 631 if (!saved_command_line) 632 panic("%s: Failed to allocate %zu bytes\n", __func__, len + ilen); 633 634 static_command_line = memblock_alloc(len, SMP_CACHE_BYTES); 635 if (!static_command_line) 636 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 637 638 if (xlen) { 639 /* 640 * We have to put extra_command_line before boot command 641 * lines because there could be dashes (separator of init 642 * command line) in the command lines. 643 */ 644 strcpy(saved_command_line, extra_command_line); 645 strcpy(static_command_line, extra_command_line); 646 } 647 strcpy(saved_command_line + xlen, boot_command_line); 648 strcpy(static_command_line + xlen, command_line); 649 650 if (ilen) { 651 /* 652 * Append supplemental init boot args to saved_command_line 653 * so that user can check what command line options passed 654 * to init. 655 * The order should always be 656 * " -- "[bootconfig init-param][cmdline init-param] 657 */ 658 if (initargs_offs) { 659 len = xlen + initargs_offs; 660 strcpy(saved_command_line + len, extra_init_args); 661 len += ilen - 4; /* strlen(extra_init_args) */ 662 strcpy(saved_command_line + len, 663 boot_command_line + initargs_offs - 1); 664 } else { 665 len = strlen(saved_command_line); 666 strcpy(saved_command_line + len, " -- "); 667 len += 4; 668 strcpy(saved_command_line + len, extra_init_args); 669 } 670 } 671 672 saved_command_line_len = strlen(saved_command_line); 673 } 674 675 /* 676 * We need to finalize in a non-__init function or else race conditions 677 * between the root thread and the init thread may cause start_kernel to 678 * be reaped by free_initmem before the root thread has proceeded to 679 * cpu_idle. 680 * 681 * gcc-3.4 accidentally inlines this function, so use noinline. 682 */ 683 684 static __initdata DECLARE_COMPLETION(kthreadd_done); 685 686 noinline void __ref rest_init(void) 687 { 688 struct task_struct *tsk; 689 int pid; 690 691 rcu_scheduler_starting(); 692 /* 693 * We need to spawn init first so that it obtains pid 1, however 694 * the init task will end up wanting to create kthreads, which, if 695 * we schedule it before we create kthreadd, will OOPS. 696 */ 697 pid = user_mode_thread(kernel_init, NULL, CLONE_FS); 698 /* 699 * Pin init on the boot CPU. Task migration is not properly working 700 * until sched_init_smp() has been run. It will set the allowed 701 * CPUs for init to the non isolated CPUs. 702 */ 703 rcu_read_lock(); 704 tsk = find_task_by_pid_ns(pid, &init_pid_ns); 705 tsk->flags |= PF_NO_SETAFFINITY; 706 set_cpus_allowed_ptr(tsk, cpumask_of(smp_processor_id())); 707 rcu_read_unlock(); 708 709 numa_default_policy(); 710 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES); 711 rcu_read_lock(); 712 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns); 713 rcu_read_unlock(); 714 715 /* 716 * Enable might_sleep() and smp_processor_id() checks. 717 * They cannot be enabled earlier because with CONFIG_PREEMPTION=y 718 * kernel_thread() would trigger might_sleep() splats. With 719 * CONFIG_PREEMPT_VOLUNTARY=y the init task might have scheduled 720 * already, but it's stuck on the kthreadd_done completion. 721 */ 722 system_state = SYSTEM_SCHEDULING; 723 724 complete(&kthreadd_done); 725 726 /* 727 * The boot idle thread must execute schedule() 728 * at least once to get things moving: 729 */ 730 schedule_preempt_disabled(); 731 /* Call into cpu_idle with preempt disabled */ 732 cpu_startup_entry(CPUHP_ONLINE); 733 } 734 735 /* Check for early params. */ 736 static int __init do_early_param(char *param, char *val, 737 const char *unused, void *arg) 738 { 739 const struct obs_kernel_param *p; 740 741 for (p = __setup_start; p < __setup_end; p++) { 742 if ((p->early && parameq(param, p->str)) || 743 (strcmp(param, "console") == 0 && 744 strcmp(p->str, "earlycon") == 0) 745 ) { 746 if (p->setup_func(val) != 0) 747 pr_warn("Malformed early option '%s'\n", param); 748 } 749 } 750 /* We accept everything at this stage. */ 751 return 0; 752 } 753 754 void __init parse_early_options(char *cmdline) 755 { 756 parse_args("early options", cmdline, NULL, 0, 0, 0, NULL, 757 do_early_param); 758 } 759 760 /* Arch code calls this early on, or if not, just before other parsing. */ 761 void __init parse_early_param(void) 762 { 763 static int done __initdata; 764 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; 765 766 if (done) 767 return; 768 769 /* All fall through to do_early_param. */ 770 strscpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); 771 parse_early_options(tmp_cmdline); 772 done = 1; 773 } 774 775 void __init __weak arch_post_acpi_subsys_init(void) { } 776 777 void __init __weak smp_setup_processor_id(void) 778 { 779 } 780 781 # if THREAD_SIZE >= PAGE_SIZE 782 void __init __weak thread_stack_cache_init(void) 783 { 784 } 785 #endif 786 787 void __init __weak mem_encrypt_init(void) { } 788 789 void __init __weak poking_init(void) { } 790 791 void __init __weak pgtable_cache_init(void) { } 792 793 void __init __weak trap_init(void) { } 794 795 bool initcall_debug; 796 core_param(initcall_debug, initcall_debug, bool, 0644); 797 798 #ifdef TRACEPOINTS_ENABLED 799 static void __init initcall_debug_enable(void); 800 #else 801 static inline void initcall_debug_enable(void) 802 { 803 } 804 #endif 805 806 /* Report memory auto-initialization states for this boot. */ 807 static void __init report_meminit(void) 808 { 809 const char *stack; 810 811 if (IS_ENABLED(CONFIG_INIT_STACK_ALL_PATTERN)) 812 stack = "all(pattern)"; 813 else if (IS_ENABLED(CONFIG_INIT_STACK_ALL_ZERO)) 814 stack = "all(zero)"; 815 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL)) 816 stack = "byref_all(zero)"; 817 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF)) 818 stack = "byref(zero)"; 819 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_USER)) 820 stack = "__user(zero)"; 821 else 822 stack = "off"; 823 824 pr_info("mem auto-init: stack:%s, heap alloc:%s, heap free:%s\n", 825 stack, want_init_on_alloc(GFP_KERNEL) ? "on" : "off", 826 want_init_on_free() ? "on" : "off"); 827 if (want_init_on_free()) 828 pr_info("mem auto-init: clearing system memory may take some time...\n"); 829 } 830 831 /* 832 * Set up kernel memory allocators 833 */ 834 static void __init mm_init(void) 835 { 836 /* 837 * page_ext requires contiguous pages, 838 * bigger than MAX_ORDER unless SPARSEMEM. 839 */ 840 page_ext_init_flatmem(); 841 init_mem_debugging_and_hardening(); 842 kfence_alloc_pool(); 843 report_meminit(); 844 kmsan_init_shadow(); 845 stack_depot_early_init(); 846 mem_init(); 847 mem_init_print_info(); 848 kmem_cache_init(); 849 /* 850 * page_owner must be initialized after buddy is ready, and also after 851 * slab is ready so that stack_depot_init() works properly 852 */ 853 page_ext_init_flatmem_late(); 854 kmemleak_init(); 855 pgtable_init(); 856 debug_objects_mem_init(); 857 vmalloc_init(); 858 /* Should be run after vmap initialization */ 859 if (early_page_ext_enabled()) 860 page_ext_init(); 861 /* Should be run before the first non-init thread is created */ 862 init_espfix_bsp(); 863 /* Should be run after espfix64 is set up. */ 864 pti_init(); 865 kmsan_init_runtime(); 866 mm_cache_init(); 867 } 868 869 #ifdef CONFIG_RANDOMIZE_KSTACK_OFFSET 870 DEFINE_STATIC_KEY_MAYBE_RO(CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT, 871 randomize_kstack_offset); 872 DEFINE_PER_CPU(u32, kstack_offset); 873 874 static int __init early_randomize_kstack_offset(char *buf) 875 { 876 int ret; 877 bool bool_result; 878 879 ret = kstrtobool(buf, &bool_result); 880 if (ret) 881 return ret; 882 883 if (bool_result) 884 static_branch_enable(&randomize_kstack_offset); 885 else 886 static_branch_disable(&randomize_kstack_offset); 887 return 0; 888 } 889 early_param("randomize_kstack_offset", early_randomize_kstack_offset); 890 #endif 891 892 void __init __weak arch_call_rest_init(void) 893 { 894 rest_init(); 895 } 896 897 static void __init print_unknown_bootoptions(void) 898 { 899 char *unknown_options; 900 char *end; 901 const char *const *p; 902 size_t len; 903 904 if (panic_later || (!argv_init[1] && !envp_init[2])) 905 return; 906 907 /* 908 * Determine how many options we have to print out, plus a space 909 * before each 910 */ 911 len = 1; /* null terminator */ 912 for (p = &argv_init[1]; *p; p++) { 913 len++; 914 len += strlen(*p); 915 } 916 for (p = &envp_init[2]; *p; p++) { 917 len++; 918 len += strlen(*p); 919 } 920 921 unknown_options = memblock_alloc(len, SMP_CACHE_BYTES); 922 if (!unknown_options) { 923 pr_err("%s: Failed to allocate %zu bytes\n", 924 __func__, len); 925 return; 926 } 927 end = unknown_options; 928 929 for (p = &argv_init[1]; *p; p++) 930 end += sprintf(end, " %s", *p); 931 for (p = &envp_init[2]; *p; p++) 932 end += sprintf(end, " %s", *p); 933 934 /* Start at unknown_options[1] to skip the initial space */ 935 pr_notice("Unknown kernel command line parameters \"%s\", will be passed to user space.\n", 936 &unknown_options[1]); 937 memblock_free(unknown_options, len); 938 } 939 940 asmlinkage __visible void __init __no_sanitize_address start_kernel(void) 941 { 942 char *command_line; 943 char *after_dashes; 944 945 set_task_stack_end_magic(&init_task); 946 smp_setup_processor_id(); 947 debug_objects_early_init(); 948 init_vmlinux_build_id(); 949 950 cgroup_init_early(); 951 952 local_irq_disable(); 953 early_boot_irqs_disabled = true; 954 955 /* 956 * Interrupts are still disabled. Do necessary setups, then 957 * enable them. 958 */ 959 boot_cpu_init(); 960 page_address_init(); 961 pr_notice("%s", linux_banner); 962 early_security_init(); 963 setup_arch(&command_line); 964 setup_boot_config(); 965 setup_command_line(command_line); 966 setup_nr_cpu_ids(); 967 setup_per_cpu_areas(); 968 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */ 969 boot_cpu_hotplug_init(); 970 971 build_all_zonelists(NULL); 972 page_alloc_init(); 973 974 pr_notice("Kernel command line: %s\n", saved_command_line); 975 /* parameters may set static keys */ 976 jump_label_init(); 977 parse_early_param(); 978 after_dashes = parse_args("Booting kernel", 979 static_command_line, __start___param, 980 __stop___param - __start___param, 981 -1, -1, NULL, &unknown_bootoption); 982 print_unknown_bootoptions(); 983 if (!IS_ERR_OR_NULL(after_dashes)) 984 parse_args("Setting init args", after_dashes, NULL, 0, -1, -1, 985 NULL, set_init_arg); 986 if (extra_init_args) 987 parse_args("Setting extra init args", extra_init_args, 988 NULL, 0, -1, -1, NULL, set_init_arg); 989 990 /* Architectural and non-timekeeping rng init, before allocator init */ 991 random_init_early(command_line); 992 993 /* 994 * These use large bootmem allocations and must precede 995 * kmem_cache_init() 996 */ 997 setup_log_buf(0); 998 vfs_caches_init_early(); 999 sort_main_extable(); 1000 trap_init(); 1001 mm_init(); 1002 poking_init(); 1003 ftrace_init(); 1004 1005 /* trace_printk can be enabled here */ 1006 early_trace_init(); 1007 1008 /* 1009 * Set up the scheduler prior starting any interrupts (such as the 1010 * timer interrupt). Full topology setup happens at smp_init() 1011 * time - but meanwhile we still have a functioning scheduler. 1012 */ 1013 sched_init(); 1014 1015 if (WARN(!irqs_disabled(), 1016 "Interrupts were enabled *very* early, fixing it\n")) 1017 local_irq_disable(); 1018 radix_tree_init(); 1019 maple_tree_init(); 1020 1021 /* 1022 * Set up housekeeping before setting up workqueues to allow the unbound 1023 * workqueue to take non-housekeeping into account. 1024 */ 1025 housekeeping_init(); 1026 1027 /* 1028 * Allow workqueue creation and work item queueing/cancelling 1029 * early. Work item execution depends on kthreads and starts after 1030 * workqueue_init(). 1031 */ 1032 workqueue_init_early(); 1033 1034 rcu_init(); 1035 1036 /* Trace events are available after this */ 1037 trace_init(); 1038 1039 if (initcall_debug) 1040 initcall_debug_enable(); 1041 1042 context_tracking_init(); 1043 /* init some links before init_ISA_irqs() */ 1044 early_irq_init(); 1045 init_IRQ(); 1046 tick_init(); 1047 rcu_init_nohz(); 1048 init_timers(); 1049 srcu_init(); 1050 hrtimers_init(); 1051 softirq_init(); 1052 timekeeping_init(); 1053 time_init(); 1054 1055 /* This must be after timekeeping is initialized */ 1056 random_init(); 1057 1058 /* These make use of the fully initialized rng */ 1059 kfence_init(); 1060 boot_init_stack_canary(); 1061 1062 perf_event_init(); 1063 profile_init(); 1064 call_function_init(); 1065 WARN(!irqs_disabled(), "Interrupts were enabled early\n"); 1066 1067 early_boot_irqs_disabled = false; 1068 local_irq_enable(); 1069 1070 kmem_cache_init_late(); 1071 1072 /* 1073 * HACK ALERT! This is early. We're enabling the console before 1074 * we've done PCI setups etc, and console_init() must be aware of 1075 * this. But we do want output early, in case something goes wrong. 1076 */ 1077 console_init(); 1078 if (panic_later) 1079 panic("Too many boot %s vars at `%s'", panic_later, 1080 panic_param); 1081 1082 lockdep_init(); 1083 1084 /* 1085 * Need to run this when irqs are enabled, because it wants 1086 * to self-test [hard/soft]-irqs on/off lock inversion bugs 1087 * too: 1088 */ 1089 locking_selftest(); 1090 1091 /* 1092 * This needs to be called before any devices perform DMA 1093 * operations that might use the SWIOTLB bounce buffers. It will 1094 * mark the bounce buffers as decrypted so that their usage will 1095 * not cause "plain-text" data to be decrypted when accessed. 1096 */ 1097 mem_encrypt_init(); 1098 1099 #ifdef CONFIG_BLK_DEV_INITRD 1100 if (initrd_start && !initrd_below_start_ok && 1101 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) { 1102 pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n", 1103 page_to_pfn(virt_to_page((void *)initrd_start)), 1104 min_low_pfn); 1105 initrd_start = 0; 1106 } 1107 #endif 1108 setup_per_cpu_pageset(); 1109 numa_policy_init(); 1110 acpi_early_init(); 1111 if (late_time_init) 1112 late_time_init(); 1113 sched_clock_init(); 1114 calibrate_delay(); 1115 pid_idr_init(); 1116 anon_vma_init(); 1117 #ifdef CONFIG_X86 1118 if (efi_enabled(EFI_RUNTIME_SERVICES)) 1119 efi_enter_virtual_mode(); 1120 #endif 1121 thread_stack_cache_init(); 1122 cred_init(); 1123 fork_init(); 1124 proc_caches_init(); 1125 uts_ns_init(); 1126 key_init(); 1127 security_init(); 1128 dbg_late_init(); 1129 net_ns_init(); 1130 vfs_caches_init(); 1131 pagecache_init(); 1132 signals_init(); 1133 seq_file_init(); 1134 proc_root_init(); 1135 nsfs_init(); 1136 cpuset_init(); 1137 cgroup_init(); 1138 taskstats_init_early(); 1139 delayacct_init(); 1140 1141 check_bugs(); 1142 1143 acpi_subsystem_init(); 1144 arch_post_acpi_subsys_init(); 1145 kcsan_init(); 1146 1147 /* Do the rest non-__init'ed, we're now alive */ 1148 arch_call_rest_init(); 1149 1150 prevent_tail_call_optimization(); 1151 } 1152 1153 /* Call all constructor functions linked into the kernel. */ 1154 static void __init do_ctors(void) 1155 { 1156 /* 1157 * For UML, the constructors have already been called by the 1158 * normal setup code as it's just a normal ELF binary, so we 1159 * cannot do it again - but we do need CONFIG_CONSTRUCTORS 1160 * even on UML for modules. 1161 */ 1162 #if defined(CONFIG_CONSTRUCTORS) && !defined(CONFIG_UML) 1163 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start; 1164 1165 for (; fn < (ctor_fn_t *) __ctors_end; fn++) 1166 (*fn)(); 1167 #endif 1168 } 1169 1170 #ifdef CONFIG_KALLSYMS 1171 struct blacklist_entry { 1172 struct list_head next; 1173 char *buf; 1174 }; 1175 1176 static __initdata_or_module LIST_HEAD(blacklisted_initcalls); 1177 1178 static int __init initcall_blacklist(char *str) 1179 { 1180 char *str_entry; 1181 struct blacklist_entry *entry; 1182 1183 /* str argument is a comma-separated list of functions */ 1184 do { 1185 str_entry = strsep(&str, ","); 1186 if (str_entry) { 1187 pr_debug("blacklisting initcall %s\n", str_entry); 1188 entry = memblock_alloc(sizeof(*entry), 1189 SMP_CACHE_BYTES); 1190 if (!entry) 1191 panic("%s: Failed to allocate %zu bytes\n", 1192 __func__, sizeof(*entry)); 1193 entry->buf = memblock_alloc(strlen(str_entry) + 1, 1194 SMP_CACHE_BYTES); 1195 if (!entry->buf) 1196 panic("%s: Failed to allocate %zu bytes\n", 1197 __func__, strlen(str_entry) + 1); 1198 strcpy(entry->buf, str_entry); 1199 list_add(&entry->next, &blacklisted_initcalls); 1200 } 1201 } while (str_entry); 1202 1203 return 1; 1204 } 1205 1206 static bool __init_or_module initcall_blacklisted(initcall_t fn) 1207 { 1208 struct blacklist_entry *entry; 1209 char fn_name[KSYM_SYMBOL_LEN]; 1210 unsigned long addr; 1211 1212 if (list_empty(&blacklisted_initcalls)) 1213 return false; 1214 1215 addr = (unsigned long) dereference_function_descriptor(fn); 1216 sprint_symbol_no_offset(fn_name, addr); 1217 1218 /* 1219 * fn will be "function_name [module_name]" where [module_name] is not 1220 * displayed for built-in init functions. Strip off the [module_name]. 1221 */ 1222 strreplace(fn_name, ' ', '\0'); 1223 1224 list_for_each_entry(entry, &blacklisted_initcalls, next) { 1225 if (!strcmp(fn_name, entry->buf)) { 1226 pr_debug("initcall %s blacklisted\n", fn_name); 1227 return true; 1228 } 1229 } 1230 1231 return false; 1232 } 1233 #else 1234 static int __init initcall_blacklist(char *str) 1235 { 1236 pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n"); 1237 return 0; 1238 } 1239 1240 static bool __init_or_module initcall_blacklisted(initcall_t fn) 1241 { 1242 return false; 1243 } 1244 #endif 1245 __setup("initcall_blacklist=", initcall_blacklist); 1246 1247 static __init_or_module void 1248 trace_initcall_start_cb(void *data, initcall_t fn) 1249 { 1250 ktime_t *calltime = data; 1251 1252 printk(KERN_DEBUG "calling %pS @ %i\n", fn, task_pid_nr(current)); 1253 *calltime = ktime_get(); 1254 } 1255 1256 static __init_or_module void 1257 trace_initcall_finish_cb(void *data, initcall_t fn, int ret) 1258 { 1259 ktime_t rettime, *calltime = data; 1260 1261 rettime = ktime_get(); 1262 printk(KERN_DEBUG "initcall %pS returned %d after %lld usecs\n", 1263 fn, ret, (unsigned long long)ktime_us_delta(rettime, *calltime)); 1264 } 1265 1266 static ktime_t initcall_calltime; 1267 1268 #ifdef TRACEPOINTS_ENABLED 1269 static void __init initcall_debug_enable(void) 1270 { 1271 int ret; 1272 1273 ret = register_trace_initcall_start(trace_initcall_start_cb, 1274 &initcall_calltime); 1275 ret |= register_trace_initcall_finish(trace_initcall_finish_cb, 1276 &initcall_calltime); 1277 WARN(ret, "Failed to register initcall tracepoints\n"); 1278 } 1279 # define do_trace_initcall_start trace_initcall_start 1280 # define do_trace_initcall_finish trace_initcall_finish 1281 #else 1282 static inline void do_trace_initcall_start(initcall_t fn) 1283 { 1284 if (!initcall_debug) 1285 return; 1286 trace_initcall_start_cb(&initcall_calltime, fn); 1287 } 1288 static inline void do_trace_initcall_finish(initcall_t fn, int ret) 1289 { 1290 if (!initcall_debug) 1291 return; 1292 trace_initcall_finish_cb(&initcall_calltime, fn, ret); 1293 } 1294 #endif /* !TRACEPOINTS_ENABLED */ 1295 1296 int __init_or_module do_one_initcall(initcall_t fn) 1297 { 1298 int count = preempt_count(); 1299 char msgbuf[64]; 1300 int ret; 1301 1302 if (initcall_blacklisted(fn)) 1303 return -EPERM; 1304 1305 do_trace_initcall_start(fn); 1306 ret = fn(); 1307 do_trace_initcall_finish(fn, ret); 1308 1309 msgbuf[0] = 0; 1310 1311 if (preempt_count() != count) { 1312 sprintf(msgbuf, "preemption imbalance "); 1313 preempt_count_set(count); 1314 } 1315 if (irqs_disabled()) { 1316 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf)); 1317 local_irq_enable(); 1318 } 1319 WARN(msgbuf[0], "initcall %pS returned with %s\n", fn, msgbuf); 1320 1321 add_latent_entropy(); 1322 return ret; 1323 } 1324 1325 1326 extern initcall_entry_t __initcall_start[]; 1327 extern initcall_entry_t __initcall0_start[]; 1328 extern initcall_entry_t __initcall1_start[]; 1329 extern initcall_entry_t __initcall2_start[]; 1330 extern initcall_entry_t __initcall3_start[]; 1331 extern initcall_entry_t __initcall4_start[]; 1332 extern initcall_entry_t __initcall5_start[]; 1333 extern initcall_entry_t __initcall6_start[]; 1334 extern initcall_entry_t __initcall7_start[]; 1335 extern initcall_entry_t __initcall_end[]; 1336 1337 static initcall_entry_t *initcall_levels[] __initdata = { 1338 __initcall0_start, 1339 __initcall1_start, 1340 __initcall2_start, 1341 __initcall3_start, 1342 __initcall4_start, 1343 __initcall5_start, 1344 __initcall6_start, 1345 __initcall7_start, 1346 __initcall_end, 1347 }; 1348 1349 /* Keep these in sync with initcalls in include/linux/init.h */ 1350 static const char *initcall_level_names[] __initdata = { 1351 "pure", 1352 "core", 1353 "postcore", 1354 "arch", 1355 "subsys", 1356 "fs", 1357 "device", 1358 "late", 1359 }; 1360 1361 static int __init ignore_unknown_bootoption(char *param, char *val, 1362 const char *unused, void *arg) 1363 { 1364 return 0; 1365 } 1366 1367 static void __init do_initcall_level(int level, char *command_line) 1368 { 1369 initcall_entry_t *fn; 1370 1371 parse_args(initcall_level_names[level], 1372 command_line, __start___param, 1373 __stop___param - __start___param, 1374 level, level, 1375 NULL, ignore_unknown_bootoption); 1376 1377 trace_initcall_level(initcall_level_names[level]); 1378 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++) 1379 do_one_initcall(initcall_from_entry(fn)); 1380 } 1381 1382 static void __init do_initcalls(void) 1383 { 1384 int level; 1385 size_t len = saved_command_line_len + 1; 1386 char *command_line; 1387 1388 command_line = kzalloc(len, GFP_KERNEL); 1389 if (!command_line) 1390 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 1391 1392 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) { 1393 /* Parser modifies command_line, restore it each time */ 1394 strcpy(command_line, saved_command_line); 1395 do_initcall_level(level, command_line); 1396 } 1397 1398 kfree(command_line); 1399 } 1400 1401 /* 1402 * Ok, the machine is now initialized. None of the devices 1403 * have been touched yet, but the CPU subsystem is up and 1404 * running, and memory and process management works. 1405 * 1406 * Now we can finally start doing some real work.. 1407 */ 1408 static void __init do_basic_setup(void) 1409 { 1410 cpuset_init_smp(); 1411 driver_init(); 1412 init_irq_proc(); 1413 do_ctors(); 1414 do_initcalls(); 1415 } 1416 1417 static void __init do_pre_smp_initcalls(void) 1418 { 1419 initcall_entry_t *fn; 1420 1421 trace_initcall_level("early"); 1422 for (fn = __initcall_start; fn < __initcall0_start; fn++) 1423 do_one_initcall(initcall_from_entry(fn)); 1424 } 1425 1426 static int run_init_process(const char *init_filename) 1427 { 1428 const char *const *p; 1429 1430 argv_init[0] = init_filename; 1431 pr_info("Run %s as init process\n", init_filename); 1432 pr_debug(" with arguments:\n"); 1433 for (p = argv_init; *p; p++) 1434 pr_debug(" %s\n", *p); 1435 pr_debug(" with environment:\n"); 1436 for (p = envp_init; *p; p++) 1437 pr_debug(" %s\n", *p); 1438 return kernel_execve(init_filename, argv_init, envp_init); 1439 } 1440 1441 static int try_to_run_init_process(const char *init_filename) 1442 { 1443 int ret; 1444 1445 ret = run_init_process(init_filename); 1446 1447 if (ret && ret != -ENOENT) { 1448 pr_err("Starting init: %s exists but couldn't execute it (error %d)\n", 1449 init_filename, ret); 1450 } 1451 1452 return ret; 1453 } 1454 1455 static noinline void __init kernel_init_freeable(void); 1456 1457 #if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX) 1458 bool rodata_enabled __ro_after_init = true; 1459 1460 #ifndef arch_parse_debug_rodata 1461 static inline bool arch_parse_debug_rodata(char *str) { return false; } 1462 #endif 1463 1464 static int __init set_debug_rodata(char *str) 1465 { 1466 if (arch_parse_debug_rodata(str)) 1467 return 0; 1468 1469 if (str && !strcmp(str, "on")) 1470 rodata_enabled = true; 1471 else if (str && !strcmp(str, "off")) 1472 rodata_enabled = false; 1473 else 1474 pr_warn("Invalid option string for rodata: '%s'\n", str); 1475 return 0; 1476 } 1477 early_param("rodata", set_debug_rodata); 1478 #endif 1479 1480 #ifdef CONFIG_STRICT_KERNEL_RWX 1481 static void mark_readonly(void) 1482 { 1483 if (rodata_enabled) { 1484 /* 1485 * load_module() results in W+X mappings, which are cleaned 1486 * up with call_rcu(). Let's make sure that queued work is 1487 * flushed so that we don't hit false positives looking for 1488 * insecure pages which are W+X. 1489 */ 1490 rcu_barrier(); 1491 mark_rodata_ro(); 1492 rodata_test(); 1493 } else 1494 pr_info("Kernel memory protection disabled.\n"); 1495 } 1496 #elif defined(CONFIG_ARCH_HAS_STRICT_KERNEL_RWX) 1497 static inline void mark_readonly(void) 1498 { 1499 pr_warn("Kernel memory protection not selected by kernel config.\n"); 1500 } 1501 #else 1502 static inline void mark_readonly(void) 1503 { 1504 pr_warn("This architecture does not have kernel memory protection.\n"); 1505 } 1506 #endif 1507 1508 void __weak free_initmem(void) 1509 { 1510 free_initmem_default(POISON_FREE_INITMEM); 1511 } 1512 1513 static int __ref kernel_init(void *unused) 1514 { 1515 int ret; 1516 1517 /* 1518 * Wait until kthreadd is all set-up. 1519 */ 1520 wait_for_completion(&kthreadd_done); 1521 1522 kernel_init_freeable(); 1523 /* need to finish all async __init code before freeing the memory */ 1524 async_synchronize_full(); 1525 1526 system_state = SYSTEM_FREEING_INITMEM; 1527 kprobe_free_init_mem(); 1528 ftrace_free_init_mem(); 1529 kgdb_free_init_mem(); 1530 exit_boot_config(); 1531 free_initmem(); 1532 mark_readonly(); 1533 1534 /* 1535 * Kernel mappings are now finalized - update the userspace page-table 1536 * to finalize PTI. 1537 */ 1538 pti_finalize(); 1539 1540 system_state = SYSTEM_RUNNING; 1541 numa_default_policy(); 1542 1543 rcu_end_inkernel_boot(); 1544 1545 do_sysctl_args(); 1546 1547 if (ramdisk_execute_command) { 1548 ret = run_init_process(ramdisk_execute_command); 1549 if (!ret) 1550 return 0; 1551 pr_err("Failed to execute %s (error %d)\n", 1552 ramdisk_execute_command, ret); 1553 } 1554 1555 /* 1556 * We try each of these until one succeeds. 1557 * 1558 * The Bourne shell can be used instead of init if we are 1559 * trying to recover a really broken machine. 1560 */ 1561 if (execute_command) { 1562 ret = run_init_process(execute_command); 1563 if (!ret) 1564 return 0; 1565 panic("Requested init %s failed (error %d).", 1566 execute_command, ret); 1567 } 1568 1569 if (CONFIG_DEFAULT_INIT[0] != '\0') { 1570 ret = run_init_process(CONFIG_DEFAULT_INIT); 1571 if (ret) 1572 pr_err("Default init %s failed (error %d)\n", 1573 CONFIG_DEFAULT_INIT, ret); 1574 else 1575 return 0; 1576 } 1577 1578 if (!try_to_run_init_process("/sbin/init") || 1579 !try_to_run_init_process("/etc/init") || 1580 !try_to_run_init_process("/bin/init") || 1581 !try_to_run_init_process("/bin/sh")) 1582 return 0; 1583 1584 panic("No working init found. Try passing init= option to kernel. " 1585 "See Linux Documentation/admin-guide/init.rst for guidance."); 1586 } 1587 1588 /* Open /dev/console, for stdin/stdout/stderr, this should never fail */ 1589 void __init console_on_rootfs(void) 1590 { 1591 struct file *file = filp_open("/dev/console", O_RDWR, 0); 1592 1593 if (IS_ERR(file)) { 1594 pr_err("Warning: unable to open an initial console.\n"); 1595 return; 1596 } 1597 init_dup(file); 1598 init_dup(file); 1599 init_dup(file); 1600 fput(file); 1601 } 1602 1603 static noinline void __init kernel_init_freeable(void) 1604 { 1605 /* Now the scheduler is fully set up and can do blocking allocations */ 1606 gfp_allowed_mask = __GFP_BITS_MASK; 1607 1608 /* 1609 * init can allocate pages on any node 1610 */ 1611 set_mems_allowed(node_states[N_MEMORY]); 1612 1613 cad_pid = get_pid(task_pid(current)); 1614 1615 smp_prepare_cpus(setup_max_cpus); 1616 1617 workqueue_init(); 1618 1619 init_mm_internals(); 1620 1621 rcu_init_tasks_generic(); 1622 do_pre_smp_initcalls(); 1623 lockup_detector_init(); 1624 1625 smp_init(); 1626 sched_init_smp(); 1627 1628 padata_init(); 1629 page_alloc_init_late(); 1630 /* Initialize page ext after all struct pages are initialized. */ 1631 if (!early_page_ext_enabled()) 1632 page_ext_init(); 1633 1634 do_basic_setup(); 1635 1636 kunit_run_all_tests(); 1637 1638 wait_for_initramfs(); 1639 console_on_rootfs(); 1640 1641 /* 1642 * check if there is an early userspace init. If yes, let it do all 1643 * the work 1644 */ 1645 if (init_eaccess(ramdisk_execute_command) != 0) { 1646 ramdisk_execute_command = NULL; 1647 prepare_namespace(); 1648 } 1649 1650 /* 1651 * Ok, we have completed the initial bootup, and 1652 * we're essentially up and running. Get rid of the 1653 * initmem segments and start the user-mode stuff.. 1654 * 1655 * rootfs is available now, try loading the public keys 1656 * and default modules 1657 */ 1658 1659 integrity_load_keys(); 1660 } 1661