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/console.h> 32 #include <linux/nmi.h> 33 #include <linux/percpu.h> 34 #include <linux/kmod.h> 35 #include <linux/vmalloc.h> 36 #include <linux/kernel_stat.h> 37 #include <linux/start_kernel.h> 38 #include <linux/security.h> 39 #include <linux/smp.h> 40 #include <linux/profile.h> 41 #include <linux/rcupdate.h> 42 #include <linux/moduleparam.h> 43 #include <linux/kallsyms.h> 44 #include <linux/writeback.h> 45 #include <linux/cpu.h> 46 #include <linux/cpuset.h> 47 #include <linux/cgroup.h> 48 #include <linux/efi.h> 49 #include <linux/tick.h> 50 #include <linux/sched/isolation.h> 51 #include <linux/interrupt.h> 52 #include <linux/taskstats_kern.h> 53 #include <linux/delayacct.h> 54 #include <linux/unistd.h> 55 #include <linux/utsname.h> 56 #include <linux/rmap.h> 57 #include <linux/mempolicy.h> 58 #include <linux/key.h> 59 #include <linux/buffer_head.h> 60 #include <linux/page_ext.h> 61 #include <linux/debug_locks.h> 62 #include <linux/debugobjects.h> 63 #include <linux/lockdep.h> 64 #include <linux/kmemleak.h> 65 #include <linux/pid_namespace.h> 66 #include <linux/device.h> 67 #include <linux/kthread.h> 68 #include <linux/sched.h> 69 #include <linux/sched/init.h> 70 #include <linux/signal.h> 71 #include <linux/idr.h> 72 #include <linux/kgdb.h> 73 #include <linux/ftrace.h> 74 #include <linux/async.h> 75 #include <linux/sfi.h> 76 #include <linux/shmem_fs.h> 77 #include <linux/slab.h> 78 #include <linux/perf_event.h> 79 #include <linux/ptrace.h> 80 #include <linux/pti.h> 81 #include <linux/blkdev.h> 82 #include <linux/elevator.h> 83 #include <linux/sched/clock.h> 84 #include <linux/sched/task.h> 85 #include <linux/sched/task_stack.h> 86 #include <linux/context_tracking.h> 87 #include <linux/random.h> 88 #include <linux/list.h> 89 #include <linux/integrity.h> 90 #include <linux/proc_ns.h> 91 #include <linux/io.h> 92 #include <linux/cache.h> 93 #include <linux/rodata_test.h> 94 #include <linux/jump_label.h> 95 #include <linux/mem_encrypt.h> 96 #include <linux/file.h> 97 98 #include <asm/io.h> 99 #include <asm/bugs.h> 100 #include <asm/setup.h> 101 #include <asm/sections.h> 102 #include <asm/cacheflush.h> 103 104 #define CREATE_TRACE_POINTS 105 #include <trace/events/initcall.h> 106 107 static int kernel_init(void *); 108 109 extern void init_IRQ(void); 110 extern void radix_tree_init(void); 111 112 /* 113 * Debug helper: via this flag we know that we are in 'early bootup code' 114 * where only the boot processor is running with IRQ disabled. This means 115 * two things - IRQ must not be enabled before the flag is cleared and some 116 * operations which are not allowed with IRQ disabled are allowed while the 117 * flag is set. 118 */ 119 bool early_boot_irqs_disabled __read_mostly; 120 121 enum system_states system_state __read_mostly; 122 EXPORT_SYMBOL(system_state); 123 124 /* 125 * Boot command-line arguments 126 */ 127 #define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT 128 #define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT 129 130 extern void time_init(void); 131 /* Default late time init is NULL. archs can override this later. */ 132 void (*__initdata late_time_init)(void); 133 134 /* Untouched command line saved by arch-specific code. */ 135 char __initdata boot_command_line[COMMAND_LINE_SIZE]; 136 /* Untouched saved command line (eg. for /proc) */ 137 char *saved_command_line; 138 /* Command line for parameter parsing */ 139 static char *static_command_line; 140 /* Command line for per-initcall parameter parsing */ 141 static char *initcall_command_line; 142 143 static char *execute_command; 144 static char *ramdisk_execute_command; 145 146 /* 147 * Used to generate warnings if static_key manipulation functions are used 148 * before jump_label_init is called. 149 */ 150 bool static_key_initialized __read_mostly; 151 EXPORT_SYMBOL_GPL(static_key_initialized); 152 153 /* 154 * If set, this is an indication to the drivers that reset the underlying 155 * device before going ahead with the initialization otherwise driver might 156 * rely on the BIOS and skip the reset operation. 157 * 158 * This is useful if kernel is booting in an unreliable environment. 159 * For ex. kdump situation where previous kernel has crashed, BIOS has been 160 * skipped and devices will be in unknown state. 161 */ 162 unsigned int reset_devices; 163 EXPORT_SYMBOL(reset_devices); 164 165 static int __init set_reset_devices(char *str) 166 { 167 reset_devices = 1; 168 return 1; 169 } 170 171 __setup("reset_devices", set_reset_devices); 172 173 static const char *argv_init[MAX_INIT_ARGS+2] = { "init", NULL, }; 174 const char *envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, }; 175 static const char *panic_later, *panic_param; 176 177 extern const struct obs_kernel_param __setup_start[], __setup_end[]; 178 179 static bool __init obsolete_checksetup(char *line) 180 { 181 const struct obs_kernel_param *p; 182 bool had_early_param = false; 183 184 p = __setup_start; 185 do { 186 int n = strlen(p->str); 187 if (parameqn(line, p->str, n)) { 188 if (p->early) { 189 /* Already done in parse_early_param? 190 * (Needs exact match on param part). 191 * Keep iterating, as we can have early 192 * params and __setups of same names 8( */ 193 if (line[n] == '\0' || line[n] == '=') 194 had_early_param = true; 195 } else if (!p->setup_func) { 196 pr_warn("Parameter %s is obsolete, ignored\n", 197 p->str); 198 return true; 199 } else if (p->setup_func(line + n)) 200 return true; 201 } 202 p++; 203 } while (p < __setup_end); 204 205 return had_early_param; 206 } 207 208 /* 209 * This should be approx 2 Bo*oMips to start (note initial shift), and will 210 * still work even if initially too large, it will just take slightly longer 211 */ 212 unsigned long loops_per_jiffy = (1<<12); 213 EXPORT_SYMBOL(loops_per_jiffy); 214 215 static int __init debug_kernel(char *str) 216 { 217 console_loglevel = CONSOLE_LOGLEVEL_DEBUG; 218 return 0; 219 } 220 221 static int __init quiet_kernel(char *str) 222 { 223 console_loglevel = CONSOLE_LOGLEVEL_QUIET; 224 return 0; 225 } 226 227 early_param("debug", debug_kernel); 228 early_param("quiet", quiet_kernel); 229 230 static int __init loglevel(char *str) 231 { 232 int newlevel; 233 234 /* 235 * Only update loglevel value when a correct setting was passed, 236 * to prevent blind crashes (when loglevel being set to 0) that 237 * are quite hard to debug 238 */ 239 if (get_option(&str, &newlevel)) { 240 console_loglevel = newlevel; 241 return 0; 242 } 243 244 return -EINVAL; 245 } 246 247 early_param("loglevel", loglevel); 248 249 /* Change NUL term back to "=", to make "param" the whole string. */ 250 static int __init repair_env_string(char *param, char *val, 251 const char *unused, void *arg) 252 { 253 if (val) { 254 /* param=val or param="val"? */ 255 if (val == param+strlen(param)+1) 256 val[-1] = '='; 257 else if (val == param+strlen(param)+2) { 258 val[-2] = '='; 259 memmove(val-1, val, strlen(val)+1); 260 val--; 261 } else 262 BUG(); 263 } 264 return 0; 265 } 266 267 /* Anything after -- gets handed straight to init. */ 268 static int __init set_init_arg(char *param, char *val, 269 const char *unused, void *arg) 270 { 271 unsigned int i; 272 273 if (panic_later) 274 return 0; 275 276 repair_env_string(param, val, unused, NULL); 277 278 for (i = 0; argv_init[i]; i++) { 279 if (i == MAX_INIT_ARGS) { 280 panic_later = "init"; 281 panic_param = param; 282 return 0; 283 } 284 } 285 argv_init[i] = param; 286 return 0; 287 } 288 289 /* 290 * Unknown boot options get handed to init, unless they look like 291 * unused parameters (modprobe will find them in /proc/cmdline). 292 */ 293 static int __init unknown_bootoption(char *param, char *val, 294 const char *unused, void *arg) 295 { 296 repair_env_string(param, val, unused, NULL); 297 298 /* Handle obsolete-style parameters */ 299 if (obsolete_checksetup(param)) 300 return 0; 301 302 /* Unused module parameter. */ 303 if (strchr(param, '.') && (!val || strchr(param, '.') < val)) 304 return 0; 305 306 if (panic_later) 307 return 0; 308 309 if (val) { 310 /* Environment option */ 311 unsigned int i; 312 for (i = 0; envp_init[i]; i++) { 313 if (i == MAX_INIT_ENVS) { 314 panic_later = "env"; 315 panic_param = param; 316 } 317 if (!strncmp(param, envp_init[i], val - param)) 318 break; 319 } 320 envp_init[i] = param; 321 } else { 322 /* Command line option */ 323 unsigned int i; 324 for (i = 0; argv_init[i]; i++) { 325 if (i == MAX_INIT_ARGS) { 326 panic_later = "init"; 327 panic_param = param; 328 } 329 } 330 argv_init[i] = param; 331 } 332 return 0; 333 } 334 335 static int __init init_setup(char *str) 336 { 337 unsigned int i; 338 339 execute_command = str; 340 /* 341 * In case LILO is going to boot us with default command line, 342 * it prepends "auto" before the whole cmdline which makes 343 * the shell think it should execute a script with such name. 344 * So we ignore all arguments entered _before_ init=... [MJ] 345 */ 346 for (i = 1; i < MAX_INIT_ARGS; i++) 347 argv_init[i] = NULL; 348 return 1; 349 } 350 __setup("init=", init_setup); 351 352 static int __init rdinit_setup(char *str) 353 { 354 unsigned int i; 355 356 ramdisk_execute_command = str; 357 /* See "auto" comment in init_setup */ 358 for (i = 1; i < MAX_INIT_ARGS; i++) 359 argv_init[i] = NULL; 360 return 1; 361 } 362 __setup("rdinit=", rdinit_setup); 363 364 #ifndef CONFIG_SMP 365 static const unsigned int setup_max_cpus = NR_CPUS; 366 static inline void setup_nr_cpu_ids(void) { } 367 static inline void smp_prepare_cpus(unsigned int maxcpus) { } 368 #endif 369 370 /* 371 * We need to store the untouched command line for future reference. 372 * We also need to store the touched command line since the parameter 373 * parsing is performed in place, and we should allow a component to 374 * store reference of name/value for future reference. 375 */ 376 static void __init setup_command_line(char *command_line) 377 { 378 size_t len = strlen(boot_command_line) + 1; 379 380 saved_command_line = memblock_alloc(len, SMP_CACHE_BYTES); 381 if (!saved_command_line) 382 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 383 384 initcall_command_line = memblock_alloc(len, SMP_CACHE_BYTES); 385 if (!initcall_command_line) 386 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 387 388 static_command_line = memblock_alloc(len, SMP_CACHE_BYTES); 389 if (!static_command_line) 390 panic("%s: Failed to allocate %zu bytes\n", __func__, len); 391 392 strcpy(saved_command_line, boot_command_line); 393 strcpy(static_command_line, command_line); 394 } 395 396 /* 397 * We need to finalize in a non-__init function or else race conditions 398 * between the root thread and the init thread may cause start_kernel to 399 * be reaped by free_initmem before the root thread has proceeded to 400 * cpu_idle. 401 * 402 * gcc-3.4 accidentally inlines this function, so use noinline. 403 */ 404 405 static __initdata DECLARE_COMPLETION(kthreadd_done); 406 407 noinline void __ref rest_init(void) 408 { 409 struct task_struct *tsk; 410 int pid; 411 412 rcu_scheduler_starting(); 413 /* 414 * We need to spawn init first so that it obtains pid 1, however 415 * the init task will end up wanting to create kthreads, which, if 416 * we schedule it before we create kthreadd, will OOPS. 417 */ 418 pid = kernel_thread(kernel_init, NULL, CLONE_FS); 419 /* 420 * Pin init on the boot CPU. Task migration is not properly working 421 * until sched_init_smp() has been run. It will set the allowed 422 * CPUs for init to the non isolated CPUs. 423 */ 424 rcu_read_lock(); 425 tsk = find_task_by_pid_ns(pid, &init_pid_ns); 426 set_cpus_allowed_ptr(tsk, cpumask_of(smp_processor_id())); 427 rcu_read_unlock(); 428 429 numa_default_policy(); 430 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES); 431 rcu_read_lock(); 432 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns); 433 rcu_read_unlock(); 434 435 /* 436 * Enable might_sleep() and smp_processor_id() checks. 437 * They cannot be enabled earlier because with CONFIG_PREEMPTION=y 438 * kernel_thread() would trigger might_sleep() splats. With 439 * CONFIG_PREEMPT_VOLUNTARY=y the init task might have scheduled 440 * already, but it's stuck on the kthreadd_done completion. 441 */ 442 system_state = SYSTEM_SCHEDULING; 443 444 complete(&kthreadd_done); 445 446 /* 447 * The boot idle thread must execute schedule() 448 * at least once to get things moving: 449 */ 450 schedule_preempt_disabled(); 451 /* Call into cpu_idle with preempt disabled */ 452 cpu_startup_entry(CPUHP_ONLINE); 453 } 454 455 /* Check for early params. */ 456 static int __init do_early_param(char *param, char *val, 457 const char *unused, void *arg) 458 { 459 const struct obs_kernel_param *p; 460 461 for (p = __setup_start; p < __setup_end; p++) { 462 if ((p->early && parameq(param, p->str)) || 463 (strcmp(param, "console") == 0 && 464 strcmp(p->str, "earlycon") == 0) 465 ) { 466 if (p->setup_func(val) != 0) 467 pr_warn("Malformed early option '%s'\n", param); 468 } 469 } 470 /* We accept everything at this stage. */ 471 return 0; 472 } 473 474 void __init parse_early_options(char *cmdline) 475 { 476 parse_args("early options", cmdline, NULL, 0, 0, 0, NULL, 477 do_early_param); 478 } 479 480 /* Arch code calls this early on, or if not, just before other parsing. */ 481 void __init parse_early_param(void) 482 { 483 static int done __initdata; 484 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; 485 486 if (done) 487 return; 488 489 /* All fall through to do_early_param. */ 490 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); 491 parse_early_options(tmp_cmdline); 492 done = 1; 493 } 494 495 void __init __weak arch_post_acpi_subsys_init(void) { } 496 497 void __init __weak smp_setup_processor_id(void) 498 { 499 } 500 501 # if THREAD_SIZE >= PAGE_SIZE 502 void __init __weak thread_stack_cache_init(void) 503 { 504 } 505 #endif 506 507 void __init __weak mem_encrypt_init(void) { } 508 509 void __init __weak poking_init(void) { } 510 511 void __init __weak pgtable_cache_init(void) { } 512 513 bool initcall_debug; 514 core_param(initcall_debug, initcall_debug, bool, 0644); 515 516 #ifdef TRACEPOINTS_ENABLED 517 static void __init initcall_debug_enable(void); 518 #else 519 static inline void initcall_debug_enable(void) 520 { 521 } 522 #endif 523 524 /* Report memory auto-initialization states for this boot. */ 525 static void __init report_meminit(void) 526 { 527 const char *stack; 528 529 if (IS_ENABLED(CONFIG_INIT_STACK_ALL)) 530 stack = "all"; 531 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL)) 532 stack = "byref_all"; 533 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF)) 534 stack = "byref"; 535 else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_USER)) 536 stack = "__user"; 537 else 538 stack = "off"; 539 540 pr_info("mem auto-init: stack:%s, heap alloc:%s, heap free:%s\n", 541 stack, want_init_on_alloc(GFP_KERNEL) ? "on" : "off", 542 want_init_on_free() ? "on" : "off"); 543 if (want_init_on_free()) 544 pr_info("mem auto-init: clearing system memory may take some time...\n"); 545 } 546 547 /* 548 * Set up kernel memory allocators 549 */ 550 static void __init mm_init(void) 551 { 552 /* 553 * page_ext requires contiguous pages, 554 * bigger than MAX_ORDER unless SPARSEMEM. 555 */ 556 page_ext_init_flatmem(); 557 report_meminit(); 558 mem_init(); 559 kmem_cache_init(); 560 kmemleak_init(); 561 pgtable_init(); 562 debug_objects_mem_init(); 563 vmalloc_init(); 564 ioremap_huge_init(); 565 /* Should be run before the first non-init thread is created */ 566 init_espfix_bsp(); 567 /* Should be run after espfix64 is set up. */ 568 pti_init(); 569 } 570 571 void __init __weak arch_call_rest_init(void) 572 { 573 rest_init(); 574 } 575 576 asmlinkage __visible void __init start_kernel(void) 577 { 578 char *command_line; 579 char *after_dashes; 580 581 set_task_stack_end_magic(&init_task); 582 smp_setup_processor_id(); 583 debug_objects_early_init(); 584 585 cgroup_init_early(); 586 587 local_irq_disable(); 588 early_boot_irqs_disabled = true; 589 590 /* 591 * Interrupts are still disabled. Do necessary setups, then 592 * enable them. 593 */ 594 boot_cpu_init(); 595 page_address_init(); 596 pr_notice("%s", linux_banner); 597 early_security_init(); 598 setup_arch(&command_line); 599 setup_command_line(command_line); 600 setup_nr_cpu_ids(); 601 setup_per_cpu_areas(); 602 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */ 603 boot_cpu_hotplug_init(); 604 605 build_all_zonelists(NULL); 606 page_alloc_init(); 607 608 pr_notice("Kernel command line: %s\n", boot_command_line); 609 /* parameters may set static keys */ 610 jump_label_init(); 611 parse_early_param(); 612 after_dashes = parse_args("Booting kernel", 613 static_command_line, __start___param, 614 __stop___param - __start___param, 615 -1, -1, NULL, &unknown_bootoption); 616 if (!IS_ERR_OR_NULL(after_dashes)) 617 parse_args("Setting init args", after_dashes, NULL, 0, -1, -1, 618 NULL, set_init_arg); 619 620 /* 621 * These use large bootmem allocations and must precede 622 * kmem_cache_init() 623 */ 624 setup_log_buf(0); 625 vfs_caches_init_early(); 626 sort_main_extable(); 627 trap_init(); 628 mm_init(); 629 630 ftrace_init(); 631 632 /* trace_printk can be enabled here */ 633 early_trace_init(); 634 635 /* 636 * Set up the scheduler prior starting any interrupts (such as the 637 * timer interrupt). Full topology setup happens at smp_init() 638 * time - but meanwhile we still have a functioning scheduler. 639 */ 640 sched_init(); 641 /* 642 * Disable preemption - early bootup scheduling is extremely 643 * fragile until we cpu_idle() for the first time. 644 */ 645 preempt_disable(); 646 if (WARN(!irqs_disabled(), 647 "Interrupts were enabled *very* early, fixing it\n")) 648 local_irq_disable(); 649 radix_tree_init(); 650 651 /* 652 * Set up housekeeping before setting up workqueues to allow the unbound 653 * workqueue to take non-housekeeping into account. 654 */ 655 housekeeping_init(); 656 657 /* 658 * Allow workqueue creation and work item queueing/cancelling 659 * early. Work item execution depends on kthreads and starts after 660 * workqueue_init(). 661 */ 662 workqueue_init_early(); 663 664 rcu_init(); 665 666 /* Trace events are available after this */ 667 trace_init(); 668 669 if (initcall_debug) 670 initcall_debug_enable(); 671 672 context_tracking_init(); 673 /* init some links before init_ISA_irqs() */ 674 early_irq_init(); 675 init_IRQ(); 676 tick_init(); 677 rcu_init_nohz(); 678 init_timers(); 679 hrtimers_init(); 680 softirq_init(); 681 timekeeping_init(); 682 683 /* 684 * For best initial stack canary entropy, prepare it after: 685 * - setup_arch() for any UEFI RNG entropy and boot cmdline access 686 * - timekeeping_init() for ktime entropy used in rand_initialize() 687 * - rand_initialize() to get any arch-specific entropy like RDRAND 688 * - add_latent_entropy() to get any latent entropy 689 * - adding command line entropy 690 */ 691 rand_initialize(); 692 add_latent_entropy(); 693 add_device_randomness(command_line, strlen(command_line)); 694 boot_init_stack_canary(); 695 696 time_init(); 697 printk_safe_init(); 698 perf_event_init(); 699 profile_init(); 700 call_function_init(); 701 WARN(!irqs_disabled(), "Interrupts were enabled early\n"); 702 703 early_boot_irqs_disabled = false; 704 local_irq_enable(); 705 706 kmem_cache_init_late(); 707 708 /* 709 * HACK ALERT! This is early. We're enabling the console before 710 * we've done PCI setups etc, and console_init() must be aware of 711 * this. But we do want output early, in case something goes wrong. 712 */ 713 console_init(); 714 if (panic_later) 715 panic("Too many boot %s vars at `%s'", panic_later, 716 panic_param); 717 718 lockdep_init(); 719 720 /* 721 * Need to run this when irqs are enabled, because it wants 722 * to self-test [hard/soft]-irqs on/off lock inversion bugs 723 * too: 724 */ 725 locking_selftest(); 726 727 /* 728 * This needs to be called before any devices perform DMA 729 * operations that might use the SWIOTLB bounce buffers. It will 730 * mark the bounce buffers as decrypted so that their usage will 731 * not cause "plain-text" data to be decrypted when accessed. 732 */ 733 mem_encrypt_init(); 734 735 #ifdef CONFIG_BLK_DEV_INITRD 736 if (initrd_start && !initrd_below_start_ok && 737 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) { 738 pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n", 739 page_to_pfn(virt_to_page((void *)initrd_start)), 740 min_low_pfn); 741 initrd_start = 0; 742 } 743 #endif 744 setup_per_cpu_pageset(); 745 numa_policy_init(); 746 acpi_early_init(); 747 if (late_time_init) 748 late_time_init(); 749 sched_clock_init(); 750 calibrate_delay(); 751 pid_idr_init(); 752 anon_vma_init(); 753 #ifdef CONFIG_X86 754 if (efi_enabled(EFI_RUNTIME_SERVICES)) 755 efi_enter_virtual_mode(); 756 #endif 757 thread_stack_cache_init(); 758 cred_init(); 759 fork_init(); 760 proc_caches_init(); 761 uts_ns_init(); 762 buffer_init(); 763 key_init(); 764 security_init(); 765 dbg_late_init(); 766 vfs_caches_init(); 767 pagecache_init(); 768 signals_init(); 769 seq_file_init(); 770 proc_root_init(); 771 nsfs_init(); 772 cpuset_init(); 773 cgroup_init(); 774 taskstats_init_early(); 775 delayacct_init(); 776 777 poking_init(); 778 check_bugs(); 779 780 acpi_subsystem_init(); 781 arch_post_acpi_subsys_init(); 782 sfi_init_late(); 783 784 /* Do the rest non-__init'ed, we're now alive */ 785 arch_call_rest_init(); 786 } 787 788 /* Call all constructor functions linked into the kernel. */ 789 static void __init do_ctors(void) 790 { 791 #ifdef CONFIG_CONSTRUCTORS 792 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start; 793 794 for (; fn < (ctor_fn_t *) __ctors_end; fn++) 795 (*fn)(); 796 #endif 797 } 798 799 #ifdef CONFIG_KALLSYMS 800 struct blacklist_entry { 801 struct list_head next; 802 char *buf; 803 }; 804 805 static __initdata_or_module LIST_HEAD(blacklisted_initcalls); 806 807 static int __init initcall_blacklist(char *str) 808 { 809 char *str_entry; 810 struct blacklist_entry *entry; 811 812 /* str argument is a comma-separated list of functions */ 813 do { 814 str_entry = strsep(&str, ","); 815 if (str_entry) { 816 pr_debug("blacklisting initcall %s\n", str_entry); 817 entry = memblock_alloc(sizeof(*entry), 818 SMP_CACHE_BYTES); 819 if (!entry) 820 panic("%s: Failed to allocate %zu bytes\n", 821 __func__, sizeof(*entry)); 822 entry->buf = memblock_alloc(strlen(str_entry) + 1, 823 SMP_CACHE_BYTES); 824 if (!entry->buf) 825 panic("%s: Failed to allocate %zu bytes\n", 826 __func__, strlen(str_entry) + 1); 827 strcpy(entry->buf, str_entry); 828 list_add(&entry->next, &blacklisted_initcalls); 829 } 830 } while (str_entry); 831 832 return 0; 833 } 834 835 static bool __init_or_module initcall_blacklisted(initcall_t fn) 836 { 837 struct blacklist_entry *entry; 838 char fn_name[KSYM_SYMBOL_LEN]; 839 unsigned long addr; 840 841 if (list_empty(&blacklisted_initcalls)) 842 return false; 843 844 addr = (unsigned long) dereference_function_descriptor(fn); 845 sprint_symbol_no_offset(fn_name, addr); 846 847 /* 848 * fn will be "function_name [module_name]" where [module_name] is not 849 * displayed for built-in init functions. Strip off the [module_name]. 850 */ 851 strreplace(fn_name, ' ', '\0'); 852 853 list_for_each_entry(entry, &blacklisted_initcalls, next) { 854 if (!strcmp(fn_name, entry->buf)) { 855 pr_debug("initcall %s blacklisted\n", fn_name); 856 return true; 857 } 858 } 859 860 return false; 861 } 862 #else 863 static int __init initcall_blacklist(char *str) 864 { 865 pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n"); 866 return 0; 867 } 868 869 static bool __init_or_module initcall_blacklisted(initcall_t fn) 870 { 871 return false; 872 } 873 #endif 874 __setup("initcall_blacklist=", initcall_blacklist); 875 876 static __init_or_module void 877 trace_initcall_start_cb(void *data, initcall_t fn) 878 { 879 ktime_t *calltime = (ktime_t *)data; 880 881 printk(KERN_DEBUG "calling %pS @ %i\n", fn, task_pid_nr(current)); 882 *calltime = ktime_get(); 883 } 884 885 static __init_or_module void 886 trace_initcall_finish_cb(void *data, initcall_t fn, int ret) 887 { 888 ktime_t *calltime = (ktime_t *)data; 889 ktime_t delta, rettime; 890 unsigned long long duration; 891 892 rettime = ktime_get(); 893 delta = ktime_sub(rettime, *calltime); 894 duration = (unsigned long long) ktime_to_ns(delta) >> 10; 895 printk(KERN_DEBUG "initcall %pS returned %d after %lld usecs\n", 896 fn, ret, duration); 897 } 898 899 static ktime_t initcall_calltime; 900 901 #ifdef TRACEPOINTS_ENABLED 902 static void __init initcall_debug_enable(void) 903 { 904 int ret; 905 906 ret = register_trace_initcall_start(trace_initcall_start_cb, 907 &initcall_calltime); 908 ret |= register_trace_initcall_finish(trace_initcall_finish_cb, 909 &initcall_calltime); 910 WARN(ret, "Failed to register initcall tracepoints\n"); 911 } 912 # define do_trace_initcall_start trace_initcall_start 913 # define do_trace_initcall_finish trace_initcall_finish 914 #else 915 static inline void do_trace_initcall_start(initcall_t fn) 916 { 917 if (!initcall_debug) 918 return; 919 trace_initcall_start_cb(&initcall_calltime, fn); 920 } 921 static inline void do_trace_initcall_finish(initcall_t fn, int ret) 922 { 923 if (!initcall_debug) 924 return; 925 trace_initcall_finish_cb(&initcall_calltime, fn, ret); 926 } 927 #endif /* !TRACEPOINTS_ENABLED */ 928 929 int __init_or_module do_one_initcall(initcall_t fn) 930 { 931 int count = preempt_count(); 932 char msgbuf[64]; 933 int ret; 934 935 if (initcall_blacklisted(fn)) 936 return -EPERM; 937 938 do_trace_initcall_start(fn); 939 ret = fn(); 940 do_trace_initcall_finish(fn, ret); 941 942 msgbuf[0] = 0; 943 944 if (preempt_count() != count) { 945 sprintf(msgbuf, "preemption imbalance "); 946 preempt_count_set(count); 947 } 948 if (irqs_disabled()) { 949 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf)); 950 local_irq_enable(); 951 } 952 WARN(msgbuf[0], "initcall %pS returned with %s\n", fn, msgbuf); 953 954 add_latent_entropy(); 955 return ret; 956 } 957 958 959 extern initcall_entry_t __initcall_start[]; 960 extern initcall_entry_t __initcall0_start[]; 961 extern initcall_entry_t __initcall1_start[]; 962 extern initcall_entry_t __initcall2_start[]; 963 extern initcall_entry_t __initcall3_start[]; 964 extern initcall_entry_t __initcall4_start[]; 965 extern initcall_entry_t __initcall5_start[]; 966 extern initcall_entry_t __initcall6_start[]; 967 extern initcall_entry_t __initcall7_start[]; 968 extern initcall_entry_t __initcall_end[]; 969 970 static initcall_entry_t *initcall_levels[] __initdata = { 971 __initcall0_start, 972 __initcall1_start, 973 __initcall2_start, 974 __initcall3_start, 975 __initcall4_start, 976 __initcall5_start, 977 __initcall6_start, 978 __initcall7_start, 979 __initcall_end, 980 }; 981 982 /* Keep these in sync with initcalls in include/linux/init.h */ 983 static const char *initcall_level_names[] __initdata = { 984 "pure", 985 "core", 986 "postcore", 987 "arch", 988 "subsys", 989 "fs", 990 "device", 991 "late", 992 }; 993 994 static void __init do_initcall_level(int level) 995 { 996 initcall_entry_t *fn; 997 998 strcpy(initcall_command_line, saved_command_line); 999 parse_args(initcall_level_names[level], 1000 initcall_command_line, __start___param, 1001 __stop___param - __start___param, 1002 level, level, 1003 NULL, &repair_env_string); 1004 1005 trace_initcall_level(initcall_level_names[level]); 1006 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++) 1007 do_one_initcall(initcall_from_entry(fn)); 1008 } 1009 1010 static void __init do_initcalls(void) 1011 { 1012 int level; 1013 1014 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) 1015 do_initcall_level(level); 1016 } 1017 1018 /* 1019 * Ok, the machine is now initialized. None of the devices 1020 * have been touched yet, but the CPU subsystem is up and 1021 * running, and memory and process management works. 1022 * 1023 * Now we can finally start doing some real work.. 1024 */ 1025 static void __init do_basic_setup(void) 1026 { 1027 cpuset_init_smp(); 1028 driver_init(); 1029 init_irq_proc(); 1030 do_ctors(); 1031 usermodehelper_enable(); 1032 do_initcalls(); 1033 } 1034 1035 static void __init do_pre_smp_initcalls(void) 1036 { 1037 initcall_entry_t *fn; 1038 1039 trace_initcall_level("early"); 1040 for (fn = __initcall_start; fn < __initcall0_start; fn++) 1041 do_one_initcall(initcall_from_entry(fn)); 1042 } 1043 1044 static int run_init_process(const char *init_filename) 1045 { 1046 argv_init[0] = init_filename; 1047 pr_info("Run %s as init process\n", init_filename); 1048 return do_execve(getname_kernel(init_filename), 1049 (const char __user *const __user *)argv_init, 1050 (const char __user *const __user *)envp_init); 1051 } 1052 1053 static int try_to_run_init_process(const char *init_filename) 1054 { 1055 int ret; 1056 1057 ret = run_init_process(init_filename); 1058 1059 if (ret && ret != -ENOENT) { 1060 pr_err("Starting init: %s exists but couldn't execute it (error %d)\n", 1061 init_filename, ret); 1062 } 1063 1064 return ret; 1065 } 1066 1067 static noinline void __init kernel_init_freeable(void); 1068 1069 #if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX) 1070 bool rodata_enabled __ro_after_init = true; 1071 static int __init set_debug_rodata(char *str) 1072 { 1073 return strtobool(str, &rodata_enabled); 1074 } 1075 __setup("rodata=", set_debug_rodata); 1076 #endif 1077 1078 #ifdef CONFIG_STRICT_KERNEL_RWX 1079 static void mark_readonly(void) 1080 { 1081 if (rodata_enabled) { 1082 /* 1083 * load_module() results in W+X mappings, which are cleaned 1084 * up with call_rcu(). Let's make sure that queued work is 1085 * flushed so that we don't hit false positives looking for 1086 * insecure pages which are W+X. 1087 */ 1088 rcu_barrier(); 1089 mark_rodata_ro(); 1090 rodata_test(); 1091 } else 1092 pr_info("Kernel memory protection disabled.\n"); 1093 } 1094 #else 1095 static inline void mark_readonly(void) 1096 { 1097 pr_warn("This architecture does not have kernel memory protection.\n"); 1098 } 1099 #endif 1100 1101 void __weak free_initmem(void) 1102 { 1103 free_initmem_default(POISON_FREE_INITMEM); 1104 } 1105 1106 static int __ref kernel_init(void *unused) 1107 { 1108 int ret; 1109 1110 kernel_init_freeable(); 1111 /* need to finish all async __init code before freeing the memory */ 1112 async_synchronize_full(); 1113 ftrace_free_init_mem(); 1114 free_initmem(); 1115 mark_readonly(); 1116 1117 /* 1118 * Kernel mappings are now finalized - update the userspace page-table 1119 * to finalize PTI. 1120 */ 1121 pti_finalize(); 1122 1123 system_state = SYSTEM_RUNNING; 1124 numa_default_policy(); 1125 1126 rcu_end_inkernel_boot(); 1127 1128 if (ramdisk_execute_command) { 1129 ret = run_init_process(ramdisk_execute_command); 1130 if (!ret) 1131 return 0; 1132 pr_err("Failed to execute %s (error %d)\n", 1133 ramdisk_execute_command, ret); 1134 } 1135 1136 /* 1137 * We try each of these until one succeeds. 1138 * 1139 * The Bourne shell can be used instead of init if we are 1140 * trying to recover a really broken machine. 1141 */ 1142 if (execute_command) { 1143 ret = run_init_process(execute_command); 1144 if (!ret) 1145 return 0; 1146 panic("Requested init %s failed (error %d).", 1147 execute_command, ret); 1148 } 1149 if (!try_to_run_init_process("/sbin/init") || 1150 !try_to_run_init_process("/etc/init") || 1151 !try_to_run_init_process("/bin/init") || 1152 !try_to_run_init_process("/bin/sh")) 1153 return 0; 1154 1155 panic("No working init found. Try passing init= option to kernel. " 1156 "See Linux Documentation/admin-guide/init.rst for guidance."); 1157 } 1158 1159 void console_on_rootfs(void) 1160 { 1161 struct file *file; 1162 unsigned int i; 1163 1164 /* Open /dev/console in kernelspace, this should never fail */ 1165 file = filp_open("/dev/console", O_RDWR, 0); 1166 if (!file) 1167 goto err_out; 1168 1169 /* create stdin/stdout/stderr, this should never fail */ 1170 for (i = 0; i < 3; i++) { 1171 if (f_dupfd(i, file, 0) != i) 1172 goto err_out; 1173 } 1174 1175 return; 1176 1177 err_out: 1178 /* no panic -- this might not be fatal */ 1179 pr_err("Warning: unable to open an initial console.\n"); 1180 return; 1181 } 1182 1183 static noinline void __init kernel_init_freeable(void) 1184 { 1185 /* 1186 * Wait until kthreadd is all set-up. 1187 */ 1188 wait_for_completion(&kthreadd_done); 1189 1190 /* Now the scheduler is fully set up and can do blocking allocations */ 1191 gfp_allowed_mask = __GFP_BITS_MASK; 1192 1193 /* 1194 * init can allocate pages on any node 1195 */ 1196 set_mems_allowed(node_states[N_MEMORY]); 1197 1198 cad_pid = task_pid(current); 1199 1200 smp_prepare_cpus(setup_max_cpus); 1201 1202 workqueue_init(); 1203 1204 init_mm_internals(); 1205 1206 do_pre_smp_initcalls(); 1207 lockup_detector_init(); 1208 1209 smp_init(); 1210 sched_init_smp(); 1211 1212 page_alloc_init_late(); 1213 /* Initialize page ext after all struct pages are initialized. */ 1214 page_ext_init(); 1215 1216 do_basic_setup(); 1217 1218 console_on_rootfs(); 1219 1220 /* 1221 * check if there is an early userspace init. If yes, let it do all 1222 * the work 1223 */ 1224 1225 if (!ramdisk_execute_command) 1226 ramdisk_execute_command = "/init"; 1227 1228 if (ksys_access((const char __user *) 1229 ramdisk_execute_command, 0) != 0) { 1230 ramdisk_execute_command = NULL; 1231 prepare_namespace(); 1232 } 1233 1234 /* 1235 * Ok, we have completed the initial bootup, and 1236 * we're essentially up and running. Get rid of the 1237 * initmem segments and start the user-mode stuff.. 1238 * 1239 * rootfs is available now, try loading the public keys 1240 * and default modules 1241 */ 1242 1243 integrity_load_keys(); 1244 } 1245