Line data Source code
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/moduleparam.h>
46 : #include <linux/kallsyms.h>
47 : #include <linux/writeback.h>
48 : #include <linux/cpu.h>
49 : #include <linux/cpuset.h>
50 : #include <linux/cgroup.h>
51 : #include <linux/efi.h>
52 : #include <linux/tick.h>
53 : #include <linux/sched/isolation.h>
54 : #include <linux/interrupt.h>
55 : #include <linux/taskstats_kern.h>
56 : #include <linux/delayacct.h>
57 : #include <linux/unistd.h>
58 : #include <linux/utsname.h>
59 : #include <linux/rmap.h>
60 : #include <linux/mempolicy.h>
61 : #include <linux/key.h>
62 : #include <linux/page_ext.h>
63 : #include <linux/debug_locks.h>
64 : #include <linux/debugobjects.h>
65 : #include <linux/lockdep.h>
66 : #include <linux/kmemleak.h>
67 : #include <linux/padata.h>
68 : #include <linux/pid_namespace.h>
69 : #include <linux/device/driver.h>
70 : #include <linux/kthread.h>
71 : #include <linux/sched.h>
72 : #include <linux/sched/init.h>
73 : #include <linux/signal.h>
74 : #include <linux/idr.h>
75 : #include <linux/kgdb.h>
76 : #include <linux/ftrace.h>
77 : #include <linux/async.h>
78 : #include <linux/shmem_fs.h>
79 : #include <linux/slab.h>
80 : #include <linux/perf_event.h>
81 : #include <linux/ptrace.h>
82 : #include <linux/pti.h>
83 : #include <linux/blkdev.h>
84 : #include <linux/elevator.h>
85 : #include <linux/sched/clock.h>
86 : #include <linux/sched/task.h>
87 : #include <linux/sched/task_stack.h>
88 : #include <linux/context_tracking.h>
89 : #include <linux/random.h>
90 : #include <linux/list.h>
91 : #include <linux/integrity.h>
92 : #include <linux/proc_ns.h>
93 : #include <linux/io.h>
94 : #include <linux/cache.h>
95 : #include <linux/rodata_test.h>
96 : #include <linux/jump_label.h>
97 : #include <linux/mem_encrypt.h>
98 : #include <linux/kcsan.h>
99 : #include <linux/init_syscalls.h>
100 : #include <linux/stackdepot.h>
101 :
102 : #include <asm/io.h>
103 : #include <asm/bugs.h>
104 : #include <asm/setup.h>
105 : #include <asm/sections.h>
106 : #include <asm/cacheflush.h>
107 :
108 : #define CREATE_TRACE_POINTS
109 : #include <trace/events/initcall.h>
110 :
111 : #include <kunit/test.h>
112 :
113 : static int kernel_init(void *);
114 :
115 : extern void init_IRQ(void);
116 : extern void radix_tree_init(void);
117 :
118 : /*
119 : * Debug helper: via this flag we know that we are in 'early bootup code'
120 : * where only the boot processor is running with IRQ disabled. This means
121 : * two things - IRQ must not be enabled before the flag is cleared and some
122 : * operations which are not allowed with IRQ disabled are allowed while the
123 : * flag is set.
124 : */
125 : bool early_boot_irqs_disabled __read_mostly;
126 :
127 : enum system_states system_state __read_mostly;
128 : EXPORT_SYMBOL(system_state);
129 :
130 : /*
131 : * Boot command-line arguments
132 : */
133 : #define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
134 : #define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
135 :
136 : extern void time_init(void);
137 : /* Default late time init is NULL. archs can override this later. */
138 : void (*__initdata late_time_init)(void);
139 :
140 : /* Untouched command line saved by arch-specific code. */
141 : char __initdata boot_command_line[COMMAND_LINE_SIZE];
142 : /* Untouched saved command line (eg. for /proc) */
143 : char *saved_command_line;
144 : /* Command line for parameter parsing */
145 : static char *static_command_line;
146 : /* Untouched extra command line */
147 : static char *extra_command_line;
148 : /* Extra init arguments */
149 : static char *extra_init_args;
150 :
151 : #ifdef CONFIG_BOOT_CONFIG
152 : /* Is bootconfig on command line? */
153 : static bool bootconfig_found;
154 : static bool initargs_found;
155 : #else
156 : # define bootconfig_found false
157 : # define initargs_found false
158 : #endif
159 :
160 : static char *execute_command;
161 : static char *ramdisk_execute_command = "/init";
162 :
163 : /*
164 : * Used to generate warnings if static_key manipulation functions are used
165 : * before jump_label_init is called.
166 : */
167 : bool static_key_initialized __read_mostly;
168 : EXPORT_SYMBOL_GPL(static_key_initialized);
169 :
170 : /*
171 : * If set, this is an indication to the drivers that reset the underlying
172 : * device before going ahead with the initialization otherwise driver might
173 : * rely on the BIOS and skip the reset operation.
174 : *
175 : * This is useful if kernel is booting in an unreliable environment.
176 : * For ex. kdump situation where previous kernel has crashed, BIOS has been
177 : * skipped and devices will be in unknown state.
178 : */
179 : unsigned int reset_devices;
180 : EXPORT_SYMBOL(reset_devices);
181 :
182 0 : static int __init set_reset_devices(char *str)
183 : {
184 0 : reset_devices = 1;
185 0 : return 1;
186 : }
187 :
188 : __setup("reset_devices", set_reset_devices);
189 :
190 : static const char *argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
191 : const char *envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
192 : static const char *panic_later, *panic_param;
193 :
194 : extern const struct obs_kernel_param __setup_start[], __setup_end[];
195 :
196 4 : static bool __init obsolete_checksetup(char *line)
197 : {
198 4 : const struct obs_kernel_param *p;
199 4 : bool had_early_param = false;
200 :
201 4 : p = __setup_start;
202 242 : do {
203 242 : int n = strlen(p->str);
204 242 : if (parameqn(line, p->str, n)) {
205 4 : if (p->early) {
206 : /* Already done in parse_early_param?
207 : * (Needs exact match on param part).
208 : * Keep iterating, as we can have early
209 : * params and __setups of same names 8( */
210 0 : if (line[n] == '\0' || line[n] == '=')
211 0 : had_early_param = true;
212 4 : } else if (!p->setup_func) {
213 0 : pr_warn("Parameter %s is obsolete, ignored\n",
214 : p->str);
215 0 : return true;
216 4 : } else if (p->setup_func(line + n))
217 : return true;
218 : }
219 238 : p++;
220 238 : } while (p < __setup_end);
221 :
222 : return had_early_param;
223 : }
224 :
225 : /*
226 : * This should be approx 2 Bo*oMips to start (note initial shift), and will
227 : * still work even if initially too large, it will just take slightly longer
228 : */
229 : unsigned long loops_per_jiffy = (1<<12);
230 : EXPORT_SYMBOL(loops_per_jiffy);
231 :
232 0 : static int __init debug_kernel(char *str)
233 : {
234 0 : console_loglevel = CONSOLE_LOGLEVEL_DEBUG;
235 0 : return 0;
236 : }
237 :
238 0 : static int __init quiet_kernel(char *str)
239 : {
240 0 : console_loglevel = CONSOLE_LOGLEVEL_QUIET;
241 0 : return 0;
242 : }
243 :
244 : early_param("debug", debug_kernel);
245 : early_param("quiet", quiet_kernel);
246 :
247 0 : static int __init loglevel(char *str)
248 : {
249 0 : int newlevel;
250 :
251 : /*
252 : * Only update loglevel value when a correct setting was passed,
253 : * to prevent blind crashes (when loglevel being set to 0) that
254 : * are quite hard to debug
255 : */
256 0 : if (get_option(&str, &newlevel)) {
257 0 : console_loglevel = newlevel;
258 0 : return 0;
259 : }
260 :
261 : return -EINVAL;
262 : }
263 :
264 : early_param("loglevel", loglevel);
265 :
266 : #ifdef CONFIG_BLK_DEV_INITRD
267 1 : static void * __init get_boot_config_from_initrd(u32 *_size, u32 *_csum)
268 : {
269 1 : u32 size, csum;
270 1 : char *data;
271 1 : u32 *hdr;
272 1 : int i;
273 :
274 1 : if (!initrd_end)
275 : return NULL;
276 :
277 0 : data = (char *)initrd_end - BOOTCONFIG_MAGIC_LEN;
278 : /*
279 : * Since Grub may align the size of initrd to 4, we must
280 : * check the preceding 3 bytes as well.
281 : */
282 0 : for (i = 0; i < 4; i++) {
283 0 : if (!memcmp(data, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN))
284 0 : goto found;
285 0 : data--;
286 : }
287 : return NULL;
288 :
289 0 : found:
290 0 : hdr = (u32 *)(data - 8);
291 0 : size = le32_to_cpu(hdr[0]);
292 0 : csum = le32_to_cpu(hdr[1]);
293 :
294 0 : data = ((void *)hdr) - size;
295 0 : if ((unsigned long)data < initrd_start) {
296 0 : pr_err("bootconfig size %d is greater than initrd size %ld\n",
297 : size, initrd_end - initrd_start);
298 0 : return NULL;
299 : }
300 :
301 : /* Remove bootconfig from initramfs/initrd */
302 0 : initrd_end = (unsigned long)data;
303 0 : if (_size)
304 0 : *_size = size;
305 0 : if (_csum)
306 0 : *_csum = csum;
307 :
308 : return data;
309 : }
310 : #else
311 : static void * __init get_boot_config_from_initrd(u32 *_size, u32 *_csum)
312 : {
313 : return NULL;
314 : }
315 : #endif
316 :
317 : #ifdef CONFIG_BOOT_CONFIG
318 :
319 : static char xbc_namebuf[XBC_KEYLEN_MAX] __initdata;
320 :
321 : #define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0)
322 :
323 : static int __init xbc_snprint_cmdline(char *buf, size_t size,
324 : struct xbc_node *root)
325 : {
326 : struct xbc_node *knode, *vnode;
327 : char *end = buf + size;
328 : const char *val;
329 : int ret;
330 :
331 : xbc_node_for_each_key_value(root, knode, val) {
332 : ret = xbc_node_compose_key_after(root, knode,
333 : xbc_namebuf, XBC_KEYLEN_MAX);
334 : if (ret < 0)
335 : return ret;
336 :
337 : vnode = xbc_node_get_child(knode);
338 : if (!vnode) {
339 : ret = snprintf(buf, rest(buf, end), "%s ", xbc_namebuf);
340 : if (ret < 0)
341 : return ret;
342 : buf += ret;
343 : continue;
344 : }
345 : xbc_array_for_each_value(vnode, val) {
346 : ret = snprintf(buf, rest(buf, end), "%s=\"%s\" ",
347 : xbc_namebuf, val);
348 : if (ret < 0)
349 : return ret;
350 : buf += ret;
351 : }
352 : }
353 :
354 : return buf - (end - size);
355 : }
356 : #undef rest
357 :
358 : /* Make an extra command line under given key word */
359 : static char * __init xbc_make_cmdline(const char *key)
360 : {
361 : struct xbc_node *root;
362 : char *new_cmdline;
363 : int ret, len = 0;
364 :
365 : root = xbc_find_node(key);
366 : if (!root)
367 : return NULL;
368 :
369 : /* Count required buffer size */
370 : len = xbc_snprint_cmdline(NULL, 0, root);
371 : if (len <= 0)
372 : return NULL;
373 :
374 : new_cmdline = memblock_alloc(len + 1, SMP_CACHE_BYTES);
375 : if (!new_cmdline) {
376 : pr_err("Failed to allocate memory for extra kernel cmdline.\n");
377 : return NULL;
378 : }
379 :
380 : ret = xbc_snprint_cmdline(new_cmdline, len + 1, root);
381 : if (ret < 0 || ret > len) {
382 : pr_err("Failed to print extra kernel cmdline.\n");
383 : return NULL;
384 : }
385 :
386 : return new_cmdline;
387 : }
388 :
389 : static u32 boot_config_checksum(unsigned char *p, u32 size)
390 : {
391 : u32 ret = 0;
392 :
393 : while (size--)
394 : ret += *p++;
395 :
396 : return ret;
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 void __init setup_boot_config(const char *cmdline)
409 : {
410 : static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata;
411 : const char *msg;
412 : int pos;
413 : u32 size, csum;
414 : char *data, *copy, *err;
415 : int ret;
416 :
417 : /* Cut out the bootconfig data even if we have no bootconfig option */
418 : data = get_boot_config_from_initrd(&size, &csum);
419 :
420 : strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
421 : err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL,
422 : bootconfig_params);
423 :
424 : if (IS_ERR(err) || !bootconfig_found)
425 : return;
426 :
427 : /* parse_args() stops at '--' and returns an address */
428 : if (err)
429 : initargs_found = true;
430 :
431 : if (!data) {
432 : pr_err("'bootconfig' found on command line, but no bootconfig found\n");
433 : return;
434 : }
435 :
436 : if (size >= XBC_DATA_MAX) {
437 : pr_err("bootconfig size %d greater than max size %d\n",
438 : size, XBC_DATA_MAX);
439 : return;
440 : }
441 :
442 : if (boot_config_checksum((unsigned char *)data, size) != csum) {
443 : pr_err("bootconfig checksum failed\n");
444 : return;
445 : }
446 :
447 : copy = memblock_alloc(size + 1, SMP_CACHE_BYTES);
448 : if (!copy) {
449 : pr_err("Failed to allocate memory for bootconfig\n");
450 : return;
451 : }
452 :
453 : memcpy(copy, data, size);
454 : copy[size] = '\0';
455 :
456 : ret = xbc_init(copy, &msg, &pos);
457 : if (ret < 0) {
458 : if (pos < 0)
459 : pr_err("Failed to init bootconfig: %s.\n", msg);
460 : else
461 : pr_err("Failed to parse bootconfig: %s at %d.\n",
462 : msg, pos);
463 : } else {
464 : pr_info("Load bootconfig: %d bytes %d nodes\n", size, ret);
465 : /* keys starting with "kernel." are passed via cmdline */
466 : extra_command_line = xbc_make_cmdline("kernel");
467 : /* Also, "init." keys are init arguments */
468 : extra_init_args = xbc_make_cmdline("init");
469 : }
470 : return;
471 : }
472 :
473 : #else
474 :
475 1 : static void __init setup_boot_config(const char *cmdline)
476 : {
477 : /* Remove bootconfig data from initrd */
478 1 : get_boot_config_from_initrd(NULL, NULL);
479 1 : }
480 :
481 0 : static int __init warn_bootconfig(char *str)
482 : {
483 0 : pr_warn("WARNING: 'bootconfig' found on the kernel command line but CONFIG_BOOT_CONFIG is not set.\n");
484 0 : return 0;
485 : }
486 : early_param("bootconfig", warn_bootconfig);
487 :
488 : #endif
489 :
490 : /* Change NUL term back to "=", to make "param" the whole string. */
491 4 : static void __init repair_env_string(char *param, char *val)
492 : {
493 4 : if (val) {
494 : /* param=val or param="val"? */
495 3 : if (val == param+strlen(param)+1)
496 3 : val[-1] = '=';
497 0 : else if (val == param+strlen(param)+2) {
498 0 : val[-2] = '=';
499 0 : memmove(val-1, val, strlen(val)+1);
500 : } else
501 0 : BUG();
502 : }
503 4 : }
504 :
505 : /* Anything after -- gets handed straight to init. */
506 0 : static int __init set_init_arg(char *param, char *val,
507 : const char *unused, void *arg)
508 : {
509 0 : unsigned int i;
510 :
511 0 : if (panic_later)
512 : return 0;
513 :
514 0 : repair_env_string(param, val);
515 :
516 0 : for (i = 0; argv_init[i]; i++) {
517 0 : if (i == MAX_INIT_ARGS) {
518 0 : panic_later = "init";
519 0 : panic_param = param;
520 0 : return 0;
521 : }
522 : }
523 0 : argv_init[i] = param;
524 0 : return 0;
525 : }
526 :
527 : /*
528 : * Unknown boot options get handed to init, unless they look like
529 : * unused parameters (modprobe will find them in /proc/cmdline).
530 : */
531 4 : static int __init unknown_bootoption(char *param, char *val,
532 : const char *unused, void *arg)
533 : {
534 4 : size_t len = strlen(param);
535 :
536 4 : repair_env_string(param, val);
537 :
538 : /* Handle obsolete-style parameters */
539 4 : if (obsolete_checksetup(param))
540 : return 0;
541 :
542 : /* Unused module parameter. */
543 0 : if (strnchr(param, len, '.'))
544 : return 0;
545 :
546 0 : if (panic_later)
547 : return 0;
548 :
549 0 : if (val) {
550 : /* Environment option */
551 : unsigned int i;
552 0 : for (i = 0; envp_init[i]; i++) {
553 0 : if (i == MAX_INIT_ENVS) {
554 0 : panic_later = "env";
555 0 : panic_param = param;
556 : }
557 0 : if (!strncmp(param, envp_init[i], len+1))
558 : break;
559 : }
560 0 : envp_init[i] = param;
561 : } else {
562 : /* Command line option */
563 : unsigned int i;
564 0 : for (i = 0; argv_init[i]; i++) {
565 0 : if (i == MAX_INIT_ARGS) {
566 0 : panic_later = "init";
567 0 : panic_param = param;
568 : }
569 : }
570 0 : argv_init[i] = param;
571 : }
572 : return 0;
573 : }
574 :
575 0 : static int __init init_setup(char *str)
576 : {
577 0 : unsigned int i;
578 :
579 0 : execute_command = str;
580 : /*
581 : * In case LILO is going to boot us with default command line,
582 : * it prepends "auto" before the whole cmdline which makes
583 : * the shell think it should execute a script with such name.
584 : * So we ignore all arguments entered _before_ init=... [MJ]
585 : */
586 0 : for (i = 1; i < MAX_INIT_ARGS; i++)
587 0 : argv_init[i] = NULL;
588 0 : return 1;
589 : }
590 : __setup("init=", init_setup);
591 :
592 0 : static int __init rdinit_setup(char *str)
593 : {
594 0 : unsigned int i;
595 :
596 0 : ramdisk_execute_command = str;
597 : /* See "auto" comment in init_setup */
598 0 : for (i = 1; i < MAX_INIT_ARGS; i++)
599 0 : argv_init[i] = NULL;
600 0 : return 1;
601 : }
602 : __setup("rdinit=", rdinit_setup);
603 :
604 : #ifndef CONFIG_SMP
605 : static const unsigned int setup_max_cpus = NR_CPUS;
606 : static inline void setup_nr_cpu_ids(void) { }
607 : static inline void smp_prepare_cpus(unsigned int maxcpus) { }
608 : #endif
609 :
610 : /*
611 : * We need to store the untouched command line for future reference.
612 : * We also need to store the touched command line since the parameter
613 : * parsing is performed in place, and we should allow a component to
614 : * store reference of name/value for future reference.
615 : */
616 1 : static void __init setup_command_line(char *command_line)
617 : {
618 1 : size_t len, xlen = 0, ilen = 0;
619 :
620 1 : if (extra_command_line)
621 0 : xlen = strlen(extra_command_line);
622 1 : if (extra_init_args)
623 0 : ilen = strlen(extra_init_args) + 4; /* for " -- " */
624 :
625 1 : len = xlen + strlen(boot_command_line) + 1;
626 :
627 1 : saved_command_line = memblock_alloc(len + ilen, SMP_CACHE_BYTES);
628 1 : if (!saved_command_line)
629 0 : panic("%s: Failed to allocate %zu bytes\n", __func__, len + ilen);
630 :
631 1 : static_command_line = memblock_alloc(len, SMP_CACHE_BYTES);
632 1 : if (!static_command_line)
633 0 : panic("%s: Failed to allocate %zu bytes\n", __func__, len);
634 :
635 1 : if (xlen) {
636 : /*
637 : * We have to put extra_command_line before boot command
638 : * lines because there could be dashes (separator of init
639 : * command line) in the command lines.
640 : */
641 0 : strcpy(saved_command_line, extra_command_line);
642 0 : strcpy(static_command_line, extra_command_line);
643 : }
644 1 : strcpy(saved_command_line + xlen, boot_command_line);
645 1 : strcpy(static_command_line + xlen, command_line);
646 :
647 1 : if (ilen) {
648 : /*
649 : * Append supplemental init boot args to saved_command_line
650 : * so that user can check what command line options passed
651 : * to init.
652 : */
653 0 : len = strlen(saved_command_line);
654 0 : if (initargs_found) {
655 : saved_command_line[len++] = ' ';
656 : } else {
657 0 : strcpy(saved_command_line + len, " -- ");
658 0 : len += 4;
659 : }
660 :
661 0 : strcpy(saved_command_line + len, extra_init_args);
662 : }
663 1 : }
664 :
665 : /*
666 : * We need to finalize in a non-__init function or else race conditions
667 : * between the root thread and the init thread may cause start_kernel to
668 : * be reaped by free_initmem before the root thread has proceeded to
669 : * cpu_idle.
670 : *
671 : * gcc-3.4 accidentally inlines this function, so use noinline.
672 : */
673 :
674 : static __initdata DECLARE_COMPLETION(kthreadd_done);
675 :
676 1 : noinline void __ref rest_init(void)
677 : {
678 1 : struct task_struct *tsk;
679 1 : int pid;
680 :
681 1 : rcu_scheduler_starting();
682 : /*
683 : * We need to spawn init first so that it obtains pid 1, however
684 : * the init task will end up wanting to create kthreads, which, if
685 : * we schedule it before we create kthreadd, will OOPS.
686 : */
687 1 : pid = kernel_thread(kernel_init, NULL, CLONE_FS);
688 : /*
689 : * Pin init on the boot CPU. Task migration is not properly working
690 : * until sched_init_smp() has been run. It will set the allowed
691 : * CPUs for init to the non isolated CPUs.
692 : */
693 1 : rcu_read_lock();
694 1 : tsk = find_task_by_pid_ns(pid, &init_pid_ns);
695 1 : set_cpus_allowed_ptr(tsk, cpumask_of(smp_processor_id()));
696 1 : rcu_read_unlock();
697 :
698 1 : numa_default_policy();
699 1 : pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
700 1 : rcu_read_lock();
701 1 : kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
702 1 : rcu_read_unlock();
703 :
704 : /*
705 : * Enable might_sleep() and smp_processor_id() checks.
706 : * They cannot be enabled earlier because with CONFIG_PREEMPTION=y
707 : * kernel_thread() would trigger might_sleep() splats. With
708 : * CONFIG_PREEMPT_VOLUNTARY=y the init task might have scheduled
709 : * already, but it's stuck on the kthreadd_done completion.
710 : */
711 1 : system_state = SYSTEM_SCHEDULING;
712 :
713 1 : complete(&kthreadd_done);
714 :
715 : /*
716 : * The boot idle thread must execute schedule()
717 : * at least once to get things moving:
718 : */
719 1 : schedule_preempt_disabled();
720 : /* Call into cpu_idle with preempt disabled */
721 1 : cpu_startup_entry(CPUHP_ONLINE);
722 0 : }
723 :
724 : /* Check for early params. */
725 6 : static int __init do_early_param(char *param, char *val,
726 : const char *unused, void *arg)
727 : {
728 6 : const struct obs_kernel_param *p;
729 :
730 1158 : for (p = __setup_start; p < __setup_end; p++) {
731 1152 : if ((p->early && parameq(param, p->str)) ||
732 1152 : (strcmp(param, "console") == 0 &&
733 192 : strcmp(p->str, "earlycon") == 0)
734 : ) {
735 1 : if (p->setup_func(val) != 0)
736 0 : pr_warn("Malformed early option '%s'\n", param);
737 : }
738 : }
739 : /* We accept everything at this stage. */
740 6 : return 0;
741 : }
742 :
743 1 : void __init parse_early_options(char *cmdline)
744 : {
745 1 : parse_args("early options", cmdline, NULL, 0, 0, 0, NULL,
746 : do_early_param);
747 1 : }
748 :
749 : /* Arch code calls this early on, or if not, just before other parsing. */
750 2 : void __init parse_early_param(void)
751 : {
752 2 : static int done __initdata;
753 2 : static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata;
754 :
755 2 : if (done)
756 : return;
757 :
758 : /* All fall through to do_early_param. */
759 1 : strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
760 1 : parse_early_options(tmp_cmdline);
761 1 : done = 1;
762 : }
763 :
764 0 : void __init __weak arch_post_acpi_subsys_init(void) { }
765 :
766 1 : void __init __weak smp_setup_processor_id(void)
767 : {
768 1 : }
769 :
770 : # if THREAD_SIZE >= PAGE_SIZE
771 1 : void __init __weak thread_stack_cache_init(void)
772 : {
773 1 : }
774 : #endif
775 :
776 1 : void __init __weak mem_encrypt_init(void) { }
777 :
778 0 : void __init __weak poking_init(void) { }
779 :
780 1 : void __init __weak pgtable_cache_init(void) { }
781 :
782 : bool initcall_debug;
783 : core_param(initcall_debug, initcall_debug, bool, 0644);
784 :
785 : #ifdef TRACEPOINTS_ENABLED
786 : static void __init initcall_debug_enable(void);
787 : #else
788 : static inline void initcall_debug_enable(void)
789 : {
790 : }
791 : #endif
792 :
793 : /* Report memory auto-initialization states for this boot. */
794 1 : static void __init report_meminit(void)
795 : {
796 1 : const char *stack;
797 :
798 1 : if (IS_ENABLED(CONFIG_INIT_STACK_ALL_PATTERN))
799 : stack = "all(pattern)";
800 1 : else if (IS_ENABLED(CONFIG_INIT_STACK_ALL_ZERO))
801 : stack = "all(zero)";
802 1 : else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL))
803 : stack = "byref_all(zero)";
804 1 : else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF))
805 : stack = "byref(zero)";
806 1 : else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_USER))
807 : stack = "__user(zero)";
808 : else
809 1 : stack = "off";
810 :
811 2 : pr_info("mem auto-init: stack:%s, heap alloc:%s, heap free:%s\n",
812 : stack, want_init_on_alloc(GFP_KERNEL) ? "on" : "off",
813 : want_init_on_free() ? "on" : "off");
814 1 : if (want_init_on_free())
815 0 : pr_info("mem auto-init: clearing system memory may take some time...\n");
816 1 : }
817 :
818 : /*
819 : * Set up kernel memory allocators
820 : */
821 1 : static void __init mm_init(void)
822 : {
823 : /*
824 : * page_ext requires contiguous pages,
825 : * bigger than MAX_ORDER unless SPARSEMEM.
826 : */
827 1 : page_ext_init_flatmem();
828 1 : init_mem_debugging_and_hardening();
829 1 : kfence_alloc_pool();
830 1 : report_meminit();
831 1 : stack_depot_init();
832 1 : mem_init();
833 : /* page_owner must be initialized after buddy is ready */
834 1 : page_ext_init_flatmem_late();
835 1 : kmem_cache_init();
836 1 : kmemleak_init();
837 1 : pgtable_init();
838 1 : debug_objects_mem_init();
839 1 : vmalloc_init();
840 1 : ioremap_huge_init();
841 : /* Should be run before the first non-init thread is created */
842 1 : init_espfix_bsp();
843 : /* Should be run after espfix64 is set up. */
844 1 : pti_init();
845 1 : }
846 :
847 1 : void __init __weak arch_call_rest_init(void)
848 : {
849 1 : rest_init();
850 0 : }
851 :
852 1 : asmlinkage __visible void __init __no_sanitize_address start_kernel(void)
853 : {
854 1 : char *command_line;
855 1 : char *after_dashes;
856 :
857 1 : set_task_stack_end_magic(&init_task);
858 1 : smp_setup_processor_id();
859 1 : debug_objects_early_init();
860 :
861 1 : cgroup_init_early();
862 :
863 1 : local_irq_disable();
864 1 : early_boot_irqs_disabled = true;
865 :
866 : /*
867 : * Interrupts are still disabled. Do necessary setups, then
868 : * enable them.
869 : */
870 1 : boot_cpu_init();
871 1 : page_address_init();
872 1 : pr_notice("%s", linux_banner);
873 1 : early_security_init();
874 1 : setup_arch(&command_line);
875 1 : setup_boot_config(command_line);
876 1 : setup_command_line(command_line);
877 1 : setup_nr_cpu_ids();
878 1 : setup_per_cpu_areas();
879 1 : smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
880 1 : boot_cpu_hotplug_init();
881 :
882 1 : build_all_zonelists(NULL);
883 1 : page_alloc_init();
884 :
885 1 : pr_notice("Kernel command line: %s\n", saved_command_line);
886 : /* parameters may set static keys */
887 1 : jump_label_init();
888 1 : parse_early_param();
889 2 : after_dashes = parse_args("Booting kernel",
890 : static_command_line, __start___param,
891 1 : __stop___param - __start___param,
892 : -1, -1, NULL, &unknown_bootoption);
893 1 : if (!IS_ERR_OR_NULL(after_dashes))
894 0 : parse_args("Setting init args", after_dashes, NULL, 0, -1, -1,
895 : NULL, set_init_arg);
896 1 : if (extra_init_args)
897 0 : parse_args("Setting extra init args", extra_init_args,
898 : NULL, 0, -1, -1, NULL, set_init_arg);
899 :
900 : /*
901 : * These use large bootmem allocations and must precede
902 : * kmem_cache_init()
903 : */
904 1 : setup_log_buf(0);
905 1 : vfs_caches_init_early();
906 1 : sort_main_extable();
907 1 : trap_init();
908 1 : mm_init();
909 :
910 1 : ftrace_init();
911 :
912 : /* trace_printk can be enabled here */
913 1 : early_trace_init();
914 :
915 : /*
916 : * Set up the scheduler prior starting any interrupts (such as the
917 : * timer interrupt). Full topology setup happens at smp_init()
918 : * time - but meanwhile we still have a functioning scheduler.
919 : */
920 1 : sched_init();
921 : /*
922 : * Disable preemption - early bootup scheduling is extremely
923 : * fragile until we cpu_idle() for the first time.
924 : */
925 1 : preempt_disable();
926 1 : if (WARN(!irqs_disabled(),
927 : "Interrupts were enabled *very* early, fixing it\n"))
928 0 : local_irq_disable();
929 1 : radix_tree_init();
930 :
931 : /*
932 : * Set up housekeeping before setting up workqueues to allow the unbound
933 : * workqueue to take non-housekeeping into account.
934 : */
935 1 : housekeeping_init();
936 :
937 : /*
938 : * Allow workqueue creation and work item queueing/cancelling
939 : * early. Work item execution depends on kthreads and starts after
940 : * workqueue_init().
941 : */
942 1 : workqueue_init_early();
943 :
944 1 : rcu_init();
945 :
946 : /* Trace events are available after this */
947 1 : trace_init();
948 :
949 1 : if (initcall_debug)
950 0 : initcall_debug_enable();
951 :
952 1 : context_tracking_init();
953 : /* init some links before init_ISA_irqs() */
954 1 : early_irq_init();
955 1 : init_IRQ();
956 1 : tick_init();
957 1 : rcu_init_nohz();
958 1 : init_timers();
959 1 : hrtimers_init();
960 1 : softirq_init();
961 1 : timekeeping_init();
962 1 : kfence_init();
963 :
964 : /*
965 : * For best initial stack canary entropy, prepare it after:
966 : * - setup_arch() for any UEFI RNG entropy and boot cmdline access
967 : * - timekeeping_init() for ktime entropy used in rand_initialize()
968 : * - rand_initialize() to get any arch-specific entropy like RDRAND
969 : * - add_latent_entropy() to get any latent entropy
970 : * - adding command line entropy
971 : */
972 1 : rand_initialize();
973 1 : add_latent_entropy();
974 1 : add_device_randomness(command_line, strlen(command_line));
975 1 : boot_init_stack_canary();
976 :
977 1 : time_init();
978 1 : perf_event_init();
979 1 : profile_init();
980 1 : call_function_init();
981 1 : WARN(!irqs_disabled(), "Interrupts were enabled early\n");
982 :
983 1 : early_boot_irqs_disabled = false;
984 1 : local_irq_enable();
985 :
986 1 : kmem_cache_init_late();
987 :
988 : /*
989 : * HACK ALERT! This is early. We're enabling the console before
990 : * we've done PCI setups etc, and console_init() must be aware of
991 : * this. But we do want output early, in case something goes wrong.
992 : */
993 1 : console_init();
994 1 : if (panic_later)
995 0 : panic("Too many boot %s vars at `%s'", panic_later,
996 : panic_param);
997 :
998 1 : lockdep_init();
999 :
1000 : /*
1001 : * Need to run this when irqs are enabled, because it wants
1002 : * to self-test [hard/soft]-irqs on/off lock inversion bugs
1003 : * too:
1004 : */
1005 1 : locking_selftest();
1006 :
1007 : /*
1008 : * This needs to be called before any devices perform DMA
1009 : * operations that might use the SWIOTLB bounce buffers. It will
1010 : * mark the bounce buffers as decrypted so that their usage will
1011 : * not cause "plain-text" data to be decrypted when accessed.
1012 : */
1013 1 : mem_encrypt_init();
1014 :
1015 : #ifdef CONFIG_BLK_DEV_INITRD
1016 1 : if (initrd_start && !initrd_below_start_ok &&
1017 0 : page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
1018 0 : pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n",
1019 : page_to_pfn(virt_to_page((void *)initrd_start)),
1020 : min_low_pfn);
1021 0 : initrd_start = 0;
1022 : }
1023 : #endif
1024 1 : setup_per_cpu_pageset();
1025 1 : numa_policy_init();
1026 1 : acpi_early_init();
1027 1 : if (late_time_init)
1028 1 : late_time_init();
1029 1 : sched_clock_init();
1030 1 : calibrate_delay();
1031 1 : pid_idr_init();
1032 1 : anon_vma_init();
1033 : #ifdef CONFIG_X86
1034 1 : if (efi_enabled(EFI_RUNTIME_SERVICES))
1035 : efi_enter_virtual_mode();
1036 : #endif
1037 1 : thread_stack_cache_init();
1038 1 : cred_init();
1039 1 : fork_init();
1040 1 : proc_caches_init();
1041 1 : uts_ns_init();
1042 1 : key_init();
1043 1 : security_init();
1044 1 : dbg_late_init();
1045 1 : vfs_caches_init();
1046 1 : pagecache_init();
1047 1 : signals_init();
1048 1 : seq_file_init();
1049 1 : proc_root_init();
1050 1 : nsfs_init();
1051 1 : cpuset_init();
1052 1 : cgroup_init();
1053 1 : taskstats_init_early();
1054 1 : delayacct_init();
1055 :
1056 1 : poking_init();
1057 1 : check_bugs();
1058 :
1059 1 : acpi_subsystem_init();
1060 1 : arch_post_acpi_subsys_init();
1061 1 : kcsan_init();
1062 :
1063 : /* Do the rest non-__init'ed, we're now alive */
1064 1 : arch_call_rest_init();
1065 :
1066 0 : prevent_tail_call_optimization();
1067 0 : }
1068 :
1069 : /* Call all constructor functions linked into the kernel. */
1070 1 : static void __init do_ctors(void)
1071 : {
1072 : /*
1073 : * For UML, the constructors have already been called by the
1074 : * normal setup code as it's just a normal ELF binary, so we
1075 : * cannot do it again - but we do need CONFIG_CONSTRUCTORS
1076 : * even on UML for modules.
1077 : */
1078 : #if defined(CONFIG_CONSTRUCTORS) && !defined(CONFIG_UML)
1079 1 : ctor_fn_t *fn = (ctor_fn_t *) __ctors_start;
1080 :
1081 1902 : for (; fn < (ctor_fn_t *) __ctors_end; fn++)
1082 1901 : (*fn)();
1083 : #endif
1084 1 : }
1085 :
1086 : #ifdef CONFIG_KALLSYMS
1087 : struct blacklist_entry {
1088 : struct list_head next;
1089 : char *buf;
1090 : };
1091 :
1092 : static __initdata_or_module LIST_HEAD(blacklisted_initcalls);
1093 :
1094 0 : static int __init initcall_blacklist(char *str)
1095 : {
1096 0 : char *str_entry;
1097 0 : struct blacklist_entry *entry;
1098 :
1099 : /* str argument is a comma-separated list of functions */
1100 0 : do {
1101 0 : str_entry = strsep(&str, ",");
1102 0 : if (str_entry) {
1103 0 : pr_debug("blacklisting initcall %s\n", str_entry);
1104 0 : entry = memblock_alloc(sizeof(*entry),
1105 : SMP_CACHE_BYTES);
1106 0 : if (!entry)
1107 0 : panic("%s: Failed to allocate %zu bytes\n",
1108 : __func__, sizeof(*entry));
1109 0 : entry->buf = memblock_alloc(strlen(str_entry) + 1,
1110 : SMP_CACHE_BYTES);
1111 0 : if (!entry->buf)
1112 0 : panic("%s: Failed to allocate %zu bytes\n",
1113 0 : __func__, strlen(str_entry) + 1);
1114 0 : strcpy(entry->buf, str_entry);
1115 0 : list_add(&entry->next, &blacklisted_initcalls);
1116 : }
1117 0 : } while (str_entry);
1118 :
1119 0 : return 0;
1120 : }
1121 :
1122 256 : static bool __init_or_module initcall_blacklisted(initcall_t fn)
1123 : {
1124 256 : struct blacklist_entry *entry;
1125 256 : char fn_name[KSYM_SYMBOL_LEN];
1126 256 : unsigned long addr;
1127 :
1128 256 : if (list_empty(&blacklisted_initcalls))
1129 : return false;
1130 :
1131 0 : addr = (unsigned long) dereference_function_descriptor(fn);
1132 0 : sprint_symbol_no_offset(fn_name, addr);
1133 :
1134 : /*
1135 : * fn will be "function_name [module_name]" where [module_name] is not
1136 : * displayed for built-in init functions. Strip off the [module_name].
1137 : */
1138 0 : strreplace(fn_name, ' ', '\0');
1139 :
1140 0 : list_for_each_entry(entry, &blacklisted_initcalls, next) {
1141 0 : if (!strcmp(fn_name, entry->buf)) {
1142 0 : pr_debug("initcall %s blacklisted\n", fn_name);
1143 0 : return true;
1144 : }
1145 : }
1146 :
1147 : return false;
1148 : }
1149 : #else
1150 : static int __init initcall_blacklist(char *str)
1151 : {
1152 : pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n");
1153 : return 0;
1154 : }
1155 :
1156 : static bool __init_or_module initcall_blacklisted(initcall_t fn)
1157 : {
1158 : return false;
1159 : }
1160 : #endif
1161 : __setup("initcall_blacklist=", initcall_blacklist);
1162 :
1163 : static __init_or_module void
1164 0 : trace_initcall_start_cb(void *data, initcall_t fn)
1165 : {
1166 0 : ktime_t *calltime = (ktime_t *)data;
1167 :
1168 0 : printk(KERN_DEBUG "calling %pS @ %i\n", fn, task_pid_nr(current));
1169 0 : *calltime = ktime_get();
1170 0 : }
1171 :
1172 : static __init_or_module void
1173 0 : trace_initcall_finish_cb(void *data, initcall_t fn, int ret)
1174 : {
1175 0 : ktime_t *calltime = (ktime_t *)data;
1176 0 : ktime_t delta, rettime;
1177 0 : unsigned long long duration;
1178 :
1179 0 : rettime = ktime_get();
1180 0 : delta = ktime_sub(rettime, *calltime);
1181 0 : duration = (unsigned long long) ktime_to_ns(delta) >> 10;
1182 0 : printk(KERN_DEBUG "initcall %pS returned %d after %lld usecs\n",
1183 : fn, ret, duration);
1184 0 : }
1185 :
1186 : static ktime_t initcall_calltime;
1187 :
1188 : #ifdef TRACEPOINTS_ENABLED
1189 0 : static void __init initcall_debug_enable(void)
1190 : {
1191 0 : int ret;
1192 :
1193 0 : ret = register_trace_initcall_start(trace_initcall_start_cb,
1194 : &initcall_calltime);
1195 0 : ret |= register_trace_initcall_finish(trace_initcall_finish_cb,
1196 : &initcall_calltime);
1197 0 : WARN(ret, "Failed to register initcall tracepoints\n");
1198 0 : }
1199 : # define do_trace_initcall_start trace_initcall_start
1200 : # define do_trace_initcall_finish trace_initcall_finish
1201 : #else
1202 : static inline void do_trace_initcall_start(initcall_t fn)
1203 : {
1204 : if (!initcall_debug)
1205 : return;
1206 : trace_initcall_start_cb(&initcall_calltime, fn);
1207 : }
1208 : static inline void do_trace_initcall_finish(initcall_t fn, int ret)
1209 : {
1210 : if (!initcall_debug)
1211 : return;
1212 : trace_initcall_finish_cb(&initcall_calltime, fn, ret);
1213 : }
1214 : #endif /* !TRACEPOINTS_ENABLED */
1215 :
1216 256 : int __init_or_module do_one_initcall(initcall_t fn)
1217 : {
1218 256 : int count = preempt_count();
1219 256 : char msgbuf[64];
1220 256 : int ret;
1221 :
1222 256 : if (initcall_blacklisted(fn))
1223 : return -EPERM;
1224 :
1225 256 : do_trace_initcall_start(fn);
1226 256 : ret = fn();
1227 256 : do_trace_initcall_finish(fn, ret);
1228 :
1229 256 : msgbuf[0] = 0;
1230 :
1231 256 : if (preempt_count() != count) {
1232 0 : sprintf(msgbuf, "preemption imbalance ");
1233 0 : preempt_count_set(count);
1234 : }
1235 256 : if (irqs_disabled()) {
1236 0 : strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf));
1237 0 : local_irq_enable();
1238 : }
1239 256 : WARN(msgbuf[0], "initcall %pS returned with %s\n", fn, msgbuf);
1240 :
1241 : add_latent_entropy();
1242 : return ret;
1243 : }
1244 :
1245 :
1246 : extern initcall_entry_t __initcall_start[];
1247 : extern initcall_entry_t __initcall0_start[];
1248 : extern initcall_entry_t __initcall1_start[];
1249 : extern initcall_entry_t __initcall2_start[];
1250 : extern initcall_entry_t __initcall3_start[];
1251 : extern initcall_entry_t __initcall4_start[];
1252 : extern initcall_entry_t __initcall5_start[];
1253 : extern initcall_entry_t __initcall6_start[];
1254 : extern initcall_entry_t __initcall7_start[];
1255 : extern initcall_entry_t __initcall_end[];
1256 :
1257 : static initcall_entry_t *initcall_levels[] __initdata = {
1258 : __initcall0_start,
1259 : __initcall1_start,
1260 : __initcall2_start,
1261 : __initcall3_start,
1262 : __initcall4_start,
1263 : __initcall5_start,
1264 : __initcall6_start,
1265 : __initcall7_start,
1266 : __initcall_end,
1267 : };
1268 :
1269 : /* Keep these in sync with initcalls in include/linux/init.h */
1270 : static const char *initcall_level_names[] __initdata = {
1271 : "pure",
1272 : "core",
1273 : "postcore",
1274 : "arch",
1275 : "subsys",
1276 : "fs",
1277 : "device",
1278 : "late",
1279 : };
1280 :
1281 32 : static int __init ignore_unknown_bootoption(char *param, char *val,
1282 : const char *unused, void *arg)
1283 : {
1284 32 : return 0;
1285 : }
1286 :
1287 8 : static void __init do_initcall_level(int level, char *command_line)
1288 : {
1289 8 : initcall_entry_t *fn;
1290 :
1291 8 : parse_args(initcall_level_names[level],
1292 : command_line, __start___param,
1293 8 : __stop___param - __start___param,
1294 : level, level,
1295 : NULL, ignore_unknown_bootoption);
1296 :
1297 8 : trace_initcall_level(initcall_level_names[level]);
1298 243 : for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++)
1299 235 : do_one_initcall(initcall_from_entry(fn));
1300 8 : }
1301 :
1302 1 : static void __init do_initcalls(void)
1303 : {
1304 1 : int level;
1305 1 : size_t len = strlen(saved_command_line) + 1;
1306 1 : char *command_line;
1307 :
1308 1 : command_line = kzalloc(len, GFP_KERNEL);
1309 1 : if (!command_line)
1310 0 : panic("%s: Failed to allocate %zu bytes\n", __func__, len);
1311 :
1312 9 : for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) {
1313 : /* Parser modifies command_line, restore it each time */
1314 8 : strcpy(command_line, saved_command_line);
1315 8 : do_initcall_level(level, command_line);
1316 : }
1317 :
1318 1 : kfree(command_line);
1319 1 : }
1320 :
1321 : /*
1322 : * Ok, the machine is now initialized. None of the devices
1323 : * have been touched yet, but the CPU subsystem is up and
1324 : * running, and memory and process management works.
1325 : *
1326 : * Now we can finally start doing some real work..
1327 : */
1328 1 : static void __init do_basic_setup(void)
1329 : {
1330 1 : cpuset_init_smp();
1331 1 : driver_init();
1332 1 : init_irq_proc();
1333 1 : do_ctors();
1334 1 : usermodehelper_enable();
1335 1 : do_initcalls();
1336 1 : }
1337 :
1338 1 : static void __init do_pre_smp_initcalls(void)
1339 : {
1340 1 : initcall_entry_t *fn;
1341 :
1342 1 : trace_initcall_level("early");
1343 23 : for (fn = __initcall_start; fn < __initcall0_start; fn++)
1344 21 : do_one_initcall(initcall_from_entry(fn));
1345 1 : }
1346 :
1347 1 : static int run_init_process(const char *init_filename)
1348 : {
1349 1 : const char *const *p;
1350 :
1351 1 : argv_init[0] = init_filename;
1352 1 : pr_info("Run %s as init process\n", init_filename);
1353 1 : pr_debug(" with arguments:\n");
1354 3 : for (p = argv_init; *p; p++)
1355 1 : pr_debug(" %s\n", *p);
1356 1 : pr_debug(" with environment:\n");
1357 4 : for (p = envp_init; *p; p++)
1358 2 : pr_debug(" %s\n", *p);
1359 1 : return kernel_execve(init_filename, argv_init, envp_init);
1360 : }
1361 :
1362 1 : static int try_to_run_init_process(const char *init_filename)
1363 : {
1364 1 : int ret;
1365 :
1366 1 : ret = run_init_process(init_filename);
1367 :
1368 1 : if (ret && ret != -ENOENT) {
1369 0 : pr_err("Starting init: %s exists but couldn't execute it (error %d)\n",
1370 : init_filename, ret);
1371 : }
1372 :
1373 1 : return ret;
1374 : }
1375 :
1376 : static noinline void __init kernel_init_freeable(void);
1377 :
1378 : #if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX)
1379 : bool rodata_enabled __ro_after_init = true;
1380 0 : static int __init set_debug_rodata(char *str)
1381 : {
1382 0 : return strtobool(str, &rodata_enabled);
1383 : }
1384 : __setup("rodata=", set_debug_rodata);
1385 : #endif
1386 :
1387 : #ifdef CONFIG_STRICT_KERNEL_RWX
1388 1 : static void mark_readonly(void)
1389 : {
1390 1 : if (rodata_enabled) {
1391 : /*
1392 : * load_module() results in W+X mappings, which are cleaned
1393 : * up with call_rcu(). Let's make sure that queued work is
1394 : * flushed so that we don't hit false positives looking for
1395 : * insecure pages which are W+X.
1396 : */
1397 1 : rcu_barrier();
1398 1 : mark_rodata_ro();
1399 1 : rodata_test();
1400 : } else
1401 0 : pr_info("Kernel memory protection disabled.\n");
1402 1 : }
1403 : #elif defined(CONFIG_ARCH_HAS_STRICT_KERNEL_RWX)
1404 : static inline void mark_readonly(void)
1405 : {
1406 : pr_warn("Kernel memory protection not selected by kernel config.\n");
1407 : }
1408 : #else
1409 : static inline void mark_readonly(void)
1410 : {
1411 : pr_warn("This architecture does not have kernel memory protection.\n");
1412 : }
1413 : #endif
1414 :
1415 0 : void __weak free_initmem(void)
1416 : {
1417 0 : free_initmem_default(POISON_FREE_INITMEM);
1418 0 : }
1419 :
1420 1 : static int __ref kernel_init(void *unused)
1421 : {
1422 1 : int ret;
1423 :
1424 1 : kernel_init_freeable();
1425 : /* need to finish all async __init code before freeing the memory */
1426 1 : async_synchronize_full();
1427 1 : kprobe_free_init_mem();
1428 1 : ftrace_free_init_mem();
1429 1 : kgdb_free_init_mem();
1430 1 : free_initmem();
1431 1 : mark_readonly();
1432 :
1433 : /*
1434 : * Kernel mappings are now finalized - update the userspace page-table
1435 : * to finalize PTI.
1436 : */
1437 1 : pti_finalize();
1438 :
1439 1 : system_state = SYSTEM_RUNNING;
1440 1 : numa_default_policy();
1441 :
1442 1 : rcu_end_inkernel_boot();
1443 :
1444 1 : do_sysctl_args();
1445 :
1446 1 : if (ramdisk_execute_command) {
1447 0 : ret = run_init_process(ramdisk_execute_command);
1448 0 : if (!ret)
1449 : return 0;
1450 0 : pr_err("Failed to execute %s (error %d)\n",
1451 : ramdisk_execute_command, ret);
1452 : }
1453 :
1454 : /*
1455 : * We try each of these until one succeeds.
1456 : *
1457 : * The Bourne shell can be used instead of init if we are
1458 : * trying to recover a really broken machine.
1459 : */
1460 1 : if (execute_command) {
1461 0 : ret = run_init_process(execute_command);
1462 0 : if (!ret)
1463 : return 0;
1464 0 : panic("Requested init %s failed (error %d).",
1465 : execute_command, ret);
1466 : }
1467 :
1468 1 : if (CONFIG_DEFAULT_INIT[0] != '\0') {
1469 : ret = run_init_process(CONFIG_DEFAULT_INIT);
1470 : if (ret)
1471 : pr_err("Default init %s failed (error %d)\n",
1472 : CONFIG_DEFAULT_INIT, ret);
1473 : else
1474 : return 0;
1475 : }
1476 :
1477 1 : if (!try_to_run_init_process("/sbin/init") ||
1478 0 : !try_to_run_init_process("/etc/init") ||
1479 0 : !try_to_run_init_process("/bin/init") ||
1480 0 : !try_to_run_init_process("/bin/sh"))
1481 1 : return 0;
1482 :
1483 0 : panic("No working init found. Try passing init= option to kernel. "
1484 : "See Linux Documentation/admin-guide/init.rst for guidance.");
1485 : }
1486 :
1487 : /* Open /dev/console, for stdin/stdout/stderr, this should never fail */
1488 1 : void __init console_on_rootfs(void)
1489 : {
1490 1 : struct file *file = filp_open("/dev/console", O_RDWR, 0);
1491 :
1492 1 : if (IS_ERR(file)) {
1493 0 : pr_err("Warning: unable to open an initial console.\n");
1494 0 : return;
1495 : }
1496 1 : init_dup(file);
1497 1 : init_dup(file);
1498 1 : init_dup(file);
1499 1 : fput(file);
1500 : }
1501 :
1502 1 : static noinline void __init kernel_init_freeable(void)
1503 : {
1504 : /*
1505 : * Wait until kthreadd is all set-up.
1506 : */
1507 1 : wait_for_completion(&kthreadd_done);
1508 :
1509 : /* Now the scheduler is fully set up and can do blocking allocations */
1510 1 : gfp_allowed_mask = __GFP_BITS_MASK;
1511 :
1512 : /*
1513 : * init can allocate pages on any node
1514 : */
1515 1 : set_mems_allowed(node_states[N_MEMORY]);
1516 :
1517 1 : cad_pid = task_pid(current);
1518 :
1519 1 : smp_prepare_cpus(setup_max_cpus);
1520 :
1521 1 : workqueue_init();
1522 :
1523 1 : init_mm_internals();
1524 :
1525 1 : rcu_init_tasks_generic();
1526 1 : do_pre_smp_initcalls();
1527 1 : lockup_detector_init();
1528 :
1529 1 : smp_init();
1530 1 : sched_init_smp();
1531 :
1532 1 : padata_init();
1533 1 : page_alloc_init_late();
1534 : /* Initialize page ext after all struct pages are initialized. */
1535 1 : page_ext_init();
1536 :
1537 1 : do_basic_setup();
1538 :
1539 1 : kunit_run_all_tests();
1540 :
1541 1 : console_on_rootfs();
1542 :
1543 : /*
1544 : * check if there is an early userspace init. If yes, let it do all
1545 : * the work
1546 : */
1547 1 : if (init_eaccess(ramdisk_execute_command) != 0) {
1548 1 : ramdisk_execute_command = NULL;
1549 1 : prepare_namespace();
1550 : }
1551 :
1552 : /*
1553 : * Ok, we have completed the initial bootup, and
1554 : * we're essentially up and running. Get rid of the
1555 : * initmem segments and start the user-mode stuff..
1556 : *
1557 : * rootfs is available now, try loading the public keys
1558 : * and default modules
1559 : */
1560 :
1561 1 : integrity_load_keys();
1562 1 : }
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