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/debug_locks.h> |
66 | #include <linux/debugobjects.h> |
67 | #include <linux/lockdep.h> |
68 | #include <linux/kmemleak.h> |
69 | #include <linux/padata.h> |
70 | #include <linux/pid_namespace.h> |
71 | #include <linux/device/driver.h> |
72 | #include <linux/kthread.h> |
73 | #include <linux/sched.h> |
74 | #include <linux/sched/init.h> |
75 | #include <linux/signal.h> |
76 | #include <linux/idr.h> |
77 | #include <linux/kgdb.h> |
78 | #include <linux/ftrace.h> |
79 | #include <linux/async.h> |
80 | #include <linux/shmem_fs.h> |
81 | #include <linux/slab.h> |
82 | #include <linux/perf_event.h> |
83 | #include <linux/ptrace.h> |
84 | #include <linux/pti.h> |
85 | #include <linux/blkdev.h> |
86 | #include <linux/sched/clock.h> |
87 | #include <linux/sched/task.h> |
88 | #include <linux/sched/task_stack.h> |
89 | #include <linux/context_tracking.h> |
90 | #include <linux/random.h> |
91 | #include <linux/list.h> |
92 | #include <linux/integrity.h> |
93 | #include <linux/proc_ns.h> |
94 | #include <linux/io.h> |
95 | #include <linux/cache.h> |
96 | #include <linux/rodata_test.h> |
97 | #include <linux/jump_label.h> |
98 | #include <linux/kcsan.h> |
99 | #include <linux/init_syscalls.h> |
100 | #include <linux/stackdepot.h> |
101 | #include <linux/randomize_kstack.h> |
102 | #include <net/net_namespace.h> |
103 | |
104 | #include <asm/io.h> |
105 | #include <asm/setup.h> |
106 | #include <asm/sections.h> |
107 | #include <asm/cacheflush.h> |
108 | |
109 | #define CREATE_TRACE_POINTS |
110 | #include <trace/events/initcall.h> |
111 | |
112 | #include <kunit/test.h> |
113 | |
114 | static int kernel_init(void *); |
115 | |
116 | /* |
117 | * Debug helper: via this flag we know that we are in 'early bootup code' |
118 | * where only the boot processor is running with IRQ disabled. This means |
119 | * two things - IRQ must not be enabled before the flag is cleared and some |
120 | * operations which are not allowed with IRQ disabled are allowed while the |
121 | * flag is set. |
122 | */ |
123 | bool early_boot_irqs_disabled __read_mostly; |
124 | |
125 | enum system_states system_state __read_mostly; |
126 | EXPORT_SYMBOL(system_state); |
127 | |
128 | /* |
129 | * Boot command-line arguments |
130 | */ |
131 | #define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT |
132 | #define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT |
133 | |
134 | /* Default late time init is NULL. archs can override this later. */ |
135 | void (*__initdata late_time_init)(void); |
136 | |
137 | /* Untouched command line saved by arch-specific code. */ |
138 | char __initdata boot_command_line[COMMAND_LINE_SIZE]; |
139 | /* Untouched saved command line (eg. for /proc) */ |
140 | char *saved_command_line __ro_after_init; |
141 | unsigned int saved_command_line_len __ro_after_init; |
142 | /* Command line for parameter parsing */ |
143 | static char *static_command_line; |
144 | /* Untouched extra command line */ |
145 | static char *extra_command_line; |
146 | /* Extra init arguments */ |
147 | static char *; |
148 | |
149 | #ifdef CONFIG_BOOT_CONFIG |
150 | /* Is bootconfig on command line? */ |
151 | static bool bootconfig_found; |
152 | static size_t initargs_offs; |
153 | #else |
154 | # define bootconfig_found false |
155 | # define initargs_offs 0 |
156 | #endif |
157 | |
158 | static char *execute_command; |
159 | static char *ramdisk_execute_command = "/init" ; |
160 | |
161 | /* |
162 | * Used to generate warnings if static_key manipulation functions are used |
163 | * before jump_label_init is called. |
164 | */ |
165 | bool static_key_initialized __read_mostly; |
166 | EXPORT_SYMBOL_GPL(static_key_initialized); |
167 | |
168 | /* |
169 | * If set, this is an indication to the drivers that reset the underlying |
170 | * device before going ahead with the initialization otherwise driver might |
171 | * rely on the BIOS and skip the reset operation. |
172 | * |
173 | * This is useful if kernel is booting in an unreliable environment. |
174 | * For ex. kdump situation where previous kernel has crashed, BIOS has been |
175 | * skipped and devices will be in unknown state. |
176 | */ |
177 | unsigned int reset_devices; |
178 | EXPORT_SYMBOL(reset_devices); |
179 | |
180 | static int __init set_reset_devices(char *str) |
181 | { |
182 | reset_devices = 1; |
183 | return 1; |
184 | } |
185 | |
186 | __setup("reset_devices" , set_reset_devices); |
187 | |
188 | static const char *argv_init[MAX_INIT_ARGS+2] = { "init" , NULL, }; |
189 | const char *envp_init[MAX_INIT_ENVS+2] = { "HOME=/" , "TERM=linux" , NULL, }; |
190 | static const char *panic_later, *panic_param; |
191 | |
192 | static bool __init obsolete_checksetup(char *line) |
193 | { |
194 | const struct obs_kernel_param *p; |
195 | bool had_early_param = false; |
196 | |
197 | p = __setup_start; |
198 | do { |
199 | int n = strlen(p->str); |
200 | if (parameqn(name1: line, name2: p->str, n)) { |
201 | if (p->early) { |
202 | /* Already done in parse_early_param? |
203 | * (Needs exact match on param part). |
204 | * Keep iterating, as we can have early |
205 | * params and __setups of same names 8( */ |
206 | if (line[n] == '\0' || line[n] == '=') |
207 | had_early_param = true; |
208 | } else if (!p->setup_func) { |
209 | pr_warn("Parameter %s is obsolete, ignored\n" , |
210 | p->str); |
211 | return true; |
212 | } else if (p->setup_func(line + n)) |
213 | return true; |
214 | } |
215 | p++; |
216 | } while (p < __setup_end); |
217 | |
218 | return had_early_param; |
219 | } |
220 | |
221 | /* |
222 | * This should be approx 2 Bo*oMips to start (note initial shift), and will |
223 | * still work even if initially too large, it will just take slightly longer |
224 | */ |
225 | unsigned long loops_per_jiffy = (1<<12); |
226 | EXPORT_SYMBOL(loops_per_jiffy); |
227 | |
228 | static int __init debug_kernel(char *str) |
229 | { |
230 | console_loglevel = CONSOLE_LOGLEVEL_DEBUG; |
231 | return 0; |
232 | } |
233 | |
234 | static int __init quiet_kernel(char *str) |
235 | { |
236 | console_loglevel = CONSOLE_LOGLEVEL_QUIET; |
237 | return 0; |
238 | } |
239 | |
240 | early_param("debug" , debug_kernel); |
241 | early_param("quiet" , quiet_kernel); |
242 | |
243 | static int __init loglevel(char *str) |
244 | { |
245 | int newlevel; |
246 | |
247 | /* |
248 | * Only update loglevel value when a correct setting was passed, |
249 | * to prevent blind crashes (when loglevel being set to 0) that |
250 | * are quite hard to debug |
251 | */ |
252 | if (get_option(str: &str, pint: &newlevel)) { |
253 | console_loglevel = newlevel; |
254 | return 0; |
255 | } |
256 | |
257 | return -EINVAL; |
258 | } |
259 | |
260 | early_param("loglevel" , loglevel); |
261 | |
262 | #ifdef CONFIG_BLK_DEV_INITRD |
263 | static void * __init get_boot_config_from_initrd(size_t *_size) |
264 | { |
265 | u32 size, csum; |
266 | char *data; |
267 | u32 *hdr; |
268 | int i; |
269 | |
270 | if (!initrd_end) |
271 | return NULL; |
272 | |
273 | data = (char *)initrd_end - BOOTCONFIG_MAGIC_LEN; |
274 | /* |
275 | * Since Grub may align the size of initrd to 4, we must |
276 | * check the preceding 3 bytes as well. |
277 | */ |
278 | for (i = 0; i < 4; i++) { |
279 | if (!memcmp(p: data, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN)) |
280 | goto found; |
281 | data--; |
282 | } |
283 | return NULL; |
284 | |
285 | found: |
286 | hdr = (u32 *)(data - 8); |
287 | size = le32_to_cpu(hdr[0]); |
288 | csum = le32_to_cpu(hdr[1]); |
289 | |
290 | data = ((void *)hdr) - size; |
291 | if ((unsigned long)data < initrd_start) { |
292 | pr_err("bootconfig size %d is greater than initrd size %ld\n" , |
293 | size, initrd_end - initrd_start); |
294 | return NULL; |
295 | } |
296 | |
297 | if (xbc_calc_checksum(data, size) != csum) { |
298 | pr_err("bootconfig checksum failed\n" ); |
299 | return NULL; |
300 | } |
301 | |
302 | /* Remove bootconfig from initramfs/initrd */ |
303 | initrd_end = (unsigned long)data; |
304 | if (_size) |
305 | *_size = size; |
306 | |
307 | return data; |
308 | } |
309 | #else |
310 | static void * __init get_boot_config_from_initrd(size_t *_size) |
311 | { |
312 | return NULL; |
313 | } |
314 | #endif |
315 | |
316 | #ifdef CONFIG_BOOT_CONFIG |
317 | |
318 | static char xbc_namebuf[XBC_KEYLEN_MAX] __initdata; |
319 | |
320 | #define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0) |
321 | |
322 | static int __init xbc_snprint_cmdline(char *buf, size_t size, |
323 | struct xbc_node *root) |
324 | { |
325 | struct xbc_node *knode, *vnode; |
326 | char *end = buf + size; |
327 | const char *val; |
328 | int ret; |
329 | |
330 | xbc_node_for_each_key_value(root, knode, val) { |
331 | ret = xbc_node_compose_key_after(root, node: knode, |
332 | buf: xbc_namebuf, XBC_KEYLEN_MAX); |
333 | if (ret < 0) |
334 | return ret; |
335 | |
336 | vnode = xbc_node_get_child(node: knode); |
337 | if (!vnode) { |
338 | ret = snprintf(buf, rest(buf, end), fmt: "%s " , xbc_namebuf); |
339 | if (ret < 0) |
340 | return ret; |
341 | buf += ret; |
342 | continue; |
343 | } |
344 | xbc_array_for_each_value(vnode, val) { |
345 | ret = snprintf(buf, rest(buf, end), fmt: "%s=\"%s\" " , |
346 | xbc_namebuf, val); |
347 | if (ret < 0) |
348 | return ret; |
349 | buf += ret; |
350 | } |
351 | } |
352 | |
353 | return buf - (end - size); |
354 | } |
355 | #undef rest |
356 | |
357 | /* Make an extra command line under given key word */ |
358 | static char * __init xbc_make_cmdline(const char *key) |
359 | { |
360 | struct xbc_node *root; |
361 | char *new_cmdline; |
362 | int ret, len = 0; |
363 | |
364 | root = xbc_find_node(key); |
365 | if (!root) |
366 | return NULL; |
367 | |
368 | /* Count required buffer size */ |
369 | len = xbc_snprint_cmdline(NULL, size: 0, root); |
370 | if (len <= 0) |
371 | return NULL; |
372 | |
373 | new_cmdline = memblock_alloc(size: len + 1, SMP_CACHE_BYTES); |
374 | if (!new_cmdline) { |
375 | pr_err("Failed to allocate memory for extra kernel cmdline.\n" ); |
376 | return NULL; |
377 | } |
378 | |
379 | ret = xbc_snprint_cmdline(buf: new_cmdline, size: len + 1, root); |
380 | if (ret < 0 || ret > len) { |
381 | pr_err("Failed to print extra kernel cmdline.\n" ); |
382 | memblock_free(ptr: new_cmdline, size: len + 1); |
383 | return NULL; |
384 | } |
385 | |
386 | return new_cmdline; |
387 | } |
388 | |
389 | static int __init bootconfig_params(char *param, char *val, |
390 | const char *unused, void *arg) |
391 | { |
392 | if (strcmp(param, "bootconfig" ) == 0) { |
393 | bootconfig_found = true; |
394 | } |
395 | return 0; |
396 | } |
397 | |
398 | static int __init warn_bootconfig(char *str) |
399 | { |
400 | /* The 'bootconfig' has been handled by bootconfig_params(). */ |
401 | return 0; |
402 | } |
403 | |
404 | static void __init setup_boot_config(void) |
405 | { |
406 | static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; |
407 | const char *msg, *data; |
408 | int pos, ret; |
409 | size_t size; |
410 | char *err; |
411 | |
412 | /* Cut out the bootconfig data even if we have no bootconfig option */ |
413 | data = get_boot_config_from_initrd(size: &size); |
414 | /* If there is no bootconfig in initrd, try embedded one. */ |
415 | if (!data) |
416 | data = xbc_get_embedded_bootconfig(size: &size); |
417 | |
418 | strscpy(p: tmp_cmdline, q: boot_command_line, COMMAND_LINE_SIZE); |
419 | err = parse_args(name: "bootconfig" , args: tmp_cmdline, NULL, num: 0, level_min: 0, level_max: 0, NULL, |
420 | unknown: bootconfig_params); |
421 | |
422 | if (IS_ERR(ptr: err) || !(bootconfig_found || IS_ENABLED(CONFIG_BOOT_CONFIG_FORCE))) |
423 | return; |
424 | |
425 | /* parse_args() stops at the next param of '--' and returns an address */ |
426 | if (err) |
427 | initargs_offs = err - tmp_cmdline; |
428 | |
429 | if (!data) { |
430 | /* If user intended to use bootconfig, show an error level message */ |
431 | if (bootconfig_found) |
432 | pr_err("'bootconfig' found on command line, but no bootconfig found\n" ); |
433 | else |
434 | pr_info("No bootconfig data provided, so skipping bootconfig" ); |
435 | return; |
436 | } |
437 | |
438 | if (size >= XBC_DATA_MAX) { |
439 | pr_err("bootconfig size %ld greater than max size %d\n" , |
440 | (long)size, XBC_DATA_MAX); |
441 | return; |
442 | } |
443 | |
444 | ret = xbc_init(buf: data, size, emsg: &msg, epos: &pos); |
445 | if (ret < 0) { |
446 | if (pos < 0) |
447 | pr_err("Failed to init bootconfig: %s.\n" , msg); |
448 | else |
449 | pr_err("Failed to parse bootconfig: %s at %d.\n" , |
450 | msg, pos); |
451 | } else { |
452 | xbc_get_info(node_size: &ret, NULL); |
453 | pr_info("Load bootconfig: %ld bytes %d nodes\n" , (long)size, ret); |
454 | /* keys starting with "kernel." are passed via cmdline */ |
455 | extra_command_line = xbc_make_cmdline(key: "kernel" ); |
456 | /* Also, "init." keys are init arguments */ |
457 | extra_init_args = xbc_make_cmdline(key: "init" ); |
458 | } |
459 | return; |
460 | } |
461 | |
462 | static void __init exit_boot_config(void) |
463 | { |
464 | xbc_exit(); |
465 | } |
466 | |
467 | #else /* !CONFIG_BOOT_CONFIG */ |
468 | |
469 | static void __init setup_boot_config(void) |
470 | { |
471 | /* Remove bootconfig data from initrd */ |
472 | get_boot_config_from_initrd(NULL); |
473 | } |
474 | |
475 | static int __init warn_bootconfig(char *str) |
476 | { |
477 | pr_warn("WARNING: 'bootconfig' found on the kernel command line but CONFIG_BOOT_CONFIG is not set.\n" ); |
478 | return 0; |
479 | } |
480 | |
481 | #define exit_boot_config() do {} while (0) |
482 | |
483 | #endif /* CONFIG_BOOT_CONFIG */ |
484 | |
485 | early_param("bootconfig" , warn_bootconfig); |
486 | |
487 | /* Change NUL term back to "=", to make "param" the whole string. */ |
488 | static void __init repair_env_string(char *param, char *val) |
489 | { |
490 | if (val) { |
491 | /* param=val or param="val"? */ |
492 | if (val == param+strlen(param)+1) |
493 | val[-1] = '='; |
494 | else if (val == param+strlen(param)+2) { |
495 | val[-2] = '='; |
496 | memmove(val-1, val, strlen(val)+1); |
497 | } else |
498 | BUG(); |
499 | } |
500 | } |
501 | |
502 | /* Anything after -- gets handed straight to init. */ |
503 | static int __init set_init_arg(char *param, char *val, |
504 | const char *unused, void *arg) |
505 | { |
506 | unsigned int i; |
507 | |
508 | if (panic_later) |
509 | return 0; |
510 | |
511 | repair_env_string(param, val); |
512 | |
513 | for (i = 0; argv_init[i]; i++) { |
514 | if (i == MAX_INIT_ARGS) { |
515 | panic_later = "init" ; |
516 | panic_param = param; |
517 | return 0; |
518 | } |
519 | } |
520 | argv_init[i] = param; |
521 | return 0; |
522 | } |
523 | |
524 | /* |
525 | * Unknown boot options get handed to init, unless they look like |
526 | * unused parameters (modprobe will find them in /proc/cmdline). |
527 | */ |
528 | static int __init unknown_bootoption(char *param, char *val, |
529 | const char *unused, void *arg) |
530 | { |
531 | size_t len = strlen(param); |
532 | |
533 | /* Handle params aliased to sysctls */ |
534 | if (sysctl_is_alias(param)) |
535 | return 0; |
536 | |
537 | repair_env_string(param, val); |
538 | |
539 | /* Handle obsolete-style parameters */ |
540 | if (obsolete_checksetup(line: param)) |
541 | return 0; |
542 | |
543 | /* Unused module parameter. */ |
544 | if (strnchr(param, len, '.')) |
545 | return 0; |
546 | |
547 | if (panic_later) |
548 | return 0; |
549 | |
550 | if (val) { |
551 | /* Environment option */ |
552 | unsigned int i; |
553 | for (i = 0; envp_init[i]; i++) { |
554 | if (i == MAX_INIT_ENVS) { |
555 | panic_later = "env" ; |
556 | panic_param = param; |
557 | } |
558 | if (!strncmp(param, envp_init[i], len+1)) |
559 | break; |
560 | } |
561 | envp_init[i] = param; |
562 | } else { |
563 | /* Command line option */ |
564 | unsigned int i; |
565 | for (i = 0; argv_init[i]; i++) { |
566 | if (i == MAX_INIT_ARGS) { |
567 | panic_later = "init" ; |
568 | panic_param = param; |
569 | } |
570 | } |
571 | argv_init[i] = param; |
572 | } |
573 | return 0; |
574 | } |
575 | |
576 | static int __init init_setup(char *str) |
577 | { |
578 | unsigned int i; |
579 | |
580 | execute_command = str; |
581 | /* |
582 | * In case LILO is going to boot us with default command line, |
583 | * it prepends "auto" before the whole cmdline which makes |
584 | * the shell think it should execute a script with such name. |
585 | * So we ignore all arguments entered _before_ init=... [MJ] |
586 | */ |
587 | for (i = 1; i < MAX_INIT_ARGS; i++) |
588 | argv_init[i] = NULL; |
589 | return 1; |
590 | } |
591 | __setup("init=" , init_setup); |
592 | |
593 | static int __init rdinit_setup(char *str) |
594 | { |
595 | unsigned int i; |
596 | |
597 | ramdisk_execute_command = str; |
598 | /* See "auto" comment in init_setup */ |
599 | for (i = 1; i < MAX_INIT_ARGS; i++) |
600 | argv_init[i] = NULL; |
601 | return 1; |
602 | } |
603 | __setup("rdinit=" , rdinit_setup); |
604 | |
605 | #ifndef CONFIG_SMP |
606 | static const unsigned int setup_max_cpus = NR_CPUS; |
607 | static inline void setup_nr_cpu_ids(void) { } |
608 | static inline void smp_prepare_cpus(unsigned int maxcpus) { } |
609 | #endif |
610 | |
611 | /* |
612 | * We need to store the untouched command line for future reference. |
613 | * We also need to store the touched command line since the parameter |
614 | * parsing is performed in place, and we should allow a component to |
615 | * store reference of name/value for future reference. |
616 | */ |
617 | static void __init setup_command_line(char *command_line) |
618 | { |
619 | size_t len, xlen = 0, ilen = 0; |
620 | |
621 | if (extra_command_line) |
622 | xlen = strlen(extra_command_line); |
623 | if (extra_init_args) |
624 | ilen = strlen(extra_init_args) + 4; /* for " -- " */ |
625 | |
626 | len = xlen + strlen(boot_command_line) + 1; |
627 | |
628 | saved_command_line = memblock_alloc(size: len + ilen, SMP_CACHE_BYTES); |
629 | if (!saved_command_line) |
630 | panic(fmt: "%s: Failed to allocate %zu bytes\n" , __func__, len + ilen); |
631 | |
632 | static_command_line = memblock_alloc(size: len, SMP_CACHE_BYTES); |
633 | if (!static_command_line) |
634 | panic(fmt: "%s: Failed to allocate %zu bytes\n" , __func__, len); |
635 | |
636 | if (xlen) { |
637 | /* |
638 | * We have to put extra_command_line before boot command |
639 | * lines because there could be dashes (separator of init |
640 | * command line) in the command lines. |
641 | */ |
642 | strcpy(p: saved_command_line, q: extra_command_line); |
643 | strcpy(p: static_command_line, q: extra_command_line); |
644 | } |
645 | strcpy(p: saved_command_line + xlen, q: boot_command_line); |
646 | strcpy(p: static_command_line + xlen, q: command_line); |
647 | |
648 | if (ilen) { |
649 | /* |
650 | * Append supplemental init boot args to saved_command_line |
651 | * so that user can check what command line options passed |
652 | * to init. |
653 | * The order should always be |
654 | * " -- "[bootconfig init-param][cmdline init-param] |
655 | */ |
656 | if (initargs_offs) { |
657 | len = xlen + initargs_offs; |
658 | strcpy(p: saved_command_line + len, q: extra_init_args); |
659 | len += ilen - 4; /* strlen(extra_init_args) */ |
660 | strcpy(p: saved_command_line + len, |
661 | q: boot_command_line + initargs_offs - 1); |
662 | } else { |
663 | len = strlen(saved_command_line); |
664 | strcpy(p: saved_command_line + len, q: " -- " ); |
665 | len += 4; |
666 | strcpy(p: saved_command_line + len, q: extra_init_args); |
667 | } |
668 | } |
669 | |
670 | saved_command_line_len = strlen(saved_command_line); |
671 | } |
672 | |
673 | /* |
674 | * We need to finalize in a non-__init function or else race conditions |
675 | * between the root thread and the init thread may cause start_kernel to |
676 | * be reaped by free_initmem before the root thread has proceeded to |
677 | * cpu_idle. |
678 | * |
679 | * gcc-3.4 accidentally inlines this function, so use noinline. |
680 | */ |
681 | |
682 | static __initdata DECLARE_COMPLETION(kthreadd_done); |
683 | |
684 | noinline void __ref __noreturn rest_init(void) |
685 | { |
686 | struct task_struct *tsk; |
687 | int pid; |
688 | |
689 | rcu_scheduler_starting(); |
690 | /* |
691 | * We need to spawn init first so that it obtains pid 1, however |
692 | * the init task will end up wanting to create kthreads, which, if |
693 | * we schedule it before we create kthreadd, will OOPS. |
694 | */ |
695 | pid = user_mode_thread(fn: kernel_init, NULL, CLONE_FS); |
696 | /* |
697 | * Pin init on the boot CPU. Task migration is not properly working |
698 | * until sched_init_smp() has been run. It will set the allowed |
699 | * CPUs for init to the non isolated CPUs. |
700 | */ |
701 | rcu_read_lock(); |
702 | tsk = find_task_by_pid_ns(nr: pid, ns: &init_pid_ns); |
703 | tsk->flags |= PF_NO_SETAFFINITY; |
704 | set_cpus_allowed_ptr(p: tsk, cpumask_of(smp_processor_id())); |
705 | rcu_read_unlock(); |
706 | |
707 | numa_default_policy(); |
708 | pid = kernel_thread(fn: kthreadd, NULL, NULL, CLONE_FS | CLONE_FILES); |
709 | rcu_read_lock(); |
710 | kthreadd_task = find_task_by_pid_ns(nr: pid, ns: &init_pid_ns); |
711 | rcu_read_unlock(); |
712 | |
713 | /* |
714 | * Enable might_sleep() and smp_processor_id() checks. |
715 | * They cannot be enabled earlier because with CONFIG_PREEMPTION=y |
716 | * kernel_thread() would trigger might_sleep() splats. With |
717 | * CONFIG_PREEMPT_VOLUNTARY=y the init task might have scheduled |
718 | * already, but it's stuck on the kthreadd_done completion. |
719 | */ |
720 | system_state = SYSTEM_SCHEDULING; |
721 | |
722 | complete(&kthreadd_done); |
723 | |
724 | /* |
725 | * The boot idle thread must execute schedule() |
726 | * at least once to get things moving: |
727 | */ |
728 | schedule_preempt_disabled(); |
729 | /* Call into cpu_idle with preempt disabled */ |
730 | cpu_startup_entry(state: CPUHP_ONLINE); |
731 | } |
732 | |
733 | /* Check for early params. */ |
734 | static int __init do_early_param(char *param, char *val, |
735 | const char *unused, void *arg) |
736 | { |
737 | const struct obs_kernel_param *p; |
738 | |
739 | for (p = __setup_start; p < __setup_end; p++) { |
740 | if ((p->early && parameq(name1: param, name2: p->str)) || |
741 | (strcmp(param, "console" ) == 0 && |
742 | strcmp(p->str, "earlycon" ) == 0) |
743 | ) { |
744 | if (p->setup_func(val) != 0) |
745 | pr_warn("Malformed early option '%s'\n" , param); |
746 | } |
747 | } |
748 | /* We accept everything at this stage. */ |
749 | return 0; |
750 | } |
751 | |
752 | void __init parse_early_options(char *cmdline) |
753 | { |
754 | parse_args(name: "early options" , args: cmdline, NULL, num: 0, level_min: 0, level_max: 0, NULL, |
755 | unknown: do_early_param); |
756 | } |
757 | |
758 | /* Arch code calls this early on, or if not, just before other parsing. */ |
759 | void __init parse_early_param(void) |
760 | { |
761 | static int done __initdata; |
762 | static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; |
763 | |
764 | if (done) |
765 | return; |
766 | |
767 | /* All fall through to do_early_param. */ |
768 | strscpy(p: tmp_cmdline, q: boot_command_line, COMMAND_LINE_SIZE); |
769 | parse_early_options(cmdline: tmp_cmdline); |
770 | done = 1; |
771 | } |
772 | |
773 | void __init __weak arch_post_acpi_subsys_init(void) { } |
774 | |
775 | void __init __weak smp_setup_processor_id(void) |
776 | { |
777 | } |
778 | |
779 | # if THREAD_SIZE >= PAGE_SIZE |
780 | void __init __weak thread_stack_cache_init(void) |
781 | { |
782 | } |
783 | #endif |
784 | |
785 | void __init __weak poking_init(void) { } |
786 | |
787 | void __init __weak pgtable_cache_init(void) { } |
788 | |
789 | void __init __weak trap_init(void) { } |
790 | |
791 | bool initcall_debug; |
792 | core_param(initcall_debug, initcall_debug, bool, 0644); |
793 | |
794 | #ifdef TRACEPOINTS_ENABLED |
795 | static void __init initcall_debug_enable(void); |
796 | #else |
797 | static inline void initcall_debug_enable(void) |
798 | { |
799 | } |
800 | #endif |
801 | |
802 | #ifdef CONFIG_RANDOMIZE_KSTACK_OFFSET |
803 | DEFINE_STATIC_KEY_MAYBE_RO(CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT, |
804 | randomize_kstack_offset); |
805 | DEFINE_PER_CPU(u32, kstack_offset); |
806 | |
807 | static int __init early_randomize_kstack_offset(char *buf) |
808 | { |
809 | int ret; |
810 | bool bool_result; |
811 | |
812 | ret = kstrtobool(s: buf, res: &bool_result); |
813 | if (ret) |
814 | return ret; |
815 | |
816 | if (bool_result) |
817 | static_branch_enable(&randomize_kstack_offset); |
818 | else |
819 | static_branch_disable(&randomize_kstack_offset); |
820 | return 0; |
821 | } |
822 | early_param("randomize_kstack_offset" , early_randomize_kstack_offset); |
823 | #endif |
824 | |
825 | void __init __weak __noreturn arch_call_rest_init(void) |
826 | { |
827 | rest_init(); |
828 | } |
829 | |
830 | static void __init print_unknown_bootoptions(void) |
831 | { |
832 | char *unknown_options; |
833 | char *end; |
834 | const char *const *p; |
835 | size_t len; |
836 | |
837 | if (panic_later || (!argv_init[1] && !envp_init[2])) |
838 | return; |
839 | |
840 | /* |
841 | * Determine how many options we have to print out, plus a space |
842 | * before each |
843 | */ |
844 | len = 1; /* null terminator */ |
845 | for (p = &argv_init[1]; *p; p++) { |
846 | len++; |
847 | len += strlen(*p); |
848 | } |
849 | for (p = &envp_init[2]; *p; p++) { |
850 | len++; |
851 | len += strlen(*p); |
852 | } |
853 | |
854 | unknown_options = memblock_alloc(size: len, SMP_CACHE_BYTES); |
855 | if (!unknown_options) { |
856 | pr_err("%s: Failed to allocate %zu bytes\n" , |
857 | __func__, len); |
858 | return; |
859 | } |
860 | end = unknown_options; |
861 | |
862 | for (p = &argv_init[1]; *p; p++) |
863 | end += sprintf(buf: end, fmt: " %s" , *p); |
864 | for (p = &envp_init[2]; *p; p++) |
865 | end += sprintf(buf: end, fmt: " %s" , *p); |
866 | |
867 | /* Start at unknown_options[1] to skip the initial space */ |
868 | pr_notice("Unknown kernel command line parameters \"%s\", will be passed to user space.\n" , |
869 | &unknown_options[1]); |
870 | memblock_free(ptr: unknown_options, size: len); |
871 | } |
872 | |
873 | asmlinkage __visible __init __no_sanitize_address __noreturn __no_stack_protector |
874 | void start_kernel(void) |
875 | { |
876 | char *command_line; |
877 | char *after_dashes; |
878 | |
879 | set_task_stack_end_magic(&init_task); |
880 | smp_setup_processor_id(); |
881 | debug_objects_early_init(); |
882 | init_vmlinux_build_id(); |
883 | |
884 | cgroup_init_early(); |
885 | |
886 | local_irq_disable(); |
887 | early_boot_irqs_disabled = true; |
888 | |
889 | /* |
890 | * Interrupts are still disabled. Do necessary setups, then |
891 | * enable them. |
892 | */ |
893 | boot_cpu_init(); |
894 | page_address_init(); |
895 | pr_notice("%s" , linux_banner); |
896 | early_security_init(); |
897 | setup_arch(&command_line); |
898 | setup_boot_config(); |
899 | setup_command_line(command_line); |
900 | setup_nr_cpu_ids(); |
901 | setup_per_cpu_areas(); |
902 | smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */ |
903 | boot_cpu_hotplug_init(); |
904 | |
905 | pr_notice("Kernel command line: %s\n" , saved_command_line); |
906 | /* parameters may set static keys */ |
907 | jump_label_init(); |
908 | parse_early_param(); |
909 | after_dashes = parse_args(name: "Booting kernel" , |
910 | args: static_command_line, params: __start___param, |
911 | num: __stop___param - __start___param, |
912 | level_min: -1, level_max: -1, NULL, unknown: &unknown_bootoption); |
913 | print_unknown_bootoptions(); |
914 | if (!IS_ERR_OR_NULL(ptr: after_dashes)) |
915 | parse_args(name: "Setting init args" , args: after_dashes, NULL, num: 0, level_min: -1, level_max: -1, |
916 | NULL, unknown: set_init_arg); |
917 | if (extra_init_args) |
918 | parse_args(name: "Setting extra init args" , args: extra_init_args, |
919 | NULL, num: 0, level_min: -1, level_max: -1, NULL, unknown: set_init_arg); |
920 | |
921 | /* Architectural and non-timekeeping rng init, before allocator init */ |
922 | random_init_early(command_line); |
923 | |
924 | /* |
925 | * These use large bootmem allocations and must precede |
926 | * initalization of page allocator |
927 | */ |
928 | setup_log_buf(0); |
929 | vfs_caches_init_early(); |
930 | sort_main_extable(); |
931 | trap_init(); |
932 | mm_core_init(); |
933 | poking_init(); |
934 | ftrace_init(); |
935 | |
936 | /* trace_printk can be enabled here */ |
937 | early_trace_init(); |
938 | |
939 | /* |
940 | * Set up the scheduler prior starting any interrupts (such as the |
941 | * timer interrupt). Full topology setup happens at smp_init() |
942 | * time - but meanwhile we still have a functioning scheduler. |
943 | */ |
944 | sched_init(); |
945 | |
946 | if (WARN(!irqs_disabled(), |
947 | "Interrupts were enabled *very* early, fixing it\n" )) |
948 | local_irq_disable(); |
949 | radix_tree_init(); |
950 | maple_tree_init(); |
951 | |
952 | /* |
953 | * Set up housekeeping before setting up workqueues to allow the unbound |
954 | * workqueue to take non-housekeeping into account. |
955 | */ |
956 | housekeeping_init(); |
957 | |
958 | /* |
959 | * Allow workqueue creation and work item queueing/cancelling |
960 | * early. Work item execution depends on kthreads and starts after |
961 | * workqueue_init(). |
962 | */ |
963 | workqueue_init_early(); |
964 | |
965 | rcu_init(); |
966 | |
967 | /* Trace events are available after this */ |
968 | trace_init(); |
969 | |
970 | if (initcall_debug) |
971 | initcall_debug_enable(); |
972 | |
973 | context_tracking_init(); |
974 | /* init some links before init_ISA_irqs() */ |
975 | early_irq_init(); |
976 | init_IRQ(); |
977 | tick_init(); |
978 | rcu_init_nohz(); |
979 | init_timers(); |
980 | srcu_init(); |
981 | hrtimers_init(); |
982 | softirq_init(); |
983 | timekeeping_init(); |
984 | time_init(); |
985 | |
986 | /* This must be after timekeeping is initialized */ |
987 | random_init(); |
988 | |
989 | /* These make use of the fully initialized rng */ |
990 | kfence_init(); |
991 | boot_init_stack_canary(); |
992 | |
993 | perf_event_init(); |
994 | profile_init(); |
995 | call_function_init(); |
996 | WARN(!irqs_disabled(), "Interrupts were enabled early\n" ); |
997 | |
998 | early_boot_irqs_disabled = false; |
999 | local_irq_enable(); |
1000 | |
1001 | kmem_cache_init_late(); |
1002 | |
1003 | /* |
1004 | * HACK ALERT! This is early. We're enabling the console before |
1005 | * we've done PCI setups etc, and console_init() must be aware of |
1006 | * this. But we do want output early, in case something goes wrong. |
1007 | */ |
1008 | console_init(); |
1009 | if (panic_later) |
1010 | panic(fmt: "Too many boot %s vars at `%s'" , panic_later, |
1011 | panic_param); |
1012 | |
1013 | lockdep_init(); |
1014 | |
1015 | /* |
1016 | * Need to run this when irqs are enabled, because it wants |
1017 | * to self-test [hard/soft]-irqs on/off lock inversion bugs |
1018 | * too: |
1019 | */ |
1020 | locking_selftest(); |
1021 | |
1022 | #ifdef CONFIG_BLK_DEV_INITRD |
1023 | if (initrd_start && !initrd_below_start_ok && |
1024 | page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) { |
1025 | pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n" , |
1026 | page_to_pfn(virt_to_page((void *)initrd_start)), |
1027 | min_low_pfn); |
1028 | initrd_start = 0; |
1029 | } |
1030 | #endif |
1031 | setup_per_cpu_pageset(); |
1032 | numa_policy_init(); |
1033 | acpi_early_init(); |
1034 | if (late_time_init) |
1035 | late_time_init(); |
1036 | sched_clock_init(); |
1037 | calibrate_delay(); |
1038 | |
1039 | arch_cpu_finalize_init(); |
1040 | |
1041 | pid_idr_init(); |
1042 | anon_vma_init(); |
1043 | #ifdef CONFIG_X86 |
1044 | if (efi_enabled(EFI_RUNTIME_SERVICES)) |
1045 | efi_enter_virtual_mode(); |
1046 | #endif |
1047 | thread_stack_cache_init(); |
1048 | cred_init(); |
1049 | fork_init(); |
1050 | proc_caches_init(); |
1051 | uts_ns_init(); |
1052 | key_init(); |
1053 | security_init(); |
1054 | dbg_late_init(); |
1055 | net_ns_init(); |
1056 | vfs_caches_init(); |
1057 | pagecache_init(); |
1058 | signals_init(); |
1059 | seq_file_init(); |
1060 | proc_root_init(); |
1061 | nsfs_init(); |
1062 | cpuset_init(); |
1063 | cgroup_init(); |
1064 | taskstats_init_early(); |
1065 | delayacct_init(); |
1066 | |
1067 | acpi_subsystem_init(); |
1068 | arch_post_acpi_subsys_init(); |
1069 | kcsan_init(); |
1070 | |
1071 | /* Do the rest non-__init'ed, we're now alive */ |
1072 | arch_call_rest_init(); |
1073 | |
1074 | /* |
1075 | * Avoid stack canaries in callers of boot_init_stack_canary for gcc-10 |
1076 | * and older. |
1077 | */ |
1078 | #if !__has_attribute(__no_stack_protector__) |
1079 | prevent_tail_call_optimization(); |
1080 | #endif |
1081 | } |
1082 | |
1083 | /* Call all constructor functions linked into the kernel. */ |
1084 | static void __init do_ctors(void) |
1085 | { |
1086 | /* |
1087 | * For UML, the constructors have already been called by the |
1088 | * normal setup code as it's just a normal ELF binary, so we |
1089 | * cannot do it again - but we do need CONFIG_CONSTRUCTORS |
1090 | * even on UML for modules. |
1091 | */ |
1092 | #if defined(CONFIG_CONSTRUCTORS) && !defined(CONFIG_UML) |
1093 | ctor_fn_t *fn = (ctor_fn_t *) __ctors_start; |
1094 | |
1095 | for (; fn < (ctor_fn_t *) __ctors_end; fn++) |
1096 | (*fn)(); |
1097 | #endif |
1098 | } |
1099 | |
1100 | #ifdef CONFIG_KALLSYMS |
1101 | struct blacklist_entry { |
1102 | struct list_head next; |
1103 | char *buf; |
1104 | }; |
1105 | |
1106 | static __initdata_or_module LIST_HEAD(blacklisted_initcalls); |
1107 | |
1108 | static int __init initcall_blacklist(char *str) |
1109 | { |
1110 | char *str_entry; |
1111 | struct blacklist_entry *entry; |
1112 | |
1113 | /* str argument is a comma-separated list of functions */ |
1114 | do { |
1115 | str_entry = strsep(&str, "," ); |
1116 | if (str_entry) { |
1117 | pr_debug("blacklisting initcall %s\n" , str_entry); |
1118 | entry = memblock_alloc(size: sizeof(*entry), |
1119 | SMP_CACHE_BYTES); |
1120 | if (!entry) |
1121 | panic(fmt: "%s: Failed to allocate %zu bytes\n" , |
1122 | __func__, sizeof(*entry)); |
1123 | entry->buf = memblock_alloc(strlen(str_entry) + 1, |
1124 | SMP_CACHE_BYTES); |
1125 | if (!entry->buf) |
1126 | panic(fmt: "%s: Failed to allocate %zu bytes\n" , |
1127 | __func__, strlen(str_entry) + 1); |
1128 | strcpy(p: entry->buf, q: str_entry); |
1129 | list_add(new: &entry->next, head: &blacklisted_initcalls); |
1130 | } |
1131 | } while (str_entry); |
1132 | |
1133 | return 1; |
1134 | } |
1135 | |
1136 | static bool __init_or_module initcall_blacklisted(initcall_t fn) |
1137 | { |
1138 | struct blacklist_entry *entry; |
1139 | char fn_name[KSYM_SYMBOL_LEN]; |
1140 | unsigned long addr; |
1141 | |
1142 | if (list_empty(head: &blacklisted_initcalls)) |
1143 | return false; |
1144 | |
1145 | addr = (unsigned long) dereference_function_descriptor(fn); |
1146 | sprint_symbol_no_offset(buffer: fn_name, address: addr); |
1147 | |
1148 | /* |
1149 | * fn will be "function_name [module_name]" where [module_name] is not |
1150 | * displayed for built-in init functions. Strip off the [module_name]. |
1151 | */ |
1152 | strreplace(str: fn_name, old: ' ', new: '\0'); |
1153 | |
1154 | list_for_each_entry(entry, &blacklisted_initcalls, next) { |
1155 | if (!strcmp(fn_name, entry->buf)) { |
1156 | pr_debug("initcall %s blacklisted\n" , fn_name); |
1157 | return true; |
1158 | } |
1159 | } |
1160 | |
1161 | return false; |
1162 | } |
1163 | #else |
1164 | static int __init initcall_blacklist(char *str) |
1165 | { |
1166 | pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n" ); |
1167 | return 0; |
1168 | } |
1169 | |
1170 | static bool __init_or_module initcall_blacklisted(initcall_t fn) |
1171 | { |
1172 | return false; |
1173 | } |
1174 | #endif |
1175 | __setup("initcall_blacklist=" , initcall_blacklist); |
1176 | |
1177 | static __init_or_module void |
1178 | trace_initcall_start_cb(void *data, initcall_t fn) |
1179 | { |
1180 | ktime_t *calltime = data; |
1181 | |
1182 | printk(KERN_DEBUG "calling %pS @ %i\n" , fn, task_pid_nr(current)); |
1183 | *calltime = ktime_get(); |
1184 | } |
1185 | |
1186 | static __init_or_module void |
1187 | trace_initcall_finish_cb(void *data, initcall_t fn, int ret) |
1188 | { |
1189 | ktime_t rettime, *calltime = data; |
1190 | |
1191 | rettime = ktime_get(); |
1192 | printk(KERN_DEBUG "initcall %pS returned %d after %lld usecs\n" , |
1193 | fn, ret, (unsigned long long)ktime_us_delta(rettime, *calltime)); |
1194 | } |
1195 | |
1196 | static ktime_t initcall_calltime; |
1197 | |
1198 | #ifdef TRACEPOINTS_ENABLED |
1199 | static void __init initcall_debug_enable(void) |
1200 | { |
1201 | int ret; |
1202 | |
1203 | ret = register_trace_initcall_start(probe: trace_initcall_start_cb, |
1204 | data: &initcall_calltime); |
1205 | ret |= register_trace_initcall_finish(probe: trace_initcall_finish_cb, |
1206 | data: &initcall_calltime); |
1207 | WARN(ret, "Failed to register initcall tracepoints\n" ); |
1208 | } |
1209 | # define do_trace_initcall_start trace_initcall_start |
1210 | # define do_trace_initcall_finish trace_initcall_finish |
1211 | #else |
1212 | static inline void do_trace_initcall_start(initcall_t fn) |
1213 | { |
1214 | if (!initcall_debug) |
1215 | return; |
1216 | trace_initcall_start_cb(&initcall_calltime, fn); |
1217 | } |
1218 | static inline void do_trace_initcall_finish(initcall_t fn, int ret) |
1219 | { |
1220 | if (!initcall_debug) |
1221 | return; |
1222 | trace_initcall_finish_cb(&initcall_calltime, fn, ret); |
1223 | } |
1224 | #endif /* !TRACEPOINTS_ENABLED */ |
1225 | |
1226 | int __init_or_module do_one_initcall(initcall_t fn) |
1227 | { |
1228 | int count = preempt_count(); |
1229 | char msgbuf[64]; |
1230 | int ret; |
1231 | |
1232 | if (initcall_blacklisted(fn)) |
1233 | return -EPERM; |
1234 | |
1235 | do_trace_initcall_start(func: fn); |
1236 | ret = fn(); |
1237 | do_trace_initcall_finish(func: fn, ret); |
1238 | |
1239 | msgbuf[0] = 0; |
1240 | |
1241 | if (preempt_count() != count) { |
1242 | sprintf(buf: msgbuf, fmt: "preemption imbalance " ); |
1243 | preempt_count_set(pc: count); |
1244 | } |
1245 | if (irqs_disabled()) { |
1246 | strlcat(p: msgbuf, q: "disabled interrupts " , avail: sizeof(msgbuf)); |
1247 | local_irq_enable(); |
1248 | } |
1249 | WARN(msgbuf[0], "initcall %pS returned with %s\n" , fn, msgbuf); |
1250 | |
1251 | add_latent_entropy(); |
1252 | return ret; |
1253 | } |
1254 | |
1255 | |
1256 | static initcall_entry_t *initcall_levels[] __initdata = { |
1257 | __initcall0_start, |
1258 | __initcall1_start, |
1259 | __initcall2_start, |
1260 | __initcall3_start, |
1261 | __initcall4_start, |
1262 | __initcall5_start, |
1263 | __initcall6_start, |
1264 | __initcall7_start, |
1265 | __initcall_end, |
1266 | }; |
1267 | |
1268 | /* Keep these in sync with initcalls in include/linux/init.h */ |
1269 | static const char *initcall_level_names[] __initdata = { |
1270 | "pure" , |
1271 | "core" , |
1272 | "postcore" , |
1273 | "arch" , |
1274 | "subsys" , |
1275 | "fs" , |
1276 | "device" , |
1277 | "late" , |
1278 | }; |
1279 | |
1280 | static int __init ignore_unknown_bootoption(char *param, char *val, |
1281 | const char *unused, void *arg) |
1282 | { |
1283 | return 0; |
1284 | } |
1285 | |
1286 | static void __init do_initcall_level(int level, char *command_line) |
1287 | { |
1288 | initcall_entry_t *fn; |
1289 | |
1290 | parse_args(name: initcall_level_names[level], |
1291 | args: command_line, params: __start___param, |
1292 | num: __stop___param - __start___param, |
1293 | level_min: level, level_max: level, |
1294 | NULL, unknown: ignore_unknown_bootoption); |
1295 | |
1296 | trace_initcall_level(level: initcall_level_names[level]); |
1297 | for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++) |
1298 | do_one_initcall(fn: initcall_from_entry(entry: fn)); |
1299 | } |
1300 | |
1301 | static void __init do_initcalls(void) |
1302 | { |
1303 | int level; |
1304 | size_t len = saved_command_line_len + 1; |
1305 | char *command_line; |
1306 | |
1307 | command_line = kzalloc(size: len, GFP_KERNEL); |
1308 | if (!command_line) |
1309 | panic(fmt: "%s: Failed to allocate %zu bytes\n" , __func__, len); |
1310 | |
1311 | for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) { |
1312 | /* Parser modifies command_line, restore it each time */ |
1313 | strcpy(p: command_line, q: saved_command_line); |
1314 | do_initcall_level(level, command_line); |
1315 | } |
1316 | |
1317 | kfree(objp: command_line); |
1318 | } |
1319 | |
1320 | /* |
1321 | * Ok, the machine is now initialized. None of the devices |
1322 | * have been touched yet, but the CPU subsystem is up and |
1323 | * running, and memory and process management works. |
1324 | * |
1325 | * Now we can finally start doing some real work.. |
1326 | */ |
1327 | static void __init do_basic_setup(void) |
1328 | { |
1329 | cpuset_init_smp(); |
1330 | driver_init(); |
1331 | init_irq_proc(); |
1332 | do_ctors(); |
1333 | do_initcalls(); |
1334 | } |
1335 | |
1336 | static void __init do_pre_smp_initcalls(void) |
1337 | { |
1338 | initcall_entry_t *fn; |
1339 | |
1340 | trace_initcall_level(level: "early" ); |
1341 | for (fn = __initcall_start; fn < __initcall0_start; fn++) |
1342 | do_one_initcall(fn: initcall_from_entry(entry: fn)); |
1343 | } |
1344 | |
1345 | static int run_init_process(const char *init_filename) |
1346 | { |
1347 | const char *const *p; |
1348 | |
1349 | argv_init[0] = init_filename; |
1350 | pr_info("Run %s as init process\n" , init_filename); |
1351 | pr_debug(" with arguments:\n" ); |
1352 | for (p = argv_init; *p; p++) |
1353 | pr_debug(" %s\n" , *p); |
1354 | pr_debug(" with environment:\n" ); |
1355 | for (p = envp_init; *p; p++) |
1356 | pr_debug(" %s\n" , *p); |
1357 | return kernel_execve(filename: init_filename, argv: argv_init, envp: envp_init); |
1358 | } |
1359 | |
1360 | static int try_to_run_init_process(const char *init_filename) |
1361 | { |
1362 | int ret; |
1363 | |
1364 | ret = run_init_process(init_filename); |
1365 | |
1366 | if (ret && ret != -ENOENT) { |
1367 | pr_err("Starting init: %s exists but couldn't execute it (error %d)\n" , |
1368 | init_filename, ret); |
1369 | } |
1370 | |
1371 | return ret; |
1372 | } |
1373 | |
1374 | static noinline void __init kernel_init_freeable(void); |
1375 | |
1376 | #if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX) |
1377 | bool rodata_enabled __ro_after_init = true; |
1378 | |
1379 | #ifndef arch_parse_debug_rodata |
1380 | static inline bool arch_parse_debug_rodata(char *str) { return false; } |
1381 | #endif |
1382 | |
1383 | static int __init set_debug_rodata(char *str) |
1384 | { |
1385 | if (arch_parse_debug_rodata(str)) |
1386 | return 0; |
1387 | |
1388 | if (str && !strcmp(str, "on" )) |
1389 | rodata_enabled = true; |
1390 | else if (str && !strcmp(str, "off" )) |
1391 | rodata_enabled = false; |
1392 | else |
1393 | pr_warn("Invalid option string for rodata: '%s'\n" , str); |
1394 | return 0; |
1395 | } |
1396 | early_param("rodata" , set_debug_rodata); |
1397 | #endif |
1398 | |
1399 | #ifdef CONFIG_STRICT_KERNEL_RWX |
1400 | static void mark_readonly(void) |
1401 | { |
1402 | if (rodata_enabled) { |
1403 | /* |
1404 | * load_module() results in W+X mappings, which are cleaned |
1405 | * up with call_rcu(). Let's make sure that queued work is |
1406 | * flushed so that we don't hit false positives looking for |
1407 | * insecure pages which are W+X. |
1408 | */ |
1409 | rcu_barrier(); |
1410 | mark_rodata_ro(); |
1411 | rodata_test(); |
1412 | } else |
1413 | pr_info("Kernel memory protection disabled.\n" ); |
1414 | } |
1415 | #elif defined(CONFIG_ARCH_HAS_STRICT_KERNEL_RWX) |
1416 | static inline void mark_readonly(void) |
1417 | { |
1418 | pr_warn("Kernel memory protection not selected by kernel config.\n" ); |
1419 | } |
1420 | #else |
1421 | static inline void mark_readonly(void) |
1422 | { |
1423 | pr_warn("This architecture does not have kernel memory protection.\n" ); |
1424 | } |
1425 | #endif |
1426 | |
1427 | void __weak free_initmem(void) |
1428 | { |
1429 | free_initmem_default(POISON_FREE_INITMEM); |
1430 | } |
1431 | |
1432 | static int __ref kernel_init(void *unused) |
1433 | { |
1434 | int ret; |
1435 | |
1436 | /* |
1437 | * Wait until kthreadd is all set-up. |
1438 | */ |
1439 | wait_for_completion(&kthreadd_done); |
1440 | |
1441 | kernel_init_freeable(); |
1442 | /* need to finish all async __init code before freeing the memory */ |
1443 | async_synchronize_full(); |
1444 | |
1445 | system_state = SYSTEM_FREEING_INITMEM; |
1446 | kprobe_free_init_mem(); |
1447 | ftrace_free_init_mem(); |
1448 | kgdb_free_init_mem(); |
1449 | exit_boot_config(); |
1450 | free_initmem(); |
1451 | mark_readonly(); |
1452 | |
1453 | /* |
1454 | * Kernel mappings are now finalized - update the userspace page-table |
1455 | * to finalize PTI. |
1456 | */ |
1457 | pti_finalize(); |
1458 | |
1459 | system_state = SYSTEM_RUNNING; |
1460 | numa_default_policy(); |
1461 | |
1462 | rcu_end_inkernel_boot(); |
1463 | |
1464 | do_sysctl_args(); |
1465 | |
1466 | if (ramdisk_execute_command) { |
1467 | ret = run_init_process(init_filename: ramdisk_execute_command); |
1468 | if (!ret) |
1469 | return 0; |
1470 | pr_err("Failed to execute %s (error %d)\n" , |
1471 | ramdisk_execute_command, ret); |
1472 | } |
1473 | |
1474 | /* |
1475 | * We try each of these until one succeeds. |
1476 | * |
1477 | * The Bourne shell can be used instead of init if we are |
1478 | * trying to recover a really broken machine. |
1479 | */ |
1480 | if (execute_command) { |
1481 | ret = run_init_process(init_filename: execute_command); |
1482 | if (!ret) |
1483 | return 0; |
1484 | panic(fmt: "Requested init %s failed (error %d)." , |
1485 | execute_command, ret); |
1486 | } |
1487 | |
1488 | if (CONFIG_DEFAULT_INIT[0] != '\0') { |
1489 | ret = run_init_process(CONFIG_DEFAULT_INIT); |
1490 | if (ret) |
1491 | pr_err("Default init %s failed (error %d)\n" , |
1492 | CONFIG_DEFAULT_INIT, ret); |
1493 | else |
1494 | return 0; |
1495 | } |
1496 | |
1497 | if (!try_to_run_init_process(init_filename: "/sbin/init" ) || |
1498 | !try_to_run_init_process(init_filename: "/etc/init" ) || |
1499 | !try_to_run_init_process(init_filename: "/bin/init" ) || |
1500 | !try_to_run_init_process(init_filename: "/bin/sh" )) |
1501 | return 0; |
1502 | |
1503 | panic(fmt: "No working init found. Try passing init= option to kernel. " |
1504 | "See Linux Documentation/admin-guide/init.rst for guidance." ); |
1505 | } |
1506 | |
1507 | /* Open /dev/console, for stdin/stdout/stderr, this should never fail */ |
1508 | void __init console_on_rootfs(void) |
1509 | { |
1510 | struct file *file = filp_open("/dev/console" , O_RDWR, 0); |
1511 | |
1512 | if (IS_ERR(ptr: file)) { |
1513 | pr_err("Warning: unable to open an initial console.\n" ); |
1514 | return; |
1515 | } |
1516 | init_dup(file); |
1517 | init_dup(file); |
1518 | init_dup(file); |
1519 | fput(file); |
1520 | } |
1521 | |
1522 | static noinline void __init kernel_init_freeable(void) |
1523 | { |
1524 | /* Now the scheduler is fully set up and can do blocking allocations */ |
1525 | gfp_allowed_mask = __GFP_BITS_MASK; |
1526 | |
1527 | /* |
1528 | * init can allocate pages on any node |
1529 | */ |
1530 | set_mems_allowed(node_states[N_MEMORY]); |
1531 | |
1532 | cad_pid = get_pid(pid: task_pid(current)); |
1533 | |
1534 | smp_prepare_cpus(max_cpus: setup_max_cpus); |
1535 | |
1536 | workqueue_init(); |
1537 | |
1538 | init_mm_internals(); |
1539 | |
1540 | rcu_init_tasks_generic(); |
1541 | do_pre_smp_initcalls(); |
1542 | lockup_detector_init(); |
1543 | |
1544 | smp_init(); |
1545 | sched_init_smp(); |
1546 | |
1547 | workqueue_init_topology(); |
1548 | padata_init(); |
1549 | page_alloc_init_late(); |
1550 | |
1551 | do_basic_setup(); |
1552 | |
1553 | kunit_run_all_tests(); |
1554 | |
1555 | wait_for_initramfs(); |
1556 | console_on_rootfs(); |
1557 | |
1558 | /* |
1559 | * check if there is an early userspace init. If yes, let it do all |
1560 | * the work |
1561 | */ |
1562 | if (init_eaccess(filename: ramdisk_execute_command) != 0) { |
1563 | ramdisk_execute_command = NULL; |
1564 | prepare_namespace(); |
1565 | } |
1566 | |
1567 | /* |
1568 | * Ok, we have completed the initial bootup, and |
1569 | * we're essentially up and running. Get rid of the |
1570 | * initmem segments and start the user-mode stuff.. |
1571 | * |
1572 | * rootfs is available now, try loading the public keys |
1573 | * and default modules |
1574 | */ |
1575 | |
1576 | integrity_load_keys(); |
1577 | } |
1578 | |