blob: 4a6974e678396d73189f4629537475bc9f3aee42 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/init/main.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 *
6 * GK 2/5/95 - Changed to support mounting root fs via NFS
7 * Added initrd & change_root: Werner Almesberger & Hans Lermen, Feb '96
8 * Moan early if gcc is old, avoiding bogus kernels - Paul Gortmaker, May '96
Fabian Frederickdd4d9fe2014-08-08 14:23:44 -07009 * Simplified starting of init: Michael A. Griffith <grif@acm.org>
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 */
11
Andrew Mortonea676e82013-04-29 16:18:20 -070012#define DEBUG /* Enable initcall_debug */
13
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <linux/types.h>
15#include <linux/module.h>
16#include <linux/proc_fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/kernel.h>
18#include <linux/syscalls.h>
Ingo Molnar9b5609f2008-02-14 09:41:09 +010019#include <linux/stackprotector.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/string.h>
21#include <linux/ctype.h>
22#include <linux/delay.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/ioport.h>
24#include <linux/init.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070025#include <linux/initrd.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <linux/bootmem.h>
Len Brown4a7a16d2009-06-12 20:42:08 -040027#include <linux/acpi.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include <linux/tty.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#include <linux/percpu.h>
30#include <linux/kmod.h>
Nick Piggindb64fe02008-10-18 20:27:03 -070031#include <linux/vmalloc.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070032#include <linux/kernel_stat.h>
Rusty Russelld7cd5612006-12-07 02:14:08 +010033#include <linux/start_kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <linux/security.h>
Jens Axboe3d442232008-06-26 11:21:34 +020035#include <linux/smp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070036#include <linux/profile.h>
37#include <linux/rcupdate.h>
38#include <linux/moduleparam.h>
39#include <linux/kallsyms.h>
40#include <linux/writeback.h>
41#include <linux/cpu.h>
42#include <linux/cpuset.h>
Paul Menageddbcc7e2007-10-18 23:39:30 -070043#include <linux/cgroup.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070044#include <linux/efi.h>
Thomas Gleixner906568c2007-02-16 01:28:01 -080045#include <linux/tick.h>
Andrew Morton6168a702007-02-17 21:22:39 -080046#include <linux/interrupt.h>
Shailabh Nagarc7572492006-07-14 00:24:40 -070047#include <linux/taskstats_kern.h>
Shailabh Nagarca74e922006-07-14 00:24:36 -070048#include <linux/delayacct.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070049#include <linux/unistd.h>
50#include <linux/rmap.h>
51#include <linux/mempolicy.h>
52#include <linux/key.h>
Adrian Bunkb6cd0b72006-06-27 02:53:54 -070053#include <linux/buffer_head.h>
Joonsoo Kimeefa864b2014-12-12 16:55:46 -080054#include <linux/page_ext.h>
Ingo Molnar9a11b49a2006-07-03 00:24:33 -070055#include <linux/debug_locks.h>
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -070056#include <linux/debugobjects.h>
Ingo Molnarfbb9ce952006-07-03 00:24:50 -070057#include <linux/lockdep.h>
Catalin Marinas3c7b4e62009-06-11 13:22:39 +010058#include <linux/kmemleak.h>
Sukadev Bhattiprolu84d73782006-12-08 02:38:01 -080059#include <linux/pid_namespace.h>
Adrian Bunk1f217822006-12-19 13:01:28 -080060#include <linux/device.h>
Eric W. Biederman73c27992007-05-09 02:34:32 -070061#include <linux/kthread.h>
Adrian Bunke6fe6642007-11-09 22:39:39 +010062#include <linux/sched.h>
Adrian Bunka1c9eea2008-02-06 01:36:44 -080063#include <linux/signal.h>
Akinobu Mita199f0ca2008-04-29 01:03:13 -070064#include <linux/idr.h>
Jason Wessel0b4b3822010-05-20 21:04:29 -050065#include <linux/kgdb.h>
Steven Rostedt68bf21a2008-08-14 15:45:08 -040066#include <linux/ftrace.h>
Arjan van de Ven22a9d642009-01-07 08:45:46 -080067#include <linux/async.h>
Vegard Nossumdfec0722008-04-04 00:51:41 +020068#include <linux/kmemcheck.h>
Feng Tang6ae69962009-08-14 15:13:46 -040069#include <linux/sfi.h>
Kay Sievers2b2af542009-04-30 15:23:42 +020070#include <linux/shmem_fs.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090071#include <linux/slab.h>
Peter Zijlstra24a24bb2010-11-17 23:17:33 +010072#include <linux/perf_event.h>
Al Viro4a9d4b02012-06-24 09:56:45 +040073#include <linux/file.h>
Al Viroa74fb732012-10-10 21:28:25 -040074#include <linux/ptrace.h>
Tejun Heobb813f42013-01-18 14:05:56 -080075#include <linux/blkdev.h>
76#include <linux/elevator.h>
Stephen Boyd38ff87f2013-06-01 23:39:40 -070077#include <linux/sched_clock.h>
Frederic Weisbecker65f382f2013-07-11 19:12:32 +020078#include <linux/context_tracking.h>
Theodore Ts'o47d06e52013-09-10 10:52:35 -040079#include <linux/random.h>
Prarit Bhargava7b0b73d2014-06-04 16:12:17 -070080#include <linux/list.h>
Dmitry Kasatkinc9cd2ce2014-11-05 17:01:15 +020081#include <linux/integrity.h>
Al Viroe149ed22014-11-01 10:57:28 -040082#include <linux/proc_ns.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070083
84#include <asm/io.h>
85#include <asm/bugs.h>
86#include <asm/setup.h>
Andi Kleena9401992005-07-28 21:15:30 -070087#include <asm/sections.h>
Arjan van de Ven37b73c82006-01-06 00:12:01 -080088#include <asm/cacheflush.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070089
Sam Ravnborgaae5f662007-02-26 16:45:41 +010090static int kernel_init(void *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070091
92extern void init_IRQ(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070093extern void fork_init(unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -070094extern void radix_tree_init(void);
Arjan van de Ven37b73c82006-01-06 00:12:01 -080095#ifndef CONFIG_DEBUG_RODATA
96static inline void mark_rodata_ro(void) { }
97#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070098
Tejun Heo2ce802f2011-01-20 12:06:35 +010099/*
100 * Debug helper: via this flag we know that we are in 'early bootup code'
101 * where only the boot processor is running with IRQ disabled. This means
102 * two things - IRQ must not be enabled before the flag is cleared and some
103 * operations which are not allowed with IRQ disabled are allowed while the
104 * flag is set.
105 */
106bool early_boot_irqs_disabled __read_mostly;
107
Paul E. McKenneya6826042009-02-25 18:03:42 -0800108enum system_states system_state __read_mostly;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109EXPORT_SYMBOL(system_state);
110
111/*
112 * Boot command-line arguments
113 */
114#define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
115#define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
116
117extern void time_init(void);
118/* Default late time init is NULL. archs can override this later. */
Jan Beulichd2e31922009-01-06 14:41:10 -0800119void (*__initdata late_time_init)(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800121/* Untouched command line saved by arch-specific code. */
122char __initdata boot_command_line[COMMAND_LINE_SIZE];
123/* Untouched saved command line (eg. for /proc) */
124char *saved_command_line;
125/* Command line for parameter parsing */
126static char *static_command_line;
Krzysztof Mazur08746a62013-10-31 13:45:39 +1030127/* Command line for per-initcall parameter parsing */
128static char *initcall_command_line;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129
130static char *execute_command;
Olof Johanssonffdfc402005-09-06 15:17:19 -0700131static char *ramdisk_execute_command;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132
Jan Beulich8b3b2952007-07-15 23:41:07 -0700133/*
Hannes Frederic Sowac4b2c0c2013-10-19 21:48:53 +0200134 * Used to generate warnings if static_key manipulation functions are used
135 * before jump_label_init is called.
136 */
Fabian Frederickdd4d9fe2014-08-08 14:23:44 -0700137bool static_key_initialized __read_mostly;
Hannes Frederic Sowac4b2c0c2013-10-19 21:48:53 +0200138EXPORT_SYMBOL_GPL(static_key_initialized);
139
140/*
Jan Beulich8b3b2952007-07-15 23:41:07 -0700141 * If set, this is an indication to the drivers that reset the underlying
142 * device before going ahead with the initialization otherwise driver might
143 * rely on the BIOS and skip the reset operation.
144 *
145 * This is useful if kernel is booting in an unreliable environment.
146 * For ex. kdump situaiton where previous kernel has crashed, BIOS has been
147 * skipped and devices will be in unknown state.
148 */
149unsigned int reset_devices;
150EXPORT_SYMBOL(reset_devices);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151
Vivek Goyal7e962872006-09-27 01:50:44 -0700152static int __init set_reset_devices(char *str)
153{
154 reset_devices = 1;
155 return 1;
156}
157
158__setup("reset_devices", set_reset_devices);
159
Fabian Frederickdd4d9fe2014-08-08 14:23:44 -0700160static const char *argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
161const char *envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162static const char *panic_later, *panic_param;
163
Rusty Russell914dcaa2010-08-11 23:04:18 -0600164extern const struct obs_kernel_param __setup_start[], __setup_end[];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165
166static int __init obsolete_checksetup(char *line)
167{
Rusty Russell914dcaa2010-08-11 23:04:18 -0600168 const struct obs_kernel_param *p;
Rusty Russell33df0d12006-09-26 10:52:32 +0200169 int had_early_param = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170
171 p = __setup_start;
172 do {
173 int n = strlen(p->str);
Michal Schmidtb1e4d202011-10-10 00:03:37 +0200174 if (parameqn(line, p->str, n)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 if (p->early) {
Rusty Russell33df0d12006-09-26 10:52:32 +0200176 /* Already done in parse_early_param?
177 * (Needs exact match on param part).
178 * Keep iterating, as we can have early
179 * params and __setups of same names 8( */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 if (line[n] == '\0' || line[n] == '=')
Rusty Russell33df0d12006-09-26 10:52:32 +0200181 had_early_param = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182 } else if (!p->setup_func) {
Andrew Mortonea676e82013-04-29 16:18:20 -0700183 pr_warn("Parameter %s is obsolete, ignored\n",
184 p->str);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 return 1;
186 } else if (p->setup_func(line + n))
187 return 1;
188 }
189 p++;
190 } while (p < __setup_end);
Rusty Russell33df0d12006-09-26 10:52:32 +0200191
192 return had_early_param;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193}
194
195/*
196 * This should be approx 2 Bo*oMips to start (note initial shift), and will
197 * still work even if initially too large, it will just take slightly longer
198 */
199unsigned long loops_per_jiffy = (1<<12);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200EXPORT_SYMBOL(loops_per_jiffy);
201
202static int __init debug_kernel(char *str)
203{
Borislav Petkova8fe19e2014-06-04 16:11:46 -0700204 console_loglevel = CONSOLE_LOGLEVEL_DEBUG;
Yinghai Luf6f21c812008-02-08 04:21:58 -0800205 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206}
207
208static int __init quiet_kernel(char *str)
209{
Borislav Petkova8fe19e2014-06-04 16:11:46 -0700210 console_loglevel = CONSOLE_LOGLEVEL_QUIET;
Yinghai Luf6f21c812008-02-08 04:21:58 -0800211 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212}
213
Yinghai Luf6f21c812008-02-08 04:21:58 -0800214early_param("debug", debug_kernel);
215early_param("quiet", quiet_kernel);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216
217static int __init loglevel(char *str)
218{
Alexander Sverdlin808bf292011-09-21 09:51:40 +0200219 int newlevel;
220
221 /*
222 * Only update loglevel value when a correct setting was passed,
223 * to prevent blind crashes (when loglevel being set to 0) that
224 * are quite hard to debug
225 */
226 if (get_option(&str, &newlevel)) {
227 console_loglevel = newlevel;
228 return 0;
229 }
230
231 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232}
233
Yinghai Luf6f21c812008-02-08 04:21:58 -0800234early_param("loglevel", loglevel);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235
Chris Metcalfa99cd112012-04-06 12:53:50 -0400236/* Change NUL term back to "=", to make "param" the whole string. */
Greg Kroah-Hartmaneb157422012-05-02 14:33:37 -0700237static int __init repair_env_string(char *param, char *val, const char *unused)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 if (val) {
240 /* param=val or param="val"? */
241 if (val == param+strlen(param)+1)
242 val[-1] = '=';
243 else if (val == param+strlen(param)+2) {
244 val[-2] = '=';
245 memmove(val-1, val, strlen(val)+1);
246 val--;
247 } else
248 BUG();
249 }
Chris Metcalfa99cd112012-04-06 12:53:50 -0400250 return 0;
251}
252
Rusty Russell51e158c2014-04-28 11:34:33 +0930253/* Anything after -- gets handed straight to init. */
254static int __init set_init_arg(char *param, char *val, const char *unused)
255{
256 unsigned int i;
257
258 if (panic_later)
259 return 0;
260
261 repair_env_string(param, val, unused);
262
263 for (i = 0; argv_init[i]; i++) {
264 if (i == MAX_INIT_ARGS) {
265 panic_later = "init";
266 panic_param = param;
267 return 0;
268 }
269 }
270 argv_init[i] = param;
271 return 0;
272}
273
Chris Metcalfa99cd112012-04-06 12:53:50 -0400274/*
275 * Unknown boot options get handed to init, unless they look like
276 * unused parameters (modprobe will find them in /proc/cmdline).
277 */
Greg Kroah-Hartmaneb157422012-05-02 14:33:37 -0700278static int __init unknown_bootoption(char *param, char *val, const char *unused)
Chris Metcalfa99cd112012-04-06 12:53:50 -0400279{
Greg Kroah-Hartmaneb157422012-05-02 14:33:37 -0700280 repair_env_string(param, val, unused);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281
282 /* Handle obsolete-style parameters */
283 if (obsolete_checksetup(param))
284 return 0;
285
Rusty Russellf066a4f2009-12-01 14:56:44 +1030286 /* Unused module parameter. */
287 if (strchr(param, '.') && (!val || strchr(param, '.') < val))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289
290 if (panic_later)
291 return 0;
292
293 if (val) {
294 /* Environment option */
295 unsigned int i;
296 for (i = 0; envp_init[i]; i++) {
297 if (i == MAX_INIT_ENVS) {
Tetsuo Handa499a4582014-01-23 15:54:56 -0800298 panic_later = "env";
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 panic_param = param;
300 }
301 if (!strncmp(param, envp_init[i], val - param))
302 break;
303 }
304 envp_init[i] = param;
305 } else {
306 /* Command line option */
307 unsigned int i;
308 for (i = 0; argv_init[i]; i++) {
309 if (i == MAX_INIT_ARGS) {
Tetsuo Handa499a4582014-01-23 15:54:56 -0800310 panic_later = "init";
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311 panic_param = param;
312 }
313 }
314 argv_init[i] = param;
315 }
316 return 0;
317}
318
319static int __init init_setup(char *str)
320{
321 unsigned int i;
322
323 execute_command = str;
324 /*
325 * In case LILO is going to boot us with default command line,
326 * it prepends "auto" before the whole cmdline which makes
327 * the shell think it should execute a script with such name.
328 * So we ignore all arguments entered _before_ init=... [MJ]
329 */
330 for (i = 1; i < MAX_INIT_ARGS; i++)
331 argv_init[i] = NULL;
332 return 1;
333}
334__setup("init=", init_setup);
335
Olof Johanssonffdfc402005-09-06 15:17:19 -0700336static int __init rdinit_setup(char *str)
337{
338 unsigned int i;
339
340 ramdisk_execute_command = str;
341 /* See "auto" comment in init_setup */
342 for (i = 1; i < MAX_INIT_ARGS; i++)
343 argv_init[i] = NULL;
344 return 1;
345}
346__setup("rdinit=", rdinit_setup);
347
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348#ifndef CONFIG_SMP
Amerigo Wang34db18a02011-03-22 16:34:06 -0700349static const unsigned int setup_max_cpus = NR_CPUS;
Mike Travise0982e92008-03-26 14:23:48 -0700350static inline void setup_nr_cpu_ids(void) { }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351static inline void smp_prepare_cpus(unsigned int maxcpus) { }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352#endif
353
354/*
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800355 * We need to store the untouched command line for future reference.
356 * We also need to store the touched command line since the parameter
357 * parsing is performed in place, and we should allow a component to
358 * store reference of name/value for future reference.
359 */
360static void __init setup_command_line(char *command_line)
361{
Santosh Shilimkar098b0812014-01-21 15:50:21 -0800362 saved_command_line =
363 memblock_virt_alloc(strlen(boot_command_line) + 1, 0);
364 initcall_command_line =
365 memblock_virt_alloc(strlen(boot_command_line) + 1, 0);
366 static_command_line = memblock_virt_alloc(strlen(command_line) + 1, 0);
Fabian Frederickdd4d9fe2014-08-08 14:23:44 -0700367 strcpy(saved_command_line, boot_command_line);
368 strcpy(static_command_line, command_line);
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800369}
370
371/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372 * We need to finalize in a non-__init function or else race conditions
373 * between the root thread and the init thread may cause start_kernel to
374 * be reaped by free_initmem before the root thread has proceeded to
375 * cpu_idle.
376 *
377 * gcc-3.4 accidentally inlines this function, so use noinline.
378 */
379
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200380static __initdata DECLARE_COMPLETION(kthreadd_done);
381
Rakib Mullickf99ebf02009-01-06 14:40:38 -0800382static noinline void __init_refok rest_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383{
Eric W. Biederman73c27992007-05-09 02:34:32 -0700384 int pid;
385
Paul E. McKenney7db905e2009-09-02 14:01:24 -0700386 rcu_scheduler_starting();
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200387 /*
Peter Zijlstra97158562010-06-30 10:37:11 +0200388 * We need to spawn init first so that it obtains pid 1, however
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200389 * the init task will end up wanting to create kthreads, which, if
390 * we schedule it before we create kthreadd, will OOPS.
391 */
Oleg Nesterov34a1b722014-06-04 16:12:19 -0700392 kernel_thread(kernel_init, NULL, CLONE_FS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 numa_default_policy();
Eric W. Biederman73c27992007-05-09 02:34:32 -0700394 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
Paul E. McKenneyd11c5632010-02-22 17:04:50 -0800395 rcu_read_lock();
Pavel Emelyanov5cd20452008-04-30 00:54:24 -0700396 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
Paul E. McKenneyd11c5632010-02-22 17:04:50 -0800397 rcu_read_unlock();
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200398 complete(&kthreadd_done);
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200399
400 /*
401 * The boot idle thread must execute schedule()
Ingo Molnar1df21052007-07-09 18:51:58 +0200402 * at least once to get things moving:
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200403 */
Ingo Molnar1df21052007-07-09 18:51:58 +0200404 init_idle_bootup_task(current);
Thomas Gleixnerbd2f5532011-03-21 12:33:18 +0100405 schedule_preempt_disabled();
Nick Piggin5bfb5d62005-11-08 21:39:01 -0800406 /* Call into cpu_idle with preempt disabled */
Thomas Gleixnera1a04ec2013-03-21 22:49:34 +0100407 cpu_startup_entry(CPUHP_ONLINE);
Ingo Molnar1df21052007-07-09 18:51:58 +0200408}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409
410/* Check for early params. */
Jim Cromie9fb48c72012-04-27 14:30:34 -0600411static int __init do_early_param(char *param, char *val, const char *unused)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412{
Rusty Russell914dcaa2010-08-11 23:04:18 -0600413 const struct obs_kernel_param *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414
415 for (p = __setup_start; p < __setup_end; p++) {
Michal Schmidtb1e4d202011-10-10 00:03:37 +0200416 if ((p->early && parameq(param, p->str)) ||
Yinghai Lu18a8bd92007-07-15 23:37:59 -0700417 (strcmp(param, "console") == 0 &&
418 strcmp(p->str, "earlycon") == 0)
419 ) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420 if (p->setup_func(val) != 0)
Andrew Mortonea676e82013-04-29 16:18:20 -0700421 pr_warn("Malformed early option '%s'\n", param);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422 }
423 }
424 /* We accept everything at this stage. */
425 return 0;
426}
427
Magnus Damm13977092009-03-30 14:37:25 -0700428void __init parse_early_options(char *cmdline)
429{
Pawel Moll026cee02012-03-26 12:50:51 +1030430 parse_args("early options", cmdline, NULL, 0, 0, 0, do_early_param);
Magnus Damm13977092009-03-30 14:37:25 -0700431}
432
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433/* Arch code calls this early on, or if not, just before other parsing. */
434void __init parse_early_param(void)
435{
Fabian Frederickdd4d9fe2014-08-08 14:23:44 -0700436 static int done __initdata;
437 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438
439 if (done)
440 return;
441
442 /* All fall through to do_early_param. */
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800443 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
Magnus Damm13977092009-03-30 14:37:25 -0700444 parse_early_options(tmp_cmdline);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445 done = 1;
446}
447
448/*
449 * Activate the first processor.
450 */
451
Stas Sergeev44fd2292006-03-23 02:59:44 -0800452static void __init boot_cpu_init(void)
453{
454 int cpu = smp_processor_id();
455 /* Mark the boot cpu "present", "online" etc for SMP and UP case */
Rusty Russell915441b2009-01-01 10:12:15 +1030456 set_cpu_online(cpu, true);
Peter Zijlstra933b0612009-12-16 18:04:31 +0100457 set_cpu_active(cpu, true);
Rusty Russell915441b2009-01-01 10:12:15 +1030458 set_cpu_present(cpu, true);
459 set_cpu_possible(cpu, true);
Stas Sergeev44fd2292006-03-23 02:59:44 -0800460}
461
Benjamin Herrenschmidt839ad622008-04-18 16:56:18 +1000462void __init __weak smp_setup_processor_id(void)
Andrew Morton033ab7f2006-06-30 01:55:50 -0700463{
464}
465
David Howellseded09c2012-11-02 13:20:42 +0000466# if THREAD_SIZE >= PAGE_SIZE
Benjamin Herrenschmidt8c9843e2008-04-18 16:56:15 +1000467void __init __weak thread_info_cache_init(void)
468{
469}
David Howellseded09c2012-11-02 13:20:42 +0000470#endif
Benjamin Herrenschmidt8c9843e2008-04-18 16:56:15 +1000471
Pekka Enberg444f4782009-06-11 18:29:06 +0300472/*
473 * Set up kernel memory allocators
474 */
475static void __init mm_init(void)
476{
Joonsoo Kimeefa864b2014-12-12 16:55:46 -0800477 /*
478 * page_ext requires contiguous pages,
479 * bigger than MAX_ORDER unless SPARSEMEM.
480 */
481 page_ext_init_flatmem();
Pekka Enberg444f4782009-06-11 18:29:06 +0300482 mem_init();
483 kmem_cache_init();
Tejun Heo099a19d2010-06-27 18:50:00 +0200484 percpu_init_late();
Kirill A. Shutemovb35f1812014-01-21 15:49:07 -0800485 pgtable_init();
Pekka Enberg444f4782009-06-11 18:29:06 +0300486 vmalloc_init();
487}
488
Andi Kleen722a9f92014-05-02 00:44:38 +0200489asmlinkage __visible void __init start_kernel(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490{
Fabian Frederickdd4d9fe2014-08-08 14:23:44 -0700491 char *command_line;
492 char *after_dashes;
Andrew Morton033ab7f2006-06-30 01:55:50 -0700493
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700494 /*
495 * Need to run as early as possible, to initialize the
496 * lockdep hash:
497 */
498 lockdep_init();
Aaron Tomlind4311ff2014-09-12 14:16:17 +0100499 set_task_stack_end_magic(&init_task);
Ming Lei73839c52011-11-17 13:34:31 +0800500 smp_setup_processor_id();
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700501 debug_objects_early_init();
Ingo Molnar42059422008-02-14 09:44:08 +0100502
503 /*
504 * Set up the the initial canary ASAP:
505 */
506 boot_init_stack_canary();
507
Paul Menageddbcc7e2007-10-18 23:39:30 -0700508 cgroup_init_early();
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700509
510 local_irq_disable();
Tejun Heo2ce802f2011-01-20 12:06:35 +0100511 early_boot_irqs_disabled = true;
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700512
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513/*
514 * Interrupts are still disabled. Do necessary setups, then
515 * enable them
516 */
Stas Sergeev44fd2292006-03-23 02:59:44 -0800517 boot_cpu_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518 page_address_init();
Andrew Mortonea676e82013-04-29 16:18:20 -0700519 pr_notice("%s", linux_banner);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 setup_arch(&command_line);
Linus Torvalds6345d242011-05-29 11:32:28 -0700521 mm_init_cpumask(&init_mm);
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800522 setup_command_line(command_line);
Mike Travise0982e92008-03-26 14:23:48 -0700523 setup_nr_cpu_ids();
Tejun Heod6647bd2009-07-21 17:11:50 +0900524 setup_per_cpu_areas();
Stas Sergeev44fd2292006-03-23 02:59:44 -0800525 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526
Jiang Liu9adb62a2012-07-31 16:43:28 -0700527 build_all_zonelists(NULL, NULL);
Pekka Enberg83b519e2009-06-10 19:40:04 +0300528 page_alloc_init();
529
Andrew Mortonea676e82013-04-29 16:18:20 -0700530 pr_notice("Kernel command line: %s\n", boot_command_line);
Pekka Enberg83b519e2009-06-10 19:40:04 +0300531 parse_early_param();
Rusty Russell51e158c2014-04-28 11:34:33 +0930532 after_dashes = parse_args("Booting kernel",
533 static_command_line, __start___param,
534 __stop___param - __start___param,
535 -1, -1, &unknown_bootoption);
Daniel Thompson3438cf52014-11-11 16:29:46 +1030536 if (!IS_ERR_OR_NULL(after_dashes))
Rusty Russell51e158c2014-04-28 11:34:33 +0930537 parse_args("Setting init args", after_dashes, NULL, 0, -1, -1,
538 set_init_arg);
Jeremy Fitzhardinge97ce2c82011-10-12 16:17:54 -0700539
540 jump_label_init();
541
Pekka Enberg83b519e2009-06-10 19:40:04 +0300542 /*
543 * These use large bootmem allocations and must precede
544 * kmem_cache_init()
545 */
Mike Travis162a7e72011-05-24 17:13:20 -0700546 setup_log_buf(0);
Pekka Enberg83b519e2009-06-10 19:40:04 +0300547 pidhash_init();
Pekka Enberg83b519e2009-06-10 19:40:04 +0300548 vfs_caches_init_early();
549 sort_main_extable();
550 trap_init();
Pekka Enberg444f4782009-06-11 18:29:06 +0300551 mm_init();
KOSAKI Motohirode03c722011-05-24 17:12:15 -0700552
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553 /*
554 * Set up the scheduler prior starting any interrupts (such as the
555 * timer interrupt). Full topology setup happens at smp_init()
556 * time - but meanwhile we still have a functioning scheduler.
557 */
558 sched_init();
559 /*
560 * Disable preemption - early bootup scheduling is extremely
561 * fragile until we cpu_idle() for the first time.
562 */
563 preempt_disable();
Fabian Frederickdd4d9fe2014-08-08 14:23:44 -0700564 if (WARN(!irqs_disabled(),
565 "Interrupts were enabled *very* early, fixing it\n"))
Ard van Breemenc4a68302007-01-05 16:36:19 -0800566 local_irq_disable();
Peter Zijlstra9f58a202010-11-17 23:17:35 +0100567 idr_init_cache();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568 rcu_init();
Steven Rostedt (Red Hat)5f893b22014-12-12 20:05:10 -0500569
570 /* trace_printk() and trace points may be used after this */
571 trace_init();
572
Frederic Weisbecker65f382f2013-07-11 19:12:32 +0200573 context_tracking_init();
Yinghai Lu773e3eb2010-02-10 01:20:33 -0800574 radix_tree_init();
Yinghai Lu0b8f1ef2008-12-05 18:58:31 -0800575 /* init some links before init_ISA_irqs() */
576 early_irq_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577 init_IRQ();
Thomas Gleixnerad2b1352013-03-05 15:14:05 +0100578 tick_init();
Linus Torvaldsd6dd50e2014-10-13 15:44:12 +0200579 rcu_init_nohz();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580 init_timers();
Thomas Gleixnerc0a31322006-01-09 20:52:32 -0800581 hrtimers_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700582 softirq_init();
john stultzad596172006-06-26 00:25:06 -0700583 timekeeping_init();
john stultz88fecaa2006-07-03 00:24:04 -0700584 time_init();
Stephen Boyd38ff87f2013-06-01 23:39:40 -0700585 sched_clock_postinit();
Stephane Eranian9e630202013-04-03 14:21:33 +0200586 perf_event_init();
Heiko Carstens93e02812006-07-03 00:24:24 -0700587 profile_init();
Takao Indohd8ad7d12011-03-29 12:35:04 -0400588 call_function_init();
Steven Rostedtf91eb622013-04-29 16:18:18 -0700589 WARN(!irqs_disabled(), "Interrupts were enabled early\n");
Tejun Heo2ce802f2011-01-20 12:06:35 +0100590 early_boot_irqs_disabled = false;
Heiko Carstens93e02812006-07-03 00:24:24 -0700591 local_irq_enable();
Benjamin Herrenschmidtdcce2842009-06-18 13:24:12 +1000592
Pekka Enberg7e85ee02009-06-12 14:03:06 +0300593 kmem_cache_init_late();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700594
595 /*
596 * HACK ALERT! This is early. We're enabling the console before
597 * we've done PCI setups etc, and console_init() must be aware of
598 * this. But we do want output early, in case something goes wrong.
599 */
600 console_init();
601 if (panic_later)
Tetsuo Handa499a4582014-01-23 15:54:56 -0800602 panic("Too many boot %s vars at `%s'", panic_later,
603 panic_param);
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700604
605 lockdep_info();
606
Ingo Molnar9a11b49a2006-07-03 00:24:33 -0700607 /*
608 * Need to run this when irqs are enabled, because it wants
609 * to self-test [hard/soft]-irqs on/off lock inversion bugs
610 * too:
611 */
612 locking_selftest();
613
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614#ifdef CONFIG_BLK_DEV_INITRD
615 if (initrd_start && !initrd_below_start_ok &&
Geert Uytterhoevenbd673c72008-07-29 22:33:36 -0700616 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
Andrew Mortonea676e82013-04-29 16:18:20 -0700617 pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n",
Geert Uytterhoevenbd673c72008-07-29 22:33:36 -0700618 page_to_pfn(virt_to_page((void *)initrd_start)),
619 min_low_pfn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700620 initrd_start = 0;
621 }
622#endif
Joonsoo Kimeefa864b2014-12-12 16:55:46 -0800623 page_ext_init();
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700624 debug_objects_mem_init();
Catalin Marinas9b090f22011-05-19 16:25:30 +0100625 kmemleak_init();
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700626 setup_per_cpu_pageset();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627 numa_policy_init();
628 if (late_time_init)
629 late_time_init();
Thomas Gleixnerfa84e9e2009-08-21 22:01:12 +0200630 sched_clock_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631 calibrate_delay();
632 pidmap_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633 anon_vma_init();
Rafael J. Wysockic4e1acb2014-03-13 00:22:58 +0100634 acpi_early_init();
Linus Torvalds11520e52012-12-15 15:15:24 -0800635#ifdef CONFIG_X86
Matt Fleming83e68182012-11-14 09:42:35 +0000636 if (efi_enabled(EFI_RUNTIME_SERVICES))
Linus Torvalds11520e52012-12-15 15:15:24 -0800637 efi_enter_virtual_mode();
638#endif
H. Peter Anvin197725d2014-05-04 10:00:49 -0700639#ifdef CONFIG_X86_ESPFIX64
H. Peter Anvin3891a042014-04-29 16:46:09 -0700640 /* Should be run before the first non-init thread is created */
641 init_espfix_bsp();
642#endif
Benjamin Herrenschmidt8c9843e2008-04-18 16:56:15 +1000643 thread_info_cache_init();
David Howellsd84f4f92008-11-14 10:39:23 +1100644 cred_init();
Jan Beulich44813742009-09-21 17:03:05 -0700645 fork_init(totalram_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646 proc_caches_init();
647 buffer_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700648 key_init();
649 security_init();
Jason Wessel0b4b3822010-05-20 21:04:29 -0500650 dbg_late_init();
Jan Beulich44813742009-09-21 17:03:05 -0700651 vfs_caches_init(totalram_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652 signals_init();
653 /* rootfs populating might need page-writeback */
654 page_writeback_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700655 proc_root_init();
Al Viroe149ed22014-11-01 10:57:28 -0400656 nsfs_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 cpuset_init();
Zefan Li695df212015-03-04 17:09:33 +0800658 cgroup_init();
Shailabh Nagarc7572492006-07-14 00:24:40 -0700659 taskstats_init_early();
Shailabh Nagarca74e922006-07-14 00:24:36 -0700660 delayacct_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661
662 check_bugs();
663
Feng Tang6ae69962009-08-14 15:13:46 -0400664 sfi_init_late();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665
Matt Fleming83e68182012-11-14 09:42:35 +0000666 if (efi_enabled(EFI_RUNTIME_SERVICES)) {
Josh Triplett2223af32012-09-28 17:57:05 -0700667 efi_late_init();
Josh Triplett78510792012-09-28 17:55:44 -0700668 efi_free_boot_services();
Josh Triplett2223af32012-09-28 17:57:05 -0700669 }
Josh Triplett78510792012-09-28 17:55:44 -0700670
Steven Rostedt68bf21a2008-08-14 15:45:08 -0400671 ftrace_init();
672
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673 /* Do the rest non-__init'ed, we're now alive */
674 rest_init();
675}
676
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -0700677/* Call all constructor functions linked into the kernel. */
678static void __init do_ctors(void)
679{
680#ifdef CONFIG_CONSTRUCTORS
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800681 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start;
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -0700682
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800683 for (; fn < (ctor_fn_t *) __ctors_end; fn++)
684 (*fn)();
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -0700685#endif
686}
687
Rusty Russell2329abf2012-01-13 09:32:18 +1030688bool initcall_debug;
Rusty Russelld0ea3d72008-10-22 10:00:23 -0500689core_param(initcall_debug, initcall_debug, bool, 0644);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690
Prarit Bhargava7b0b73d2014-06-04 16:12:17 -0700691#ifdef CONFIG_KALLSYMS
692struct blacklist_entry {
693 struct list_head next;
694 char *buf;
695};
696
697static __initdata_or_module LIST_HEAD(blacklisted_initcalls);
698
699static int __init initcall_blacklist(char *str)
700{
701 char *str_entry;
702 struct blacklist_entry *entry;
703
704 /* str argument is a comma-separated list of functions */
705 do {
706 str_entry = strsep(&str, ",");
707 if (str_entry) {
708 pr_debug("blacklisting initcall %s\n", str_entry);
709 entry = alloc_bootmem(sizeof(*entry));
710 entry->buf = alloc_bootmem(strlen(str_entry) + 1);
711 strcpy(entry->buf, str_entry);
712 list_add(&entry->next, &blacklisted_initcalls);
713 }
714 } while (str_entry);
715
716 return 0;
717}
718
719static bool __init_or_module initcall_blacklisted(initcall_t fn)
720{
721 struct list_head *tmp;
722 struct blacklist_entry *entry;
723 char *fn_name;
724
725 fn_name = kasprintf(GFP_KERNEL, "%pf", fn);
726 if (!fn_name)
727 return false;
728
729 list_for_each(tmp, &blacklisted_initcalls) {
730 entry = list_entry(tmp, struct blacklist_entry, next);
731 if (!strcmp(fn_name, entry->buf)) {
732 pr_debug("initcall %s blacklisted\n", fn_name);
733 kfree(fn_name);
734 return true;
735 }
736 }
737
738 kfree(fn_name);
739 return false;
740}
741#else
742static int __init initcall_blacklist(char *str)
743{
744 pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n");
745 return 0;
746}
747
748static bool __init_or_module initcall_blacklisted(initcall_t fn)
749{
750 return false;
751}
752#endif
753__setup("initcall_blacklist=", initcall_blacklist);
754
Kevin Winchestere4461272010-08-09 17:20:32 -0700755static int __init_or_module do_one_initcall_debug(initcall_t fn)
Linus Torvaldse0df1542008-05-15 18:14:01 -0700756{
Frederic Weisbecker74239072008-11-11 23:24:42 +0100757 ktime_t calltime, delta, rettime;
Américo Wang30dbb20e2010-05-26 18:57:53 +0800758 unsigned long long duration;
759 int ret;
Linus Torvaldse0df1542008-05-15 18:14:01 -0700760
Andrew Mortond62cf812014-06-04 16:12:16 -0700761 printk(KERN_DEBUG "calling %pF @ %i\n", fn, task_pid_nr(current));
Kevin Winchester22c5c032010-08-09 17:20:32 -0700762 calltime = ktime_get();
Américo Wang30dbb20e2010-05-26 18:57:53 +0800763 ret = fn();
Kevin Winchester22c5c032010-08-09 17:20:32 -0700764 rettime = ktime_get();
765 delta = ktime_sub(rettime, calltime);
766 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
Andrew Mortond62cf812014-06-04 16:12:16 -0700767 printk(KERN_DEBUG "initcall %pF returned %d after %lld usecs\n",
Andrew Mortonea676e82013-04-29 16:18:20 -0700768 fn, ret, duration);
Linus Torvaldse0df1542008-05-15 18:14:01 -0700769
Kevin Winchester22c5c032010-08-09 17:20:32 -0700770 return ret;
771}
772
Kevin Winchestere4461272010-08-09 17:20:32 -0700773int __init_or_module do_one_initcall(initcall_t fn)
Kevin Winchester22c5c032010-08-09 17:20:32 -0700774{
775 int count = preempt_count();
776 int ret;
Steven Rostedtff1c8fa2013-07-03 15:05:37 -0700777 char msgbuf[64];
Kevin Winchester22c5c032010-08-09 17:20:32 -0700778
Prarit Bhargava7b0b73d2014-06-04 16:12:17 -0700779 if (initcall_blacklisted(fn))
780 return -EPERM;
781
Kevin Winchester22c5c032010-08-09 17:20:32 -0700782 if (initcall_debug)
783 ret = do_one_initcall_debug(fn);
784 else
785 ret = fn();
Linus Torvaldse0df1542008-05-15 18:14:01 -0700786
787 msgbuf[0] = 0;
788
Linus Torvaldse0df1542008-05-15 18:14:01 -0700789 if (preempt_count() != count) {
Steven Rostedtbf5d7702013-05-01 13:35:51 -0400790 sprintf(msgbuf, "preemption imbalance ");
Peter Zijlstra4a2b4b22013-08-14 14:55:24 +0200791 preempt_count_set(count);
Linus Torvaldse0df1542008-05-15 18:14:01 -0700792 }
793 if (irqs_disabled()) {
Cyrill Gorcunova76bfd02008-05-15 13:52:41 -0700794 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf));
Linus Torvaldse0df1542008-05-15 18:14:01 -0700795 local_irq_enable();
796 }
Steven Rostedtf91eb622013-04-29 16:18:18 -0700797 WARN(msgbuf[0], "initcall %pF returned with %s\n", fn, msgbuf);
Arjan van de Ven59f94152008-07-30 12:49:02 -0700798
Américo Wang30dbb20e2010-05-26 18:57:53 +0800799 return ret;
Linus Torvaldse0df1542008-05-15 18:14:01 -0700800}
801
802
Pawel Moll026cee02012-03-26 12:50:51 +1030803extern initcall_t __initcall_start[];
804extern initcall_t __initcall0_start[];
805extern initcall_t __initcall1_start[];
806extern initcall_t __initcall2_start[];
807extern initcall_t __initcall3_start[];
808extern initcall_t __initcall4_start[];
809extern initcall_t __initcall5_start[];
810extern initcall_t __initcall6_start[];
811extern initcall_t __initcall7_start[];
812extern initcall_t __initcall_end[];
813
814static initcall_t *initcall_levels[] __initdata = {
815 __initcall0_start,
816 __initcall1_start,
817 __initcall2_start,
818 __initcall3_start,
819 __initcall4_start,
820 __initcall5_start,
821 __initcall6_start,
822 __initcall7_start,
823 __initcall_end,
824};
825
Jim Cromie96263d22012-06-14 16:00:59 -0600826/* Keep these in sync with initcalls in include/linux/init.h */
Pawel Moll026cee02012-03-26 12:50:51 +1030827static char *initcall_level_names[] __initdata = {
Jim Cromie9fb48c72012-04-27 14:30:34 -0600828 "early",
829 "core",
830 "postcore",
831 "arch",
832 "subsys",
833 "fs",
834 "device",
835 "late",
Pawel Moll026cee02012-03-26 12:50:51 +1030836};
837
Pawel Moll026cee02012-03-26 12:50:51 +1030838static void __init do_initcall_level(int level)
839{
Pawel Moll026cee02012-03-26 12:50:51 +1030840 initcall_t *fn;
841
Krzysztof Mazur08746a62013-10-31 13:45:39 +1030842 strcpy(initcall_command_line, saved_command_line);
Pawel Moll026cee02012-03-26 12:50:51 +1030843 parse_args(initcall_level_names[level],
Krzysztof Mazur08746a62013-10-31 13:45:39 +1030844 initcall_command_line, __start___param,
Pawel Moll026cee02012-03-26 12:50:51 +1030845 __stop___param - __start___param,
846 level, level,
Greg Kroah-Hartmaneb157422012-05-02 14:33:37 -0700847 &repair_env_string);
Pawel Moll026cee02012-03-26 12:50:51 +1030848
849 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++)
850 do_one_initcall(*fn);
851}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700852
853static void __init do_initcalls(void)
854{
Pawel Moll026cee02012-03-26 12:50:51 +1030855 int level;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856
Borislav Petkov19efb722012-06-01 18:56:00 +0200857 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++)
Pawel Moll026cee02012-03-26 12:50:51 +1030858 do_initcall_level(level);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859}
860
861/*
862 * Ok, the machine is now initialized. None of the devices
863 * have been touched yet, but the CPU subsystem is up and
864 * running, and memory and process management works.
865 *
866 * Now we can finally start doing some real work..
867 */
868static void __init do_basic_setup(void)
869{
Lai Jiangshan759ee092009-03-25 17:06:30 +0800870 cpuset_init_smp();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871 usermodehelper_init();
Hugh Dickins41ffe5d2011-08-03 16:21:21 -0700872 shmem_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700873 driver_init();
Eric W. Biedermanb04c3af2007-02-14 00:33:57 -0800874 init_irq_proc();
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -0700875 do_ctors();
Linus Torvaldsd5767c52011-09-28 10:23:44 -0700876 usermodehelper_enable();
wangyanqingb0f84372011-09-29 15:09:40 +0800877 do_initcalls();
Theodore Ts'o47d06e52013-09-10 10:52:35 -0400878 random_int_secret_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879}
880
Eduard - Gabriel Munteanu7babe8d2008-07-25 19:45:11 -0700881static void __init do_pre_smp_initcalls(void)
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700882{
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800883 initcall_t *fn;
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700884
Pawel Moll026cee02012-03-26 12:50:51 +1030885 for (fn = __initcall_start; fn < __initcall0_start; fn++)
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800886 do_one_initcall(*fn);
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700887}
888
Tejun Heobb813f42013-01-18 14:05:56 -0800889/*
890 * This function requests modules which should be loaded by default and is
891 * called twice right after initrd is mounted and right before init is
892 * exec'd. If such modules are on either initrd or rootfs, they will be
893 * loaded before control is passed to userland.
894 */
895void __init load_default_modules(void)
896{
897 load_default_elevator_module();
898}
899
Al Viroa74fb732012-10-10 21:28:25 -0400900static int run_init_process(const char *init_filename)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901{
902 argv_init[0] = init_filename;
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -0800903 return do_execve(getname_kernel(init_filename),
Al Viroae903ca2012-12-14 12:44:11 -0500904 (const char __user *const __user *)argv_init,
905 (const char __user *const __user *)envp_init);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906}
907
Michael Opdenackerba247622013-11-12 15:10:21 -0800908static int try_to_run_init_process(const char *init_filename)
909{
910 int ret;
911
912 ret = run_init_process(init_filename);
913
914 if (ret && ret != -ENOENT) {
915 pr_err("Starting init: %s exists but couldn't execute it (error %d)\n",
916 init_filename, ret);
917 }
918
919 return ret;
920}
921
Vineet Guptaf80b0c92012-12-21 12:25:44 +0530922static noinline void __init kernel_init_freeable(void);
Al Virod6b21232012-10-10 19:57:26 -0400923
924static int __ref kernel_init(void *unused)
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100925{
Michael Opdenackerba247622013-11-12 15:10:21 -0800926 int ret;
927
Al Virod6b21232012-10-10 19:57:26 -0400928 kernel_init_freeable();
Arjan van de Ven22a9d642009-01-07 08:45:46 -0800929 /* need to finish all async __init code before freeing the memory */
930 async_synchronize_full();
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100931 free_initmem();
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100932 mark_rodata_ro();
933 system_state = SYSTEM_RUNNING;
934 numa_default_policy();
935
Al Viro4a9d4b02012-06-24 09:56:45 +0400936 flush_delayed_fput();
Oleg Nesterovfae5fa42008-04-30 00:53:03 -0700937
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100938 if (ramdisk_execute_command) {
Michael Opdenackerba247622013-11-12 15:10:21 -0800939 ret = run_init_process(ramdisk_execute_command);
940 if (!ret)
Al Viroa74fb732012-10-10 21:28:25 -0400941 return 0;
Michael Opdenackerba247622013-11-12 15:10:21 -0800942 pr_err("Failed to execute %s (error %d)\n",
943 ramdisk_execute_command, ret);
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100944 }
945
946 /*
947 * We try each of these until one succeeds.
948 *
949 * The Bourne shell can be used instead of init if we are
950 * trying to recover a really broken machine.
951 */
952 if (execute_command) {
Michael Opdenackerba247622013-11-12 15:10:21 -0800953 ret = run_init_process(execute_command);
954 if (!ret)
Al Viroa74fb732012-10-10 21:28:25 -0400955 return 0;
Andy Lutomirski6ef45362014-12-10 15:52:19 -0800956 panic("Requested init %s failed (error %d).",
957 execute_command, ret);
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100958 }
Michael Opdenackerba247622013-11-12 15:10:21 -0800959 if (!try_to_run_init_process("/sbin/init") ||
960 !try_to_run_init_process("/etc/init") ||
961 !try_to_run_init_process("/bin/init") ||
962 !try_to_run_init_process("/bin/sh"))
Al Viroa74fb732012-10-10 21:28:25 -0400963 return 0;
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100964
Michael Opdenackerba247622013-11-12 15:10:21 -0800965 panic("No working init found. Try passing init= option to kernel. "
Andreas Mohr9a85b8d2010-03-05 13:42:39 -0800966 "See Linux Documentation/init.txt for guidance.");
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100967}
968
Vineet Guptaf80b0c92012-12-21 12:25:44 +0530969static noinline void __init kernel_init_freeable(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970{
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200971 /*
972 * Wait until kthreadd is all set-up.
973 */
974 wait_for_completion(&kthreadd_done);
Linus Torvalds31a67102012-05-21 12:52:42 -0700975
976 /* Now the scheduler is fully set up and can do blocking allocations */
977 gfp_allowed_mask = __GFP_BITS_MASK;
978
Miao Xie58568d22009-06-16 15:31:49 -0700979 /*
980 * init can allocate pages on any node
981 */
Lai Jiangshan3c466d42012-12-12 13:51:40 -0800982 set_mems_allowed(node_states[N_MEMORY]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700983 /*
984 * init can run on any cpu.
985 */
Rusty Russell1a2142a2009-03-30 22:05:10 -0600986 set_cpus_allowed_ptr(current, cpu_all_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700987
Cedric Le Goater9ec52092006-10-02 02:19:00 -0700988 cad_pid = task_pid(current);
989
Andi Kleenca74a6f2008-01-30 13:33:17 +0100990 smp_prepare_cpus(setup_max_cpus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700991
992 do_pre_smp_initcalls();
Peter Zijlstra004417a2010-11-25 18:38:29 +0100993 lockup_detector_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995 smp_init();
996 sched_init_smp();
997
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998 do_basic_setup();
999
Eric W. Biederman2bd3a9972010-03-02 23:53:19 -08001000 /* Open the /dev/console on the rootfs, this should never fail */
1001 if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
Andrew Mortonea676e82013-04-29 16:18:20 -07001002 pr_err("Warning: unable to open an initial console.\n");
Eric W. Biederman2bd3a9972010-03-02 23:53:19 -08001003
1004 (void) sys_dup(0);
1005 (void) sys_dup(0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006 /*
1007 * check if there is an early userspace init. If yes, let it do all
1008 * the work
1009 */
Olof Johanssonffdfc402005-09-06 15:17:19 -07001010
1011 if (!ramdisk_execute_command)
1012 ramdisk_execute_command = "/init";
1013
1014 if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
1015 ramdisk_execute_command = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016 prepare_namespace();
Olof Johanssonffdfc402005-09-06 15:17:19 -07001017 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001018
1019 /*
1020 * Ok, we have completed the initial bootup, and
1021 * we're essentially up and running. Get rid of the
1022 * initmem segments and start the user-mode stuff..
Dmitry Kasatkinc9cd2ce2014-11-05 17:01:15 +02001023 *
1024 * rootfs is available now, try loading the public keys
1025 * and default modules
Linus Torvalds1da177e2005-04-16 15:20:36 -07001026 */
Tejun Heobb813f42013-01-18 14:05:56 -08001027
Dmitry Kasatkinc9cd2ce2014-11-05 17:01:15 +02001028 integrity_load_keys();
Tejun Heobb813f42013-01-18 14:05:56 -08001029 load_default_modules();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001030}