blob: 61b993767db53e8401dc1223fa6e028f7edafd74 [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
Linus Torvalds1da177e2005-04-16 15:20:36 -070090#ifdef CONFIG_X86_LOCAL_APIC
91#include <asm/smp.h>
92#endif
93
Sam Ravnborgaae5f662007-02-26 16:45:41 +010094static int kernel_init(void *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070095
96extern void init_IRQ(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070097extern void fork_init(unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -070098extern void radix_tree_init(void);
Arjan van de Ven37b73c82006-01-06 00:12:01 -080099#ifndef CONFIG_DEBUG_RODATA
100static inline void mark_rodata_ro(void) { }
101#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102
Tejun Heo2ce802f2011-01-20 12:06:35 +0100103/*
104 * Debug helper: via this flag we know that we are in 'early bootup code'
105 * where only the boot processor is running with IRQ disabled. This means
106 * two things - IRQ must not be enabled before the flag is cleared and some
107 * operations which are not allowed with IRQ disabled are allowed while the
108 * flag is set.
109 */
110bool early_boot_irqs_disabled __read_mostly;
111
Paul E. McKenneya6826042009-02-25 18:03:42 -0800112enum system_states system_state __read_mostly;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113EXPORT_SYMBOL(system_state);
114
115/*
116 * Boot command-line arguments
117 */
118#define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
119#define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
120
121extern void time_init(void);
122/* Default late time init is NULL. archs can override this later. */
Jan Beulichd2e31922009-01-06 14:41:10 -0800123void (*__initdata late_time_init)(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800125/* Untouched command line saved by arch-specific code. */
126char __initdata boot_command_line[COMMAND_LINE_SIZE];
127/* Untouched saved command line (eg. for /proc) */
128char *saved_command_line;
129/* Command line for parameter parsing */
130static char *static_command_line;
Krzysztof Mazur08746a62013-10-31 13:45:39 +1030131/* Command line for per-initcall parameter parsing */
132static char *initcall_command_line;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133
134static char *execute_command;
Olof Johanssonffdfc402005-09-06 15:17:19 -0700135static char *ramdisk_execute_command;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136
Jan Beulich8b3b2952007-07-15 23:41:07 -0700137/*
Hannes Frederic Sowac4b2c0c2013-10-19 21:48:53 +0200138 * Used to generate warnings if static_key manipulation functions are used
139 * before jump_label_init is called.
140 */
Fabian Frederickdd4d9fe2014-08-08 14:23:44 -0700141bool static_key_initialized __read_mostly;
Hannes Frederic Sowac4b2c0c2013-10-19 21:48:53 +0200142EXPORT_SYMBOL_GPL(static_key_initialized);
143
144/*
Jan Beulich8b3b2952007-07-15 23:41:07 -0700145 * If set, this is an indication to the drivers that reset the underlying
146 * device before going ahead with the initialization otherwise driver might
147 * rely on the BIOS and skip the reset operation.
148 *
149 * This is useful if kernel is booting in an unreliable environment.
150 * For ex. kdump situaiton where previous kernel has crashed, BIOS has been
151 * skipped and devices will be in unknown state.
152 */
153unsigned int reset_devices;
154EXPORT_SYMBOL(reset_devices);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155
Vivek Goyal7e962872006-09-27 01:50:44 -0700156static int __init set_reset_devices(char *str)
157{
158 reset_devices = 1;
159 return 1;
160}
161
162__setup("reset_devices", set_reset_devices);
163
Fabian Frederickdd4d9fe2014-08-08 14:23:44 -0700164static const char *argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
165const char *envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166static const char *panic_later, *panic_param;
167
Rusty Russell914dcaa2010-08-11 23:04:18 -0600168extern const struct obs_kernel_param __setup_start[], __setup_end[];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169
170static int __init obsolete_checksetup(char *line)
171{
Rusty Russell914dcaa2010-08-11 23:04:18 -0600172 const struct obs_kernel_param *p;
Rusty Russell33df0d12006-09-26 10:52:32 +0200173 int had_early_param = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174
175 p = __setup_start;
176 do {
177 int n = strlen(p->str);
Michal Schmidtb1e4d202011-10-10 00:03:37 +0200178 if (parameqn(line, p->str, n)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 if (p->early) {
Rusty Russell33df0d12006-09-26 10:52:32 +0200180 /* Already done in parse_early_param?
181 * (Needs exact match on param part).
182 * Keep iterating, as we can have early
183 * params and __setups of same names 8( */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184 if (line[n] == '\0' || line[n] == '=')
Rusty Russell33df0d12006-09-26 10:52:32 +0200185 had_early_param = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 } else if (!p->setup_func) {
Andrew Mortonea676e82013-04-29 16:18:20 -0700187 pr_warn("Parameter %s is obsolete, ignored\n",
188 p->str);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189 return 1;
190 } else if (p->setup_func(line + n))
191 return 1;
192 }
193 p++;
194 } while (p < __setup_end);
Rusty Russell33df0d12006-09-26 10:52:32 +0200195
196 return had_early_param;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197}
198
199/*
200 * This should be approx 2 Bo*oMips to start (note initial shift), and will
201 * still work even if initially too large, it will just take slightly longer
202 */
203unsigned long loops_per_jiffy = (1<<12);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204EXPORT_SYMBOL(loops_per_jiffy);
205
206static int __init debug_kernel(char *str)
207{
Borislav Petkova8fe19e2014-06-04 16:11:46 -0700208 console_loglevel = CONSOLE_LOGLEVEL_DEBUG;
Yinghai Luf6f21c812008-02-08 04:21:58 -0800209 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210}
211
212static int __init quiet_kernel(char *str)
213{
Borislav Petkova8fe19e2014-06-04 16:11:46 -0700214 console_loglevel = CONSOLE_LOGLEVEL_QUIET;
Yinghai Luf6f21c812008-02-08 04:21:58 -0800215 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216}
217
Yinghai Luf6f21c812008-02-08 04:21:58 -0800218early_param("debug", debug_kernel);
219early_param("quiet", quiet_kernel);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220
221static int __init loglevel(char *str)
222{
Alexander Sverdlin808bf292011-09-21 09:51:40 +0200223 int newlevel;
224
225 /*
226 * Only update loglevel value when a correct setting was passed,
227 * to prevent blind crashes (when loglevel being set to 0) that
228 * are quite hard to debug
229 */
230 if (get_option(&str, &newlevel)) {
231 console_loglevel = newlevel;
232 return 0;
233 }
234
235 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236}
237
Yinghai Luf6f21c812008-02-08 04:21:58 -0800238early_param("loglevel", loglevel);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239
Chris Metcalfa99cd112012-04-06 12:53:50 -0400240/* Change NUL term back to "=", to make "param" the whole string. */
Greg Kroah-Hartmaneb157422012-05-02 14:33:37 -0700241static int __init repair_env_string(char *param, char *val, const char *unused)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 if (val) {
244 /* param=val or param="val"? */
245 if (val == param+strlen(param)+1)
246 val[-1] = '=';
247 else if (val == param+strlen(param)+2) {
248 val[-2] = '=';
249 memmove(val-1, val, strlen(val)+1);
250 val--;
251 } else
252 BUG();
253 }
Chris Metcalfa99cd112012-04-06 12:53:50 -0400254 return 0;
255}
256
Rusty Russell51e158c2014-04-28 11:34:33 +0930257/* Anything after -- gets handed straight to init. */
258static int __init set_init_arg(char *param, char *val, const char *unused)
259{
260 unsigned int i;
261
262 if (panic_later)
263 return 0;
264
265 repair_env_string(param, val, unused);
266
267 for (i = 0; argv_init[i]; i++) {
268 if (i == MAX_INIT_ARGS) {
269 panic_later = "init";
270 panic_param = param;
271 return 0;
272 }
273 }
274 argv_init[i] = param;
275 return 0;
276}
277
Chris Metcalfa99cd112012-04-06 12:53:50 -0400278/*
279 * Unknown boot options get handed to init, unless they look like
280 * unused parameters (modprobe will find them in /proc/cmdline).
281 */
Greg Kroah-Hartmaneb157422012-05-02 14:33:37 -0700282static int __init unknown_bootoption(char *param, char *val, const char *unused)
Chris Metcalfa99cd112012-04-06 12:53:50 -0400283{
Greg Kroah-Hartmaneb157422012-05-02 14:33:37 -0700284 repair_env_string(param, val, unused);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285
286 /* Handle obsolete-style parameters */
287 if (obsolete_checksetup(param))
288 return 0;
289
Rusty Russellf066a4f2009-12-01 14:56:44 +1030290 /* Unused module parameter. */
291 if (strchr(param, '.') && (!val || strchr(param, '.') < val))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293
294 if (panic_later)
295 return 0;
296
297 if (val) {
298 /* Environment option */
299 unsigned int i;
300 for (i = 0; envp_init[i]; i++) {
301 if (i == MAX_INIT_ENVS) {
Tetsuo Handa499a4582014-01-23 15:54:56 -0800302 panic_later = "env";
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 panic_param = param;
304 }
305 if (!strncmp(param, envp_init[i], val - param))
306 break;
307 }
308 envp_init[i] = param;
309 } else {
310 /* Command line option */
311 unsigned int i;
312 for (i = 0; argv_init[i]; i++) {
313 if (i == MAX_INIT_ARGS) {
Tetsuo Handa499a4582014-01-23 15:54:56 -0800314 panic_later = "init";
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315 panic_param = param;
316 }
317 }
318 argv_init[i] = param;
319 }
320 return 0;
321}
322
323static int __init init_setup(char *str)
324{
325 unsigned int i;
326
327 execute_command = str;
328 /*
329 * In case LILO is going to boot us with default command line,
330 * it prepends "auto" before the whole cmdline which makes
331 * the shell think it should execute a script with such name.
332 * So we ignore all arguments entered _before_ init=... [MJ]
333 */
334 for (i = 1; i < MAX_INIT_ARGS; i++)
335 argv_init[i] = NULL;
336 return 1;
337}
338__setup("init=", init_setup);
339
Olof Johanssonffdfc402005-09-06 15:17:19 -0700340static int __init rdinit_setup(char *str)
341{
342 unsigned int i;
343
344 ramdisk_execute_command = str;
345 /* See "auto" comment in init_setup */
346 for (i = 1; i < MAX_INIT_ARGS; i++)
347 argv_init[i] = NULL;
348 return 1;
349}
350__setup("rdinit=", rdinit_setup);
351
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352#ifndef CONFIG_SMP
Amerigo Wang34db18a02011-03-22 16:34:06 -0700353static const unsigned int setup_max_cpus = NR_CPUS;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354#ifdef CONFIG_X86_LOCAL_APIC
355static void __init smp_init(void)
356{
357 APIC_init_uniprocessor();
358}
359#else
360#define smp_init() do { } while (0)
361#endif
362
Mike Travise0982e92008-03-26 14:23:48 -0700363static inline void setup_nr_cpu_ids(void) { }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364static inline void smp_prepare_cpus(unsigned int maxcpus) { }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365#endif
366
367/*
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800368 * We need to store the untouched command line for future reference.
369 * We also need to store the touched command line since the parameter
370 * parsing is performed in place, and we should allow a component to
371 * store reference of name/value for future reference.
372 */
373static void __init setup_command_line(char *command_line)
374{
Santosh Shilimkar098b0812014-01-21 15:50:21 -0800375 saved_command_line =
376 memblock_virt_alloc(strlen(boot_command_line) + 1, 0);
377 initcall_command_line =
378 memblock_virt_alloc(strlen(boot_command_line) + 1, 0);
379 static_command_line = memblock_virt_alloc(strlen(command_line) + 1, 0);
Fabian Frederickdd4d9fe2014-08-08 14:23:44 -0700380 strcpy(saved_command_line, boot_command_line);
381 strcpy(static_command_line, command_line);
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800382}
383
384/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385 * We need to finalize in a non-__init function or else race conditions
386 * between the root thread and the init thread may cause start_kernel to
387 * be reaped by free_initmem before the root thread has proceeded to
388 * cpu_idle.
389 *
390 * gcc-3.4 accidentally inlines this function, so use noinline.
391 */
392
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200393static __initdata DECLARE_COMPLETION(kthreadd_done);
394
Rakib Mullickf99ebf02009-01-06 14:40:38 -0800395static noinline void __init_refok rest_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396{
Eric W. Biederman73c27992007-05-09 02:34:32 -0700397 int pid;
398
Paul E. McKenney7db905e2009-09-02 14:01:24 -0700399 rcu_scheduler_starting();
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200400 /*
Peter Zijlstra97158562010-06-30 10:37:11 +0200401 * We need to spawn init first so that it obtains pid 1, however
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200402 * the init task will end up wanting to create kthreads, which, if
403 * we schedule it before we create kthreadd, will OOPS.
404 */
Oleg Nesterov34a1b722014-06-04 16:12:19 -0700405 kernel_thread(kernel_init, NULL, CLONE_FS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406 numa_default_policy();
Eric W. Biederman73c27992007-05-09 02:34:32 -0700407 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
Paul E. McKenneyd11c5632010-02-22 17:04:50 -0800408 rcu_read_lock();
Pavel Emelyanov5cd20452008-04-30 00:54:24 -0700409 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
Paul E. McKenneyd11c5632010-02-22 17:04:50 -0800410 rcu_read_unlock();
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200411 complete(&kthreadd_done);
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200412
413 /*
414 * The boot idle thread must execute schedule()
Ingo Molnar1df21052007-07-09 18:51:58 +0200415 * at least once to get things moving:
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200416 */
Ingo Molnar1df21052007-07-09 18:51:58 +0200417 init_idle_bootup_task(current);
Thomas Gleixnerbd2f5532011-03-21 12:33:18 +0100418 schedule_preempt_disabled();
Nick Piggin5bfb5d62005-11-08 21:39:01 -0800419 /* Call into cpu_idle with preempt disabled */
Thomas Gleixnera1a04ec2013-03-21 22:49:34 +0100420 cpu_startup_entry(CPUHP_ONLINE);
Ingo Molnar1df21052007-07-09 18:51:58 +0200421}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422
423/* Check for early params. */
Jim Cromie9fb48c72012-04-27 14:30:34 -0600424static int __init do_early_param(char *param, char *val, const char *unused)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425{
Rusty Russell914dcaa2010-08-11 23:04:18 -0600426 const struct obs_kernel_param *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427
428 for (p = __setup_start; p < __setup_end; p++) {
Michal Schmidtb1e4d202011-10-10 00:03:37 +0200429 if ((p->early && parameq(param, p->str)) ||
Yinghai Lu18a8bd92007-07-15 23:37:59 -0700430 (strcmp(param, "console") == 0 &&
431 strcmp(p->str, "earlycon") == 0)
432 ) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 if (p->setup_func(val) != 0)
Andrew Mortonea676e82013-04-29 16:18:20 -0700434 pr_warn("Malformed early option '%s'\n", param);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435 }
436 }
437 /* We accept everything at this stage. */
438 return 0;
439}
440
Magnus Damm13977092009-03-30 14:37:25 -0700441void __init parse_early_options(char *cmdline)
442{
Pawel Moll026cee02012-03-26 12:50:51 +1030443 parse_args("early options", cmdline, NULL, 0, 0, 0, do_early_param);
Magnus Damm13977092009-03-30 14:37:25 -0700444}
445
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446/* Arch code calls this early on, or if not, just before other parsing. */
447void __init parse_early_param(void)
448{
Fabian Frederickdd4d9fe2014-08-08 14:23:44 -0700449 static int done __initdata;
450 static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451
452 if (done)
453 return;
454
455 /* All fall through to do_early_param. */
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800456 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
Magnus Damm13977092009-03-30 14:37:25 -0700457 parse_early_options(tmp_cmdline);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 done = 1;
459}
460
461/*
462 * Activate the first processor.
463 */
464
Stas Sergeev44fd2292006-03-23 02:59:44 -0800465static void __init boot_cpu_init(void)
466{
467 int cpu = smp_processor_id();
468 /* Mark the boot cpu "present", "online" etc for SMP and UP case */
Rusty Russell915441b2009-01-01 10:12:15 +1030469 set_cpu_online(cpu, true);
Peter Zijlstra933b0612009-12-16 18:04:31 +0100470 set_cpu_active(cpu, true);
Rusty Russell915441b2009-01-01 10:12:15 +1030471 set_cpu_present(cpu, true);
472 set_cpu_possible(cpu, true);
Stas Sergeev44fd2292006-03-23 02:59:44 -0800473}
474
Benjamin Herrenschmidt839ad622008-04-18 16:56:18 +1000475void __init __weak smp_setup_processor_id(void)
Andrew Morton033ab7f2006-06-30 01:55:50 -0700476{
477}
478
David Howellseded09c2012-11-02 13:20:42 +0000479# if THREAD_SIZE >= PAGE_SIZE
Benjamin Herrenschmidt8c9843e2008-04-18 16:56:15 +1000480void __init __weak thread_info_cache_init(void)
481{
482}
David Howellseded09c2012-11-02 13:20:42 +0000483#endif
Benjamin Herrenschmidt8c9843e2008-04-18 16:56:15 +1000484
Pekka Enberg444f4782009-06-11 18:29:06 +0300485/*
486 * Set up kernel memory allocators
487 */
488static void __init mm_init(void)
489{
Joonsoo Kimeefa864b2014-12-12 16:55:46 -0800490 /*
491 * page_ext requires contiguous pages,
492 * bigger than MAX_ORDER unless SPARSEMEM.
493 */
494 page_ext_init_flatmem();
Pekka Enberg444f4782009-06-11 18:29:06 +0300495 mem_init();
496 kmem_cache_init();
Tejun Heo099a19d2010-06-27 18:50:00 +0200497 percpu_init_late();
Kirill A. Shutemovb35f1812014-01-21 15:49:07 -0800498 pgtable_init();
Pekka Enberg444f4782009-06-11 18:29:06 +0300499 vmalloc_init();
500}
501
Andi Kleen722a9f92014-05-02 00:44:38 +0200502asmlinkage __visible void __init start_kernel(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503{
Fabian Frederickdd4d9fe2014-08-08 14:23:44 -0700504 char *command_line;
505 char *after_dashes;
Andrew Morton033ab7f2006-06-30 01:55:50 -0700506
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700507 /*
508 * Need to run as early as possible, to initialize the
509 * lockdep hash:
510 */
511 lockdep_init();
Aaron Tomlind4311ff2014-09-12 14:16:17 +0100512 set_task_stack_end_magic(&init_task);
Ming Lei73839c52011-11-17 13:34:31 +0800513 smp_setup_processor_id();
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700514 debug_objects_early_init();
Ingo Molnar42059422008-02-14 09:44:08 +0100515
516 /*
517 * Set up the the initial canary ASAP:
518 */
519 boot_init_stack_canary();
520
Paul Menageddbcc7e2007-10-18 23:39:30 -0700521 cgroup_init_early();
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700522
523 local_irq_disable();
Tejun Heo2ce802f2011-01-20 12:06:35 +0100524 early_boot_irqs_disabled = true;
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700525
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526/*
527 * Interrupts are still disabled. Do necessary setups, then
528 * enable them
529 */
Stas Sergeev44fd2292006-03-23 02:59:44 -0800530 boot_cpu_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 page_address_init();
Andrew Mortonea676e82013-04-29 16:18:20 -0700532 pr_notice("%s", linux_banner);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533 setup_arch(&command_line);
Linus Torvalds6345d242011-05-29 11:32:28 -0700534 mm_init_cpumask(&init_mm);
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800535 setup_command_line(command_line);
Mike Travise0982e92008-03-26 14:23:48 -0700536 setup_nr_cpu_ids();
Tejun Heod6647bd2009-07-21 17:11:50 +0900537 setup_per_cpu_areas();
Stas Sergeev44fd2292006-03-23 02:59:44 -0800538 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539
Jiang Liu9adb62a2012-07-31 16:43:28 -0700540 build_all_zonelists(NULL, NULL);
Pekka Enberg83b519e2009-06-10 19:40:04 +0300541 page_alloc_init();
542
Andrew Mortonea676e82013-04-29 16:18:20 -0700543 pr_notice("Kernel command line: %s\n", boot_command_line);
Pekka Enberg83b519e2009-06-10 19:40:04 +0300544 parse_early_param();
Rusty Russell51e158c2014-04-28 11:34:33 +0930545 after_dashes = parse_args("Booting kernel",
546 static_command_line, __start___param,
547 __stop___param - __start___param,
548 -1, -1, &unknown_bootoption);
Daniel Thompson3438cf52014-11-11 16:29:46 +1030549 if (!IS_ERR_OR_NULL(after_dashes))
Rusty Russell51e158c2014-04-28 11:34:33 +0930550 parse_args("Setting init args", after_dashes, NULL, 0, -1, -1,
551 set_init_arg);
Jeremy Fitzhardinge97ce2c82011-10-12 16:17:54 -0700552
553 jump_label_init();
554
Pekka Enberg83b519e2009-06-10 19:40:04 +0300555 /*
556 * These use large bootmem allocations and must precede
557 * kmem_cache_init()
558 */
Mike Travis162a7e72011-05-24 17:13:20 -0700559 setup_log_buf(0);
Pekka Enberg83b519e2009-06-10 19:40:04 +0300560 pidhash_init();
Pekka Enberg83b519e2009-06-10 19:40:04 +0300561 vfs_caches_init_early();
562 sort_main_extable();
563 trap_init();
Pekka Enberg444f4782009-06-11 18:29:06 +0300564 mm_init();
KOSAKI Motohirode03c722011-05-24 17:12:15 -0700565
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566 /*
567 * Set up the scheduler prior starting any interrupts (such as the
568 * timer interrupt). Full topology setup happens at smp_init()
569 * time - but meanwhile we still have a functioning scheduler.
570 */
571 sched_init();
572 /*
573 * Disable preemption - early bootup scheduling is extremely
574 * fragile until we cpu_idle() for the first time.
575 */
576 preempt_disable();
Fabian Frederickdd4d9fe2014-08-08 14:23:44 -0700577 if (WARN(!irqs_disabled(),
578 "Interrupts were enabled *very* early, fixing it\n"))
Ard van Breemenc4a68302007-01-05 16:36:19 -0800579 local_irq_disable();
Peter Zijlstra9f58a202010-11-17 23:17:35 +0100580 idr_init_cache();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 rcu_init();
Steven Rostedt (Red Hat)5f893b22014-12-12 20:05:10 -0500582
583 /* trace_printk() and trace points may be used after this */
584 trace_init();
585
Frederic Weisbecker65f382f2013-07-11 19:12:32 +0200586 context_tracking_init();
Yinghai Lu773e3eb2010-02-10 01:20:33 -0800587 radix_tree_init();
Yinghai Lu0b8f1ef2008-12-05 18:58:31 -0800588 /* init some links before init_ISA_irqs() */
589 early_irq_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 init_IRQ();
Thomas Gleixnerad2b1352013-03-05 15:14:05 +0100591 tick_init();
Linus Torvaldsd6dd50e2014-10-13 15:44:12 +0200592 rcu_init_nohz();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 init_timers();
Thomas Gleixnerc0a31322006-01-09 20:52:32 -0800594 hrtimers_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700595 softirq_init();
john stultzad596172006-06-26 00:25:06 -0700596 timekeeping_init();
john stultz88fecaa2006-07-03 00:24:04 -0700597 time_init();
Stephen Boyd38ff87f2013-06-01 23:39:40 -0700598 sched_clock_postinit();
Stephane Eranian9e630202013-04-03 14:21:33 +0200599 perf_event_init();
Heiko Carstens93e02812006-07-03 00:24:24 -0700600 profile_init();
Takao Indohd8ad7d12011-03-29 12:35:04 -0400601 call_function_init();
Steven Rostedtf91eb622013-04-29 16:18:18 -0700602 WARN(!irqs_disabled(), "Interrupts were enabled early\n");
Tejun Heo2ce802f2011-01-20 12:06:35 +0100603 early_boot_irqs_disabled = false;
Heiko Carstens93e02812006-07-03 00:24:24 -0700604 local_irq_enable();
Benjamin Herrenschmidtdcce2842009-06-18 13:24:12 +1000605
Pekka Enberg7e85ee02009-06-12 14:03:06 +0300606 kmem_cache_init_late();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607
608 /*
609 * HACK ALERT! This is early. We're enabling the console before
610 * we've done PCI setups etc, and console_init() must be aware of
611 * this. But we do want output early, in case something goes wrong.
612 */
613 console_init();
614 if (panic_later)
Tetsuo Handa499a4582014-01-23 15:54:56 -0800615 panic("Too many boot %s vars at `%s'", panic_later,
616 panic_param);
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700617
618 lockdep_info();
619
Ingo Molnar9a11b49a2006-07-03 00:24:33 -0700620 /*
621 * Need to run this when irqs are enabled, because it wants
622 * to self-test [hard/soft]-irqs on/off lock inversion bugs
623 * too:
624 */
625 locking_selftest();
626
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627#ifdef CONFIG_BLK_DEV_INITRD
628 if (initrd_start && !initrd_below_start_ok &&
Geert Uytterhoevenbd673c72008-07-29 22:33:36 -0700629 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
Andrew Mortonea676e82013-04-29 16:18:20 -0700630 pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n",
Geert Uytterhoevenbd673c72008-07-29 22:33:36 -0700631 page_to_pfn(virt_to_page((void *)initrd_start)),
632 min_low_pfn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633 initrd_start = 0;
634 }
635#endif
Joonsoo Kimeefa864b2014-12-12 16:55:46 -0800636 page_ext_init();
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700637 debug_objects_mem_init();
Catalin Marinas9b090f22011-05-19 16:25:30 +0100638 kmemleak_init();
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700639 setup_per_cpu_pageset();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640 numa_policy_init();
641 if (late_time_init)
642 late_time_init();
Thomas Gleixnerfa84e9e2009-08-21 22:01:12 +0200643 sched_clock_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644 calibrate_delay();
645 pidmap_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646 anon_vma_init();
Rafael J. Wysockic4e1acb2014-03-13 00:22:58 +0100647 acpi_early_init();
Linus Torvalds11520e52012-12-15 15:15:24 -0800648#ifdef CONFIG_X86
Matt Fleming83e68182012-11-14 09:42:35 +0000649 if (efi_enabled(EFI_RUNTIME_SERVICES))
Linus Torvalds11520e52012-12-15 15:15:24 -0800650 efi_enter_virtual_mode();
651#endif
H. Peter Anvin197725d2014-05-04 10:00:49 -0700652#ifdef CONFIG_X86_ESPFIX64
H. Peter Anvin3891a042014-04-29 16:46:09 -0700653 /* Should be run before the first non-init thread is created */
654 init_espfix_bsp();
655#endif
Benjamin Herrenschmidt8c9843e2008-04-18 16:56:15 +1000656 thread_info_cache_init();
David Howellsd84f4f92008-11-14 10:39:23 +1100657 cred_init();
Jan Beulich44813742009-09-21 17:03:05 -0700658 fork_init(totalram_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659 proc_caches_init();
660 buffer_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661 key_init();
662 security_init();
Jason Wessel0b4b3822010-05-20 21:04:29 -0500663 dbg_late_init();
Jan Beulich44813742009-09-21 17:03:05 -0700664 vfs_caches_init(totalram_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665 signals_init();
666 /* rootfs populating might need page-writeback */
667 page_writeback_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668 proc_root_init();
Al Viroe149ed22014-11-01 10:57:28 -0400669 nsfs_init();
Paul Menageddbcc7e2007-10-18 23:39:30 -0700670 cgroup_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671 cpuset_init();
Shailabh Nagarc7572492006-07-14 00:24:40 -0700672 taskstats_init_early();
Shailabh Nagarca74e922006-07-14 00:24:36 -0700673 delayacct_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674
675 check_bugs();
676
Feng Tang6ae69962009-08-14 15:13:46 -0400677 sfi_init_late();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700678
Matt Fleming83e68182012-11-14 09:42:35 +0000679 if (efi_enabled(EFI_RUNTIME_SERVICES)) {
Josh Triplett2223af32012-09-28 17:57:05 -0700680 efi_late_init();
Josh Triplett78510792012-09-28 17:55:44 -0700681 efi_free_boot_services();
Josh Triplett2223af32012-09-28 17:57:05 -0700682 }
Josh Triplett78510792012-09-28 17:55:44 -0700683
Steven Rostedt68bf21a2008-08-14 15:45:08 -0400684 ftrace_init();
685
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 /* Do the rest non-__init'ed, we're now alive */
687 rest_init();
688}
689
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -0700690/* Call all constructor functions linked into the kernel. */
691static void __init do_ctors(void)
692{
693#ifdef CONFIG_CONSTRUCTORS
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800694 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start;
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -0700695
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800696 for (; fn < (ctor_fn_t *) __ctors_end; fn++)
697 (*fn)();
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -0700698#endif
699}
700
Rusty Russell2329abf2012-01-13 09:32:18 +1030701bool initcall_debug;
Rusty Russelld0ea3d72008-10-22 10:00:23 -0500702core_param(initcall_debug, initcall_debug, bool, 0644);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703
Prarit Bhargava7b0b73d2014-06-04 16:12:17 -0700704#ifdef CONFIG_KALLSYMS
705struct blacklist_entry {
706 struct list_head next;
707 char *buf;
708};
709
710static __initdata_or_module LIST_HEAD(blacklisted_initcalls);
711
712static int __init initcall_blacklist(char *str)
713{
714 char *str_entry;
715 struct blacklist_entry *entry;
716
717 /* str argument is a comma-separated list of functions */
718 do {
719 str_entry = strsep(&str, ",");
720 if (str_entry) {
721 pr_debug("blacklisting initcall %s\n", str_entry);
722 entry = alloc_bootmem(sizeof(*entry));
723 entry->buf = alloc_bootmem(strlen(str_entry) + 1);
724 strcpy(entry->buf, str_entry);
725 list_add(&entry->next, &blacklisted_initcalls);
726 }
727 } while (str_entry);
728
729 return 0;
730}
731
732static bool __init_or_module initcall_blacklisted(initcall_t fn)
733{
734 struct list_head *tmp;
735 struct blacklist_entry *entry;
736 char *fn_name;
737
738 fn_name = kasprintf(GFP_KERNEL, "%pf", fn);
739 if (!fn_name)
740 return false;
741
742 list_for_each(tmp, &blacklisted_initcalls) {
743 entry = list_entry(tmp, struct blacklist_entry, next);
744 if (!strcmp(fn_name, entry->buf)) {
745 pr_debug("initcall %s blacklisted\n", fn_name);
746 kfree(fn_name);
747 return true;
748 }
749 }
750
751 kfree(fn_name);
752 return false;
753}
754#else
755static int __init initcall_blacklist(char *str)
756{
757 pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n");
758 return 0;
759}
760
761static bool __init_or_module initcall_blacklisted(initcall_t fn)
762{
763 return false;
764}
765#endif
766__setup("initcall_blacklist=", initcall_blacklist);
767
Kevin Winchestere4461272010-08-09 17:20:32 -0700768static int __init_or_module do_one_initcall_debug(initcall_t fn)
Linus Torvaldse0df1542008-05-15 18:14:01 -0700769{
Frederic Weisbecker74239072008-11-11 23:24:42 +0100770 ktime_t calltime, delta, rettime;
Américo Wang30dbb20e2010-05-26 18:57:53 +0800771 unsigned long long duration;
772 int ret;
Linus Torvaldse0df1542008-05-15 18:14:01 -0700773
Andrew Mortond62cf812014-06-04 16:12:16 -0700774 printk(KERN_DEBUG "calling %pF @ %i\n", fn, task_pid_nr(current));
Kevin Winchester22c5c032010-08-09 17:20:32 -0700775 calltime = ktime_get();
Américo Wang30dbb20e2010-05-26 18:57:53 +0800776 ret = fn();
Kevin Winchester22c5c032010-08-09 17:20:32 -0700777 rettime = ktime_get();
778 delta = ktime_sub(rettime, calltime);
779 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
Andrew Mortond62cf812014-06-04 16:12:16 -0700780 printk(KERN_DEBUG "initcall %pF returned %d after %lld usecs\n",
Andrew Mortonea676e82013-04-29 16:18:20 -0700781 fn, ret, duration);
Linus Torvaldse0df1542008-05-15 18:14:01 -0700782
Kevin Winchester22c5c032010-08-09 17:20:32 -0700783 return ret;
784}
785
Kevin Winchestere4461272010-08-09 17:20:32 -0700786int __init_or_module do_one_initcall(initcall_t fn)
Kevin Winchester22c5c032010-08-09 17:20:32 -0700787{
788 int count = preempt_count();
789 int ret;
Steven Rostedtff1c8fa2013-07-03 15:05:37 -0700790 char msgbuf[64];
Kevin Winchester22c5c032010-08-09 17:20:32 -0700791
Prarit Bhargava7b0b73d2014-06-04 16:12:17 -0700792 if (initcall_blacklisted(fn))
793 return -EPERM;
794
Kevin Winchester22c5c032010-08-09 17:20:32 -0700795 if (initcall_debug)
796 ret = do_one_initcall_debug(fn);
797 else
798 ret = fn();
Linus Torvaldse0df1542008-05-15 18:14:01 -0700799
800 msgbuf[0] = 0;
801
Linus Torvaldse0df1542008-05-15 18:14:01 -0700802 if (preempt_count() != count) {
Steven Rostedtbf5d7702013-05-01 13:35:51 -0400803 sprintf(msgbuf, "preemption imbalance ");
Peter Zijlstra4a2b4b22013-08-14 14:55:24 +0200804 preempt_count_set(count);
Linus Torvaldse0df1542008-05-15 18:14:01 -0700805 }
806 if (irqs_disabled()) {
Cyrill Gorcunova76bfd02008-05-15 13:52:41 -0700807 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf));
Linus Torvaldse0df1542008-05-15 18:14:01 -0700808 local_irq_enable();
809 }
Steven Rostedtf91eb622013-04-29 16:18:18 -0700810 WARN(msgbuf[0], "initcall %pF returned with %s\n", fn, msgbuf);
Arjan van de Ven59f94152008-07-30 12:49:02 -0700811
Américo Wang30dbb20e2010-05-26 18:57:53 +0800812 return ret;
Linus Torvaldse0df1542008-05-15 18:14:01 -0700813}
814
815
Pawel Moll026cee02012-03-26 12:50:51 +1030816extern initcall_t __initcall_start[];
817extern initcall_t __initcall0_start[];
818extern initcall_t __initcall1_start[];
819extern initcall_t __initcall2_start[];
820extern initcall_t __initcall3_start[];
821extern initcall_t __initcall4_start[];
822extern initcall_t __initcall5_start[];
823extern initcall_t __initcall6_start[];
824extern initcall_t __initcall7_start[];
825extern initcall_t __initcall_end[];
826
827static initcall_t *initcall_levels[] __initdata = {
828 __initcall0_start,
829 __initcall1_start,
830 __initcall2_start,
831 __initcall3_start,
832 __initcall4_start,
833 __initcall5_start,
834 __initcall6_start,
835 __initcall7_start,
836 __initcall_end,
837};
838
Jim Cromie96263d22012-06-14 16:00:59 -0600839/* Keep these in sync with initcalls in include/linux/init.h */
Pawel Moll026cee02012-03-26 12:50:51 +1030840static char *initcall_level_names[] __initdata = {
Jim Cromie9fb48c72012-04-27 14:30:34 -0600841 "early",
842 "core",
843 "postcore",
844 "arch",
845 "subsys",
846 "fs",
847 "device",
848 "late",
Pawel Moll026cee02012-03-26 12:50:51 +1030849};
850
Pawel Moll026cee02012-03-26 12:50:51 +1030851static void __init do_initcall_level(int level)
852{
Pawel Moll026cee02012-03-26 12:50:51 +1030853 initcall_t *fn;
854
Krzysztof Mazur08746a62013-10-31 13:45:39 +1030855 strcpy(initcall_command_line, saved_command_line);
Pawel Moll026cee02012-03-26 12:50:51 +1030856 parse_args(initcall_level_names[level],
Krzysztof Mazur08746a62013-10-31 13:45:39 +1030857 initcall_command_line, __start___param,
Pawel Moll026cee02012-03-26 12:50:51 +1030858 __stop___param - __start___param,
859 level, level,
Greg Kroah-Hartmaneb157422012-05-02 14:33:37 -0700860 &repair_env_string);
Pawel Moll026cee02012-03-26 12:50:51 +1030861
862 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++)
863 do_one_initcall(*fn);
864}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700865
866static void __init do_initcalls(void)
867{
Pawel Moll026cee02012-03-26 12:50:51 +1030868 int level;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700869
Borislav Petkov19efb722012-06-01 18:56:00 +0200870 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++)
Pawel Moll026cee02012-03-26 12:50:51 +1030871 do_initcall_level(level);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872}
873
874/*
875 * Ok, the machine is now initialized. None of the devices
876 * have been touched yet, but the CPU subsystem is up and
877 * running, and memory and process management works.
878 *
879 * Now we can finally start doing some real work..
880 */
881static void __init do_basic_setup(void)
882{
Lai Jiangshan759ee092009-03-25 17:06:30 +0800883 cpuset_init_smp();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884 usermodehelper_init();
Hugh Dickins41ffe5d2011-08-03 16:21:21 -0700885 shmem_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700886 driver_init();
Eric W. Biedermanb04c3af2007-02-14 00:33:57 -0800887 init_irq_proc();
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -0700888 do_ctors();
Linus Torvaldsd5767c52011-09-28 10:23:44 -0700889 usermodehelper_enable();
wangyanqingb0f84372011-09-29 15:09:40 +0800890 do_initcalls();
Theodore Ts'o47d06e52013-09-10 10:52:35 -0400891 random_int_secret_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700892}
893
Eduard - Gabriel Munteanu7babe8d2008-07-25 19:45:11 -0700894static void __init do_pre_smp_initcalls(void)
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700895{
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800896 initcall_t *fn;
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700897
Pawel Moll026cee02012-03-26 12:50:51 +1030898 for (fn = __initcall_start; fn < __initcall0_start; fn++)
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800899 do_one_initcall(*fn);
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700900}
901
Tejun Heobb813f42013-01-18 14:05:56 -0800902/*
903 * This function requests modules which should be loaded by default and is
904 * called twice right after initrd is mounted and right before init is
905 * exec'd. If such modules are on either initrd or rootfs, they will be
906 * loaded before control is passed to userland.
907 */
908void __init load_default_modules(void)
909{
910 load_default_elevator_module();
911}
912
Al Viroa74fb732012-10-10 21:28:25 -0400913static int run_init_process(const char *init_filename)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700914{
915 argv_init[0] = init_filename;
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -0800916 return do_execve(getname_kernel(init_filename),
Al Viroae903ca2012-12-14 12:44:11 -0500917 (const char __user *const __user *)argv_init,
918 (const char __user *const __user *)envp_init);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700919}
920
Michael Opdenackerba247622013-11-12 15:10:21 -0800921static int try_to_run_init_process(const char *init_filename)
922{
923 int ret;
924
925 ret = run_init_process(init_filename);
926
927 if (ret && ret != -ENOENT) {
928 pr_err("Starting init: %s exists but couldn't execute it (error %d)\n",
929 init_filename, ret);
930 }
931
932 return ret;
933}
934
Vineet Guptaf80b0c92012-12-21 12:25:44 +0530935static noinline void __init kernel_init_freeable(void);
Al Virod6b21232012-10-10 19:57:26 -0400936
937static int __ref kernel_init(void *unused)
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100938{
Michael Opdenackerba247622013-11-12 15:10:21 -0800939 int ret;
940
Al Virod6b21232012-10-10 19:57:26 -0400941 kernel_init_freeable();
Arjan van de Ven22a9d642009-01-07 08:45:46 -0800942 /* need to finish all async __init code before freeing the memory */
943 async_synchronize_full();
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100944 free_initmem();
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100945 mark_rodata_ro();
946 system_state = SYSTEM_RUNNING;
947 numa_default_policy();
948
Al Viro4a9d4b02012-06-24 09:56:45 +0400949 flush_delayed_fput();
Oleg Nesterovfae5fa42008-04-30 00:53:03 -0700950
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100951 if (ramdisk_execute_command) {
Michael Opdenackerba247622013-11-12 15:10:21 -0800952 ret = run_init_process(ramdisk_execute_command);
953 if (!ret)
Al Viroa74fb732012-10-10 21:28:25 -0400954 return 0;
Michael Opdenackerba247622013-11-12 15:10:21 -0800955 pr_err("Failed to execute %s (error %d)\n",
956 ramdisk_execute_command, ret);
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100957 }
958
959 /*
960 * We try each of these until one succeeds.
961 *
962 * The Bourne shell can be used instead of init if we are
963 * trying to recover a really broken machine.
964 */
965 if (execute_command) {
Michael Opdenackerba247622013-11-12 15:10:21 -0800966 ret = run_init_process(execute_command);
967 if (!ret)
Al Viroa74fb732012-10-10 21:28:25 -0400968 return 0;
Andy Lutomirski6ef45362014-12-10 15:52:19 -0800969#ifndef CONFIG_INIT_FALLBACK
970 panic("Requested init %s failed (error %d).",
971 execute_command, ret);
972#else
Michael Opdenackerba247622013-11-12 15:10:21 -0800973 pr_err("Failed to execute %s (error %d). Attempting defaults...\n",
Andy Lutomirski6ef45362014-12-10 15:52:19 -0800974 execute_command, ret);
975#endif
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100976 }
Michael Opdenackerba247622013-11-12 15:10:21 -0800977 if (!try_to_run_init_process("/sbin/init") ||
978 !try_to_run_init_process("/etc/init") ||
979 !try_to_run_init_process("/bin/init") ||
980 !try_to_run_init_process("/bin/sh"))
Al Viroa74fb732012-10-10 21:28:25 -0400981 return 0;
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100982
Michael Opdenackerba247622013-11-12 15:10:21 -0800983 panic("No working init found. Try passing init= option to kernel. "
Andreas Mohr9a85b8d2010-03-05 13:42:39 -0800984 "See Linux Documentation/init.txt for guidance.");
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100985}
986
Vineet Guptaf80b0c92012-12-21 12:25:44 +0530987static noinline void __init kernel_init_freeable(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700988{
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200989 /*
990 * Wait until kthreadd is all set-up.
991 */
992 wait_for_completion(&kthreadd_done);
Linus Torvalds31a67102012-05-21 12:52:42 -0700993
994 /* Now the scheduler is fully set up and can do blocking allocations */
995 gfp_allowed_mask = __GFP_BITS_MASK;
996
Miao Xie58568d22009-06-16 15:31:49 -0700997 /*
998 * init can allocate pages on any node
999 */
Lai Jiangshan3c466d42012-12-12 13:51:40 -08001000 set_mems_allowed(node_states[N_MEMORY]);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001 /*
1002 * init can run on any cpu.
1003 */
Rusty Russell1a2142a2009-03-30 22:05:10 -06001004 set_cpus_allowed_ptr(current, cpu_all_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001005
Cedric Le Goater9ec52092006-10-02 02:19:00 -07001006 cad_pid = task_pid(current);
1007
Andi Kleenca74a6f2008-01-30 13:33:17 +01001008 smp_prepare_cpus(setup_max_cpus);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001009
1010 do_pre_smp_initcalls();
Peter Zijlstra004417a2010-11-25 18:38:29 +01001011 lockup_detector_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001012
Linus Torvalds1da177e2005-04-16 15:20:36 -07001013 smp_init();
1014 sched_init_smp();
1015
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016 do_basic_setup();
1017
Eric W. Biederman2bd3a9972010-03-02 23:53:19 -08001018 /* Open the /dev/console on the rootfs, this should never fail */
1019 if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
Andrew Mortonea676e82013-04-29 16:18:20 -07001020 pr_err("Warning: unable to open an initial console.\n");
Eric W. Biederman2bd3a9972010-03-02 23:53:19 -08001021
1022 (void) sys_dup(0);
1023 (void) sys_dup(0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001024 /*
1025 * check if there is an early userspace init. If yes, let it do all
1026 * the work
1027 */
Olof Johanssonffdfc402005-09-06 15:17:19 -07001028
1029 if (!ramdisk_execute_command)
1030 ramdisk_execute_command = "/init";
1031
1032 if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
1033 ramdisk_execute_command = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001034 prepare_namespace();
Olof Johanssonffdfc402005-09-06 15:17:19 -07001035 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001036
1037 /*
1038 * Ok, we have completed the initial bootup, and
1039 * we're essentially up and running. Get rid of the
1040 * initmem segments and start the user-mode stuff..
Dmitry Kasatkinc9cd2ce2014-11-05 17:01:15 +02001041 *
1042 * rootfs is available now, try loading the public keys
1043 * and default modules
Linus Torvalds1da177e2005-04-16 15:20:36 -07001044 */
Tejun Heobb813f42013-01-18 14:05:56 -08001045
Dmitry Kasatkinc9cd2ce2014-11-05 17:01:15 +02001046 integrity_load_keys();
Tejun Heobb813f42013-01-18 14:05:56 -08001047 load_default_modules();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001048}