blob: e8ae1fef0908965b0c5fff7ba7ab8f043e83a980 [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
9 * Simplified starting of init: Michael A. Griffith <grif@acm.org>
10 */
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>
KAMEZAWA Hiroyuki94b6da52008-10-22 14:15:05 -070054#include <linux/page_cgroup.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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070081
82#include <asm/io.h>
83#include <asm/bugs.h>
84#include <asm/setup.h>
Andi Kleena9401992005-07-28 21:15:30 -070085#include <asm/sections.h>
Arjan van de Ven37b73c82006-01-06 00:12:01 -080086#include <asm/cacheflush.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070087
Linus Torvalds1da177e2005-04-16 15:20:36 -070088#ifdef CONFIG_X86_LOCAL_APIC
89#include <asm/smp.h>
90#endif
91
Sam Ravnborgaae5f662007-02-26 16:45:41 +010092static int kernel_init(void *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070093
94extern void init_IRQ(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070095extern void fork_init(unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -070096extern void radix_tree_init(void);
Arjan van de Ven37b73c82006-01-06 00:12:01 -080097#ifndef CONFIG_DEBUG_RODATA
98static inline void mark_rodata_ro(void) { }
99#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100
Tejun Heo2ce802f2011-01-20 12:06:35 +0100101/*
102 * Debug helper: via this flag we know that we are in 'early bootup code'
103 * where only the boot processor is running with IRQ disabled. This means
104 * two things - IRQ must not be enabled before the flag is cleared and some
105 * operations which are not allowed with IRQ disabled are allowed while the
106 * flag is set.
107 */
108bool early_boot_irqs_disabled __read_mostly;
109
Paul E. McKenneya6826042009-02-25 18:03:42 -0800110enum system_states system_state __read_mostly;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111EXPORT_SYMBOL(system_state);
112
113/*
114 * Boot command-line arguments
115 */
116#define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
117#define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
118
119extern void time_init(void);
120/* Default late time init is NULL. archs can override this later. */
Jan Beulichd2e31922009-01-06 14:41:10 -0800121void (*__initdata late_time_init)(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800123/* Untouched command line saved by arch-specific code. */
124char __initdata boot_command_line[COMMAND_LINE_SIZE];
125/* Untouched saved command line (eg. for /proc) */
126char *saved_command_line;
127/* Command line for parameter parsing */
128static char *static_command_line;
Krzysztof Mazur08746a652013-10-31 13:45:39 +1030129/* Command line for per-initcall parameter parsing */
130static char *initcall_command_line;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131
132static char *execute_command;
Olof Johanssonffdfc402005-09-06 15:17:19 -0700133static char *ramdisk_execute_command;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134
Jan Beulich8b3b2952007-07-15 23:41:07 -0700135/*
Hannes Frederic Sowac4b2c0c2013-10-19 21:48:53 +0200136 * Used to generate warnings if static_key manipulation functions are used
137 * before jump_label_init is called.
138 */
139bool static_key_initialized __read_mostly = false;
140EXPORT_SYMBOL_GPL(static_key_initialized);
141
142/*
Jan Beulich8b3b2952007-07-15 23:41:07 -0700143 * If set, this is an indication to the drivers that reset the underlying
144 * device before going ahead with the initialization otherwise driver might
145 * rely on the BIOS and skip the reset operation.
146 *
147 * This is useful if kernel is booting in an unreliable environment.
148 * For ex. kdump situaiton where previous kernel has crashed, BIOS has been
149 * skipped and devices will be in unknown state.
150 */
151unsigned int reset_devices;
152EXPORT_SYMBOL(reset_devices);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153
Vivek Goyal7e962872006-09-27 01:50:44 -0700154static int __init set_reset_devices(char *str)
155{
156 reset_devices = 1;
157 return 1;
158}
159
160__setup("reset_devices", set_reset_devices);
161
David Howellsd7627462010-08-17 23:52:56 +0100162static const char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
163const char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164static const char *panic_later, *panic_param;
165
Rusty Russell914dcaa2010-08-11 23:04:18 -0600166extern const struct obs_kernel_param __setup_start[], __setup_end[];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167
168static int __init obsolete_checksetup(char *line)
169{
Rusty Russell914dcaa2010-08-11 23:04:18 -0600170 const struct obs_kernel_param *p;
Rusty Russell33df0d12006-09-26 10:52:32 +0200171 int had_early_param = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172
173 p = __setup_start;
174 do {
175 int n = strlen(p->str);
Michal Schmidtb1e4d202011-10-10 00:03:37 +0200176 if (parameqn(line, p->str, n)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177 if (p->early) {
Rusty Russell33df0d12006-09-26 10:52:32 +0200178 /* Already done in parse_early_param?
179 * (Needs exact match on param part).
180 * Keep iterating, as we can have early
181 * params and __setups of same names 8( */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182 if (line[n] == '\0' || line[n] == '=')
Rusty Russell33df0d12006-09-26 10:52:32 +0200183 had_early_param = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184 } else if (!p->setup_func) {
Andrew Mortonea676e82013-04-29 16:18:20 -0700185 pr_warn("Parameter %s is obsolete, ignored\n",
186 p->str);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700187 return 1;
188 } else if (p->setup_func(line + n))
189 return 1;
190 }
191 p++;
192 } while (p < __setup_end);
Rusty Russell33df0d12006-09-26 10:52:32 +0200193
194 return had_early_param;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195}
196
197/*
198 * This should be approx 2 Bo*oMips to start (note initial shift), and will
199 * still work even if initially too large, it will just take slightly longer
200 */
201unsigned long loops_per_jiffy = (1<<12);
202
203EXPORT_SYMBOL(loops_per_jiffy);
204
205static int __init debug_kernel(char *str)
206{
Borislav Petkova8fe19e2014-06-04 16:11:46 -0700207 console_loglevel = CONSOLE_LOGLEVEL_DEBUG;
Yinghai Luf6f21c812008-02-08 04:21:58 -0800208 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209}
210
211static int __init quiet_kernel(char *str)
212{
Borislav Petkova8fe19e2014-06-04 16:11:46 -0700213 console_loglevel = CONSOLE_LOGLEVEL_QUIET;
Yinghai Luf6f21c812008-02-08 04:21:58 -0800214 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215}
216
Yinghai Luf6f21c812008-02-08 04:21:58 -0800217early_param("debug", debug_kernel);
218early_param("quiet", quiet_kernel);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219
220static int __init loglevel(char *str)
221{
Alexander Sverdlin808bf292011-09-21 09:51:40 +0200222 int newlevel;
223
224 /*
225 * Only update loglevel value when a correct setting was passed,
226 * to prevent blind crashes (when loglevel being set to 0) that
227 * are quite hard to debug
228 */
229 if (get_option(&str, &newlevel)) {
230 console_loglevel = newlevel;
231 return 0;
232 }
233
234 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235}
236
Yinghai Luf6f21c812008-02-08 04:21:58 -0800237early_param("loglevel", loglevel);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238
Chris Metcalfa99cd112012-04-06 12:53:50 -0400239/* Change NUL term back to "=", to make "param" the whole string. */
Greg Kroah-Hartmaneb157422012-05-02 14:33:37 -0700240static int __init repair_env_string(char *param, char *val, const char *unused)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 if (val) {
243 /* param=val or param="val"? */
244 if (val == param+strlen(param)+1)
245 val[-1] = '=';
246 else if (val == param+strlen(param)+2) {
247 val[-2] = '=';
248 memmove(val-1, val, strlen(val)+1);
249 val--;
250 } else
251 BUG();
252 }
Chris Metcalfa99cd112012-04-06 12:53:50 -0400253 return 0;
254}
255
Rusty Russell51e158c2014-04-28 11:34:33 +0930256/* Anything after -- gets handed straight to init. */
257static int __init set_init_arg(char *param, char *val, const char *unused)
258{
259 unsigned int i;
260
261 if (panic_later)
262 return 0;
263
264 repair_env_string(param, val, unused);
265
266 for (i = 0; argv_init[i]; i++) {
267 if (i == MAX_INIT_ARGS) {
268 panic_later = "init";
269 panic_param = param;
270 return 0;
271 }
272 }
273 argv_init[i] = param;
274 return 0;
275}
276
Chris Metcalfa99cd112012-04-06 12:53:50 -0400277/*
278 * Unknown boot options get handed to init, unless they look like
279 * unused parameters (modprobe will find them in /proc/cmdline).
280 */
Greg Kroah-Hartmaneb157422012-05-02 14:33:37 -0700281static int __init unknown_bootoption(char *param, char *val, const char *unused)
Chris Metcalfa99cd112012-04-06 12:53:50 -0400282{
Greg Kroah-Hartmaneb157422012-05-02 14:33:37 -0700283 repair_env_string(param, val, unused);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284
285 /* Handle obsolete-style parameters */
286 if (obsolete_checksetup(param))
287 return 0;
288
Rusty Russellf066a4f2009-12-01 14:56:44 +1030289 /* Unused module parameter. */
290 if (strchr(param, '.') && (!val || strchr(param, '.') < val))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292
293 if (panic_later)
294 return 0;
295
296 if (val) {
297 /* Environment option */
298 unsigned int i;
299 for (i = 0; envp_init[i]; i++) {
300 if (i == MAX_INIT_ENVS) {
Tetsuo Handa499a4582014-01-23 15:54:56 -0800301 panic_later = "env";
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 panic_param = param;
303 }
304 if (!strncmp(param, envp_init[i], val - param))
305 break;
306 }
307 envp_init[i] = param;
308 } else {
309 /* Command line option */
310 unsigned int i;
311 for (i = 0; argv_init[i]; i++) {
312 if (i == MAX_INIT_ARGS) {
Tetsuo Handa499a4582014-01-23 15:54:56 -0800313 panic_later = "init";
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 panic_param = param;
315 }
316 }
317 argv_init[i] = param;
318 }
319 return 0;
320}
321
322static int __init init_setup(char *str)
323{
324 unsigned int i;
325
326 execute_command = str;
327 /*
328 * In case LILO is going to boot us with default command line,
329 * it prepends "auto" before the whole cmdline which makes
330 * the shell think it should execute a script with such name.
331 * So we ignore all arguments entered _before_ init=... [MJ]
332 */
333 for (i = 1; i < MAX_INIT_ARGS; i++)
334 argv_init[i] = NULL;
335 return 1;
336}
337__setup("init=", init_setup);
338
Olof Johanssonffdfc402005-09-06 15:17:19 -0700339static int __init rdinit_setup(char *str)
340{
341 unsigned int i;
342
343 ramdisk_execute_command = str;
344 /* See "auto" comment in init_setup */
345 for (i = 1; i < MAX_INIT_ARGS; i++)
346 argv_init[i] = NULL;
347 return 1;
348}
349__setup("rdinit=", rdinit_setup);
350
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351#ifndef CONFIG_SMP
Amerigo Wang34db18a02011-03-22 16:34:06 -0700352static const unsigned int setup_max_cpus = NR_CPUS;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353#ifdef CONFIG_X86_LOCAL_APIC
354static void __init smp_init(void)
355{
356 APIC_init_uniprocessor();
357}
358#else
359#define smp_init() do { } while (0)
360#endif
361
Mike Travise0982e92008-03-26 14:23:48 -0700362static inline void setup_nr_cpu_ids(void) { }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363static inline void smp_prepare_cpus(unsigned int maxcpus) { }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364#endif
365
366/*
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800367 * We need to store the untouched command line for future reference.
368 * We also need to store the touched command line since the parameter
369 * parsing is performed in place, and we should allow a component to
370 * store reference of name/value for future reference.
371 */
372static void __init setup_command_line(char *command_line)
373{
Santosh Shilimkar098b0812014-01-21 15:50:21 -0800374 saved_command_line =
375 memblock_virt_alloc(strlen(boot_command_line) + 1, 0);
376 initcall_command_line =
377 memblock_virt_alloc(strlen(boot_command_line) + 1, 0);
378 static_command_line = memblock_virt_alloc(strlen(command_line) + 1, 0);
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800379 strcpy (saved_command_line, boot_command_line);
380 strcpy (static_command_line, command_line);
381}
382
383/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384 * We need to finalize in a non-__init function or else race conditions
385 * between the root thread and the init thread may cause start_kernel to
386 * be reaped by free_initmem before the root thread has proceeded to
387 * cpu_idle.
388 *
389 * gcc-3.4 accidentally inlines this function, so use noinline.
390 */
391
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200392static __initdata DECLARE_COMPLETION(kthreadd_done);
393
Rakib Mullickf99ebf02009-01-06 14:40:38 -0800394static noinline void __init_refok rest_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395{
Eric W. Biederman73c27992007-05-09 02:34:32 -0700396 int pid;
397
Paul E. McKenney7db905e2009-09-02 14:01:24 -0700398 rcu_scheduler_starting();
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200399 /*
Peter Zijlstra97158562010-06-30 10:37:11 +0200400 * We need to spawn init first so that it obtains pid 1, however
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200401 * the init task will end up wanting to create kthreads, which, if
402 * we schedule it before we create kthreadd, will OOPS.
403 */
Oleg Nesterov34a1b722014-06-04 16:12:19 -0700404 kernel_thread(kernel_init, NULL, CLONE_FS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 numa_default_policy();
Eric W. Biederman73c27992007-05-09 02:34:32 -0700406 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
Paul E. McKenneyd11c5632010-02-22 17:04:50 -0800407 rcu_read_lock();
Pavel Emelyanov5cd20452008-04-30 00:54:24 -0700408 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
Paul E. McKenneyd11c5632010-02-22 17:04:50 -0800409 rcu_read_unlock();
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200410 complete(&kthreadd_done);
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200411
412 /*
413 * The boot idle thread must execute schedule()
Ingo Molnar1df21052007-07-09 18:51:58 +0200414 * at least once to get things moving:
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200415 */
Ingo Molnar1df21052007-07-09 18:51:58 +0200416 init_idle_bootup_task(current);
Thomas Gleixnerbd2f5532011-03-21 12:33:18 +0100417 schedule_preempt_disabled();
Nick Piggin5bfb5d62005-11-08 21:39:01 -0800418 /* Call into cpu_idle with preempt disabled */
Thomas Gleixnera1a04ec2013-03-21 22:49:34 +0100419 cpu_startup_entry(CPUHP_ONLINE);
Ingo Molnar1df21052007-07-09 18:51:58 +0200420}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421
422/* Check for early params. */
Jim Cromie9fb48c72012-04-27 14:30:34 -0600423static int __init do_early_param(char *param, char *val, const char *unused)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424{
Rusty Russell914dcaa2010-08-11 23:04:18 -0600425 const struct obs_kernel_param *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426
427 for (p = __setup_start; p < __setup_end; p++) {
Michal Schmidtb1e4d202011-10-10 00:03:37 +0200428 if ((p->early && parameq(param, p->str)) ||
Yinghai Lu18a8bd92007-07-15 23:37:59 -0700429 (strcmp(param, "console") == 0 &&
430 strcmp(p->str, "earlycon") == 0)
431 ) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700432 if (p->setup_func(val) != 0)
Andrew Mortonea676e82013-04-29 16:18:20 -0700433 pr_warn("Malformed early option '%s'\n", param);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434 }
435 }
436 /* We accept everything at this stage. */
437 return 0;
438}
439
Magnus Damm13977092009-03-30 14:37:25 -0700440void __init parse_early_options(char *cmdline)
441{
Pawel Moll026cee02012-03-26 12:50:51 +1030442 parse_args("early options", cmdline, NULL, 0, 0, 0, do_early_param);
Magnus Damm13977092009-03-30 14:37:25 -0700443}
444
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445/* Arch code calls this early on, or if not, just before other parsing. */
446void __init parse_early_param(void)
447{
448 static __initdata int done = 0;
449 static __initdata char tmp_cmdline[COMMAND_LINE_SIZE];
450
451 if (done)
452 return;
453
454 /* All fall through to do_early_param. */
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800455 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
Magnus Damm13977092009-03-30 14:37:25 -0700456 parse_early_options(tmp_cmdline);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457 done = 1;
458}
459
460/*
461 * Activate the first processor.
462 */
463
Stas Sergeev44fd2292006-03-23 02:59:44 -0800464static void __init boot_cpu_init(void)
465{
466 int cpu = smp_processor_id();
467 /* Mark the boot cpu "present", "online" etc for SMP and UP case */
Rusty Russell915441b2009-01-01 10:12:15 +1030468 set_cpu_online(cpu, true);
Peter Zijlstra933b0612009-12-16 18:04:31 +0100469 set_cpu_active(cpu, true);
Rusty Russell915441b2009-01-01 10:12:15 +1030470 set_cpu_present(cpu, true);
471 set_cpu_possible(cpu, true);
Stas Sergeev44fd2292006-03-23 02:59:44 -0800472}
473
Benjamin Herrenschmidt839ad622008-04-18 16:56:18 +1000474void __init __weak smp_setup_processor_id(void)
Andrew Morton033ab7f2006-06-30 01:55:50 -0700475{
476}
477
David Howellseded09c2012-11-02 13:20:42 +0000478# if THREAD_SIZE >= PAGE_SIZE
Benjamin Herrenschmidt8c9843e2008-04-18 16:56:15 +1000479void __init __weak thread_info_cache_init(void)
480{
481}
David Howellseded09c2012-11-02 13:20:42 +0000482#endif
Benjamin Herrenschmidt8c9843e2008-04-18 16:56:15 +1000483
Pekka Enberg444f4782009-06-11 18:29:06 +0300484/*
485 * Set up kernel memory allocators
486 */
487static void __init mm_init(void)
488{
KAMEZAWA Hiroyukica371c02009-06-12 10:33:53 +0300489 /*
Jim Cromie7fa87ce2012-03-14 19:12:22 -0600490 * page_cgroup requires contiguous pages,
491 * bigger than MAX_ORDER unless SPARSEMEM.
KAMEZAWA Hiroyukica371c02009-06-12 10:33:53 +0300492 */
493 page_cgroup_init_flatmem();
Pekka Enberg444f4782009-06-11 18:29:06 +0300494 mem_init();
495 kmem_cache_init();
Tejun Heo099a19d2010-06-27 18:50:00 +0200496 percpu_init_late();
Kirill A. Shutemovb35f1812014-01-21 15:49:07 -0800497 pgtable_init();
Pekka Enberg444f4782009-06-11 18:29:06 +0300498 vmalloc_init();
499}
500
Andi Kleen722a9f92014-05-02 00:44:38 +0200501asmlinkage __visible void __init start_kernel(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700502{
Rusty Russell51e158c2014-04-28 11:34:33 +0930503 char * command_line, *after_dashes;
Rusty Russell914dcaa2010-08-11 23:04:18 -0600504 extern const struct kernel_param __start___param[], __stop___param[];
Andrew Morton033ab7f2006-06-30 01:55:50 -0700505
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700506 /*
507 * Need to run as early as possible, to initialize the
508 * lockdep hash:
509 */
510 lockdep_init();
Ming Lei73839c52011-11-17 13:34:31 +0800511 smp_setup_processor_id();
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700512 debug_objects_early_init();
Ingo Molnar42059422008-02-14 09:44:08 +0100513
514 /*
515 * Set up the the initial canary ASAP:
516 */
517 boot_init_stack_canary();
518
Paul Menageddbcc7e2007-10-18 23:39:30 -0700519 cgroup_init_early();
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700520
521 local_irq_disable();
Tejun Heo2ce802f2011-01-20 12:06:35 +0100522 early_boot_irqs_disabled = true;
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700523
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524/*
525 * Interrupts are still disabled. Do necessary setups, then
526 * enable them
527 */
Stas Sergeev44fd2292006-03-23 02:59:44 -0800528 boot_cpu_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529 page_address_init();
Andrew Mortonea676e82013-04-29 16:18:20 -0700530 pr_notice("%s", linux_banner);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 setup_arch(&command_line);
Linus Torvalds6345d242011-05-29 11:32:28 -0700532 mm_init_cpumask(&init_mm);
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800533 setup_command_line(command_line);
Mike Travise0982e92008-03-26 14:23:48 -0700534 setup_nr_cpu_ids();
Tejun Heod6647bd2009-07-21 17:11:50 +0900535 setup_per_cpu_areas();
Stas Sergeev44fd2292006-03-23 02:59:44 -0800536 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537
Jiang Liu9adb62a2012-07-31 16:43:28 -0700538 build_all_zonelists(NULL, NULL);
Pekka Enberg83b519e2009-06-10 19:40:04 +0300539 page_alloc_init();
540
Andrew Mortonea676e82013-04-29 16:18:20 -0700541 pr_notice("Kernel command line: %s\n", boot_command_line);
Pekka Enberg83b519e2009-06-10 19:40:04 +0300542 parse_early_param();
Rusty Russell51e158c2014-04-28 11:34:33 +0930543 after_dashes = parse_args("Booting kernel",
544 static_command_line, __start___param,
545 __stop___param - __start___param,
546 -1, -1, &unknown_bootoption);
547 if (after_dashes)
548 parse_args("Setting init args", after_dashes, NULL, 0, -1, -1,
549 set_init_arg);
Jeremy Fitzhardinge97ce2c82011-10-12 16:17:54 -0700550
551 jump_label_init();
552
Pekka Enberg83b519e2009-06-10 19:40:04 +0300553 /*
554 * These use large bootmem allocations and must precede
555 * kmem_cache_init()
556 */
Mike Travis162a7e72011-05-24 17:13:20 -0700557 setup_log_buf(0);
Pekka Enberg83b519e2009-06-10 19:40:04 +0300558 pidhash_init();
Pekka Enberg83b519e2009-06-10 19:40:04 +0300559 vfs_caches_init_early();
560 sort_main_extable();
561 trap_init();
Pekka Enberg444f4782009-06-11 18:29:06 +0300562 mm_init();
KOSAKI Motohirode03c722011-05-24 17:12:15 -0700563
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564 /*
565 * Set up the scheduler prior starting any interrupts (such as the
566 * timer interrupt). Full topology setup happens at smp_init()
567 * time - but meanwhile we still have a functioning scheduler.
568 */
569 sched_init();
570 /*
571 * Disable preemption - early bootup scheduling is extremely
572 * fragile until we cpu_idle() for the first time.
573 */
574 preempt_disable();
Steven Rostedtf91eb622013-04-29 16:18:18 -0700575 if (WARN(!irqs_disabled(), "Interrupts were enabled *very* early, fixing it\n"))
Ard van Breemenc4a68302007-01-05 16:36:19 -0800576 local_irq_disable();
Peter Zijlstra9f58a202010-11-17 23:17:35 +0100577 idr_init_cache();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578 rcu_init();
Frederic Weisbeckerd1e43fa2013-03-26 23:47:24 +0100579 tick_nohz_init();
Frederic Weisbecker65f382f2013-07-11 19:12:32 +0200580 context_tracking_init();
Yinghai Lu773e3eb2010-02-10 01:20:33 -0800581 radix_tree_init();
Yinghai Lu0b8f1ef2008-12-05 18:58:31 -0800582 /* init some links before init_ISA_irqs() */
583 early_irq_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 init_IRQ();
Thomas Gleixnerad2b1352013-03-05 15:14:05 +0100585 tick_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586 init_timers();
Thomas Gleixnerc0a31322006-01-09 20:52:32 -0800587 hrtimers_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588 softirq_init();
john stultzad596172006-06-26 00:25:06 -0700589 timekeeping_init();
john stultz88fecaa2006-07-03 00:24:04 -0700590 time_init();
Stephen Boyd38ff87f2013-06-01 23:39:40 -0700591 sched_clock_postinit();
Stephane Eranian9e630202013-04-03 14:21:33 +0200592 perf_event_init();
Heiko Carstens93e02812006-07-03 00:24:24 -0700593 profile_init();
Takao Indohd8ad7d12011-03-29 12:35:04 -0400594 call_function_init();
Steven Rostedtf91eb622013-04-29 16:18:18 -0700595 WARN(!irqs_disabled(), "Interrupts were enabled early\n");
Tejun Heo2ce802f2011-01-20 12:06:35 +0100596 early_boot_irqs_disabled = false;
Heiko Carstens93e02812006-07-03 00:24:24 -0700597 local_irq_enable();
Benjamin Herrenschmidtdcce2842009-06-18 13:24:12 +1000598
Pekka Enberg7e85ee02009-06-12 14:03:06 +0300599 kmem_cache_init_late();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600
601 /*
602 * HACK ALERT! This is early. We're enabling the console before
603 * we've done PCI setups etc, and console_init() must be aware of
604 * this. But we do want output early, in case something goes wrong.
605 */
606 console_init();
607 if (panic_later)
Tetsuo Handa499a4582014-01-23 15:54:56 -0800608 panic("Too many boot %s vars at `%s'", panic_later,
609 panic_param);
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700610
611 lockdep_info();
612
Ingo Molnar9a11b49a2006-07-03 00:24:33 -0700613 /*
614 * Need to run this when irqs are enabled, because it wants
615 * to self-test [hard/soft]-irqs on/off lock inversion bugs
616 * too:
617 */
618 locking_selftest();
619
Linus Torvalds1da177e2005-04-16 15:20:36 -0700620#ifdef CONFIG_BLK_DEV_INITRD
621 if (initrd_start && !initrd_below_start_ok &&
Geert Uytterhoevenbd673c72008-07-29 22:33:36 -0700622 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
Andrew Mortonea676e82013-04-29 16:18:20 -0700623 pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n",
Geert Uytterhoevenbd673c72008-07-29 22:33:36 -0700624 page_to_pfn(virt_to_page((void *)initrd_start)),
625 min_low_pfn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700626 initrd_start = 0;
627 }
628#endif
KAMEZAWA Hiroyuki94b6da52008-10-22 14:15:05 -0700629 page_cgroup_init();
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700630 debug_objects_mem_init();
Catalin Marinas9b090f22011-05-19 16:25:30 +0100631 kmemleak_init();
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700632 setup_per_cpu_pageset();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633 numa_policy_init();
634 if (late_time_init)
635 late_time_init();
Thomas Gleixnerfa84e9e2009-08-21 22:01:12 +0200636 sched_clock_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637 calibrate_delay();
638 pidmap_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639 anon_vma_init();
Rafael J. Wysockic4e1acb2014-03-13 00:22:58 +0100640 acpi_early_init();
Linus Torvalds11520e52012-12-15 15:15:24 -0800641#ifdef CONFIG_X86
Matt Fleming83e68182012-11-14 09:42:35 +0000642 if (efi_enabled(EFI_RUNTIME_SERVICES))
Linus Torvalds11520e52012-12-15 15:15:24 -0800643 efi_enter_virtual_mode();
644#endif
H. Peter Anvin197725d2014-05-04 10:00:49 -0700645#ifdef CONFIG_X86_ESPFIX64
H. Peter Anvin3891a042014-04-29 16:46:09 -0700646 /* Should be run before the first non-init thread is created */
647 init_espfix_bsp();
648#endif
Benjamin Herrenschmidt8c9843e2008-04-18 16:56:15 +1000649 thread_info_cache_init();
David Howellsd84f4f92008-11-14 10:39:23 +1100650 cred_init();
Jan Beulich44813742009-09-21 17:03:05 -0700651 fork_init(totalram_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652 proc_caches_init();
653 buffer_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654 key_init();
655 security_init();
Jason Wessel0b4b3822010-05-20 21:04:29 -0500656 dbg_late_init();
Jan Beulich44813742009-09-21 17:03:05 -0700657 vfs_caches_init(totalram_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658 signals_init();
659 /* rootfs populating might need page-writeback */
660 page_writeback_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661 proc_root_init();
Paul Menageddbcc7e2007-10-18 23:39:30 -0700662 cgroup_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 cpuset_init();
Shailabh Nagarc7572492006-07-14 00:24:40 -0700664 taskstats_init_early();
Shailabh Nagarca74e922006-07-14 00:24:36 -0700665 delayacct_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666
667 check_bugs();
668
Feng Tang6ae69962009-08-14 15:13:46 -0400669 sfi_init_late();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700670
Matt Fleming83e68182012-11-14 09:42:35 +0000671 if (efi_enabled(EFI_RUNTIME_SERVICES)) {
Josh Triplett2223af382012-09-28 17:57:05 -0700672 efi_late_init();
Josh Triplett78510792012-09-28 17:55:44 -0700673 efi_free_boot_services();
Josh Triplett2223af382012-09-28 17:57:05 -0700674 }
Josh Triplett78510792012-09-28 17:55:44 -0700675
Steven Rostedt68bf21a2008-08-14 15:45:08 -0400676 ftrace_init();
677
Linus Torvalds1da177e2005-04-16 15:20:36 -0700678 /* Do the rest non-__init'ed, we're now alive */
679 rest_init();
680}
681
Peter Oberparleiterb99b87f72009-06-17 16:28:03 -0700682/* Call all constructor functions linked into the kernel. */
683static void __init do_ctors(void)
684{
685#ifdef CONFIG_CONSTRUCTORS
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800686 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start;
Peter Oberparleiterb99b87f72009-06-17 16:28:03 -0700687
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800688 for (; fn < (ctor_fn_t *) __ctors_end; fn++)
689 (*fn)();
Peter Oberparleiterb99b87f72009-06-17 16:28:03 -0700690#endif
691}
692
Rusty Russell2329abf2012-01-13 09:32:18 +1030693bool initcall_debug;
Rusty Russelld0ea3d72008-10-22 10:00:23 -0500694core_param(initcall_debug, initcall_debug, bool, 0644);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700695
Prarit Bhargava7b0b73d2014-06-04 16:12:17 -0700696#ifdef CONFIG_KALLSYMS
697struct blacklist_entry {
698 struct list_head next;
699 char *buf;
700};
701
702static __initdata_or_module LIST_HEAD(blacklisted_initcalls);
703
704static int __init initcall_blacklist(char *str)
705{
706 char *str_entry;
707 struct blacklist_entry *entry;
708
709 /* str argument is a comma-separated list of functions */
710 do {
711 str_entry = strsep(&str, ",");
712 if (str_entry) {
713 pr_debug("blacklisting initcall %s\n", str_entry);
714 entry = alloc_bootmem(sizeof(*entry));
715 entry->buf = alloc_bootmem(strlen(str_entry) + 1);
716 strcpy(entry->buf, str_entry);
717 list_add(&entry->next, &blacklisted_initcalls);
718 }
719 } while (str_entry);
720
721 return 0;
722}
723
724static bool __init_or_module initcall_blacklisted(initcall_t fn)
725{
726 struct list_head *tmp;
727 struct blacklist_entry *entry;
728 char *fn_name;
729
730 fn_name = kasprintf(GFP_KERNEL, "%pf", fn);
731 if (!fn_name)
732 return false;
733
734 list_for_each(tmp, &blacklisted_initcalls) {
735 entry = list_entry(tmp, struct blacklist_entry, next);
736 if (!strcmp(fn_name, entry->buf)) {
737 pr_debug("initcall %s blacklisted\n", fn_name);
738 kfree(fn_name);
739 return true;
740 }
741 }
742
743 kfree(fn_name);
744 return false;
745}
746#else
747static int __init initcall_blacklist(char *str)
748{
749 pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n");
750 return 0;
751}
752
753static bool __init_or_module initcall_blacklisted(initcall_t fn)
754{
755 return false;
756}
757#endif
758__setup("initcall_blacklist=", initcall_blacklist);
759
Kevin Winchestere4461272010-08-09 17:20:32 -0700760static int __init_or_module do_one_initcall_debug(initcall_t fn)
Linus Torvaldse0df1542008-05-15 18:14:01 -0700761{
Frederic Weisbecker74239072008-11-11 23:24:42 +0100762 ktime_t calltime, delta, rettime;
Américo Wang30dbb20e2010-05-26 18:57:53 +0800763 unsigned long long duration;
764 int ret;
Linus Torvaldse0df1542008-05-15 18:14:01 -0700765
Andrew Mortond62cf812014-06-04 16:12:16 -0700766 printk(KERN_DEBUG "calling %pF @ %i\n", fn, task_pid_nr(current));
Kevin Winchester22c5c032010-08-09 17:20:32 -0700767 calltime = ktime_get();
Américo Wang30dbb20e2010-05-26 18:57:53 +0800768 ret = fn();
Kevin Winchester22c5c032010-08-09 17:20:32 -0700769 rettime = ktime_get();
770 delta = ktime_sub(rettime, calltime);
771 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
Andrew Mortond62cf812014-06-04 16:12:16 -0700772 printk(KERN_DEBUG "initcall %pF returned %d after %lld usecs\n",
Andrew Mortonea676e82013-04-29 16:18:20 -0700773 fn, ret, duration);
Linus Torvaldse0df1542008-05-15 18:14:01 -0700774
Kevin Winchester22c5c032010-08-09 17:20:32 -0700775 return ret;
776}
777
Kevin Winchestere4461272010-08-09 17:20:32 -0700778int __init_or_module do_one_initcall(initcall_t fn)
Kevin Winchester22c5c032010-08-09 17:20:32 -0700779{
780 int count = preempt_count();
781 int ret;
Steven Rostedtff1c8fa2013-07-03 15:05:37 -0700782 char msgbuf[64];
Kevin Winchester22c5c032010-08-09 17:20:32 -0700783
Prarit Bhargava7b0b73d2014-06-04 16:12:17 -0700784 if (initcall_blacklisted(fn))
785 return -EPERM;
786
Kevin Winchester22c5c032010-08-09 17:20:32 -0700787 if (initcall_debug)
788 ret = do_one_initcall_debug(fn);
789 else
790 ret = fn();
Linus Torvaldse0df1542008-05-15 18:14:01 -0700791
792 msgbuf[0] = 0;
793
Linus Torvaldse0df1542008-05-15 18:14:01 -0700794 if (preempt_count() != count) {
Steven Rostedtbf5d7702013-05-01 13:35:51 -0400795 sprintf(msgbuf, "preemption imbalance ");
Peter Zijlstra4a2b4b22013-08-14 14:55:24 +0200796 preempt_count_set(count);
Linus Torvaldse0df1542008-05-15 18:14:01 -0700797 }
798 if (irqs_disabled()) {
Cyrill Gorcunova76bfd02008-05-15 13:52:41 -0700799 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf));
Linus Torvaldse0df1542008-05-15 18:14:01 -0700800 local_irq_enable();
801 }
Steven Rostedtf91eb622013-04-29 16:18:18 -0700802 WARN(msgbuf[0], "initcall %pF returned with %s\n", fn, msgbuf);
Arjan van de Ven59f94152008-07-30 12:49:02 -0700803
Américo Wang30dbb20e2010-05-26 18:57:53 +0800804 return ret;
Linus Torvaldse0df1542008-05-15 18:14:01 -0700805}
806
807
Pawel Moll026cee02012-03-26 12:50:51 +1030808extern initcall_t __initcall_start[];
809extern initcall_t __initcall0_start[];
810extern initcall_t __initcall1_start[];
811extern initcall_t __initcall2_start[];
812extern initcall_t __initcall3_start[];
813extern initcall_t __initcall4_start[];
814extern initcall_t __initcall5_start[];
815extern initcall_t __initcall6_start[];
816extern initcall_t __initcall7_start[];
817extern initcall_t __initcall_end[];
818
819static initcall_t *initcall_levels[] __initdata = {
820 __initcall0_start,
821 __initcall1_start,
822 __initcall2_start,
823 __initcall3_start,
824 __initcall4_start,
825 __initcall5_start,
826 __initcall6_start,
827 __initcall7_start,
828 __initcall_end,
829};
830
Jim Cromie96263d22012-06-14 16:00:59 -0600831/* Keep these in sync with initcalls in include/linux/init.h */
Pawel Moll026cee02012-03-26 12:50:51 +1030832static char *initcall_level_names[] __initdata = {
Jim Cromie9fb48c72012-04-27 14:30:34 -0600833 "early",
834 "core",
835 "postcore",
836 "arch",
837 "subsys",
838 "fs",
839 "device",
840 "late",
Pawel Moll026cee02012-03-26 12:50:51 +1030841};
842
Pawel Moll026cee02012-03-26 12:50:51 +1030843static void __init do_initcall_level(int level)
844{
845 extern const struct kernel_param __start___param[], __stop___param[];
846 initcall_t *fn;
847
Krzysztof Mazur08746a652013-10-31 13:45:39 +1030848 strcpy(initcall_command_line, saved_command_line);
Pawel Moll026cee02012-03-26 12:50:51 +1030849 parse_args(initcall_level_names[level],
Krzysztof Mazur08746a652013-10-31 13:45:39 +1030850 initcall_command_line, __start___param,
Pawel Moll026cee02012-03-26 12:50:51 +1030851 __stop___param - __start___param,
852 level, level,
Greg Kroah-Hartmaneb157422012-05-02 14:33:37 -0700853 &repair_env_string);
Pawel Moll026cee02012-03-26 12:50:51 +1030854
855 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++)
856 do_one_initcall(*fn);
857}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858
859static void __init do_initcalls(void)
860{
Pawel Moll026cee02012-03-26 12:50:51 +1030861 int level;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862
Borislav Petkov19efb722012-06-01 18:56:00 +0200863 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++)
Pawel Moll026cee02012-03-26 12:50:51 +1030864 do_initcall_level(level);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700865}
866
867/*
868 * Ok, the machine is now initialized. None of the devices
869 * have been touched yet, but the CPU subsystem is up and
870 * running, and memory and process management works.
871 *
872 * Now we can finally start doing some real work..
873 */
874static void __init do_basic_setup(void)
875{
Lai Jiangshan759ee092009-03-25 17:06:30 +0800876 cpuset_init_smp();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877 usermodehelper_init();
Hugh Dickins41ffe5d2011-08-03 16:21:21 -0700878 shmem_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879 driver_init();
Eric W. Biedermanb04c3af2007-02-14 00:33:57 -0800880 init_irq_proc();
Peter Oberparleiterb99b87f72009-06-17 16:28:03 -0700881 do_ctors();
Linus Torvaldsd5767c52011-09-28 10:23:44 -0700882 usermodehelper_enable();
wangyanqingb0f84372011-09-29 15:09:40 +0800883 do_initcalls();
Theodore Ts'o47d06e52013-09-10 10:52:35 -0400884 random_int_secret_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700885}
886
Eduard - Gabriel Munteanu7babe8d2008-07-25 19:45:11 -0700887static void __init do_pre_smp_initcalls(void)
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700888{
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800889 initcall_t *fn;
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700890
Pawel Moll026cee02012-03-26 12:50:51 +1030891 for (fn = __initcall_start; fn < __initcall0_start; fn++)
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800892 do_one_initcall(*fn);
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700893}
894
Tejun Heobb813f42013-01-18 14:05:56 -0800895/*
896 * This function requests modules which should be loaded by default and is
897 * called twice right after initrd is mounted and right before init is
898 * exec'd. If such modules are on either initrd or rootfs, they will be
899 * loaded before control is passed to userland.
900 */
901void __init load_default_modules(void)
902{
903 load_default_elevator_module();
904}
905
Al Viroa74fb732012-10-10 21:28:25 -0400906static int run_init_process(const char *init_filename)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700907{
908 argv_init[0] = init_filename;
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -0800909 return do_execve(getname_kernel(init_filename),
Al Viroae903ca2012-12-14 12:44:11 -0500910 (const char __user *const __user *)argv_init,
911 (const char __user *const __user *)envp_init);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912}
913
Michael Opdenackerba247622013-11-12 15:10:21 -0800914static int try_to_run_init_process(const char *init_filename)
915{
916 int ret;
917
918 ret = run_init_process(init_filename);
919
920 if (ret && ret != -ENOENT) {
921 pr_err("Starting init: %s exists but couldn't execute it (error %d)\n",
922 init_filename, ret);
923 }
924
925 return ret;
926}
927
Vineet Guptaf80b0c92012-12-21 12:25:44 +0530928static noinline void __init kernel_init_freeable(void);
Al Virod6b21232012-10-10 19:57:26 -0400929
930static int __ref kernel_init(void *unused)
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100931{
Michael Opdenackerba247622013-11-12 15:10:21 -0800932 int ret;
933
Al Virod6b21232012-10-10 19:57:26 -0400934 kernel_init_freeable();
Arjan van de Ven22a9d642009-01-07 08:45:46 -0800935 /* need to finish all async __init code before freeing the memory */
936 async_synchronize_full();
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100937 free_initmem();
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100938 mark_rodata_ro();
939 system_state = SYSTEM_RUNNING;
940 numa_default_policy();
941
Al Viro4a9d4b02012-06-24 09:56:45 +0400942 flush_delayed_fput();
Oleg Nesterovfae5fa42008-04-30 00:53:03 -0700943
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100944 if (ramdisk_execute_command) {
Michael Opdenackerba247622013-11-12 15:10:21 -0800945 ret = run_init_process(ramdisk_execute_command);
946 if (!ret)
Al Viroa74fb732012-10-10 21:28:25 -0400947 return 0;
Michael Opdenackerba247622013-11-12 15:10:21 -0800948 pr_err("Failed to execute %s (error %d)\n",
949 ramdisk_execute_command, ret);
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100950 }
951
952 /*
953 * We try each of these until one succeeds.
954 *
955 * The Bourne shell can be used instead of init if we are
956 * trying to recover a really broken machine.
957 */
958 if (execute_command) {
Michael Opdenackerba247622013-11-12 15:10:21 -0800959 ret = run_init_process(execute_command);
960 if (!ret)
Al Viroa74fb732012-10-10 21:28:25 -0400961 return 0;
Michael Opdenackerba247622013-11-12 15:10:21 -0800962 pr_err("Failed to execute %s (error %d). Attempting defaults...\n",
963 execute_command, ret);
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100964 }
Michael Opdenackerba247622013-11-12 15:10:21 -0800965 if (!try_to_run_init_process("/sbin/init") ||
966 !try_to_run_init_process("/etc/init") ||
967 !try_to_run_init_process("/bin/init") ||
968 !try_to_run_init_process("/bin/sh"))
Al Viroa74fb732012-10-10 21:28:25 -0400969 return 0;
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100970
Michael Opdenackerba247622013-11-12 15:10:21 -0800971 panic("No working init found. Try passing init= option to kernel. "
Andreas Mohr9a85b8d2010-03-05 13:42:39 -0800972 "See Linux Documentation/init.txt for guidance.");
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100973}
974
Vineet Guptaf80b0c92012-12-21 12:25:44 +0530975static noinline void __init kernel_init_freeable(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976{
Peter Zijlstrab433c3d2010-06-28 16:51:01 +0200977 /*
978 * Wait until kthreadd is all set-up.
979 */
980 wait_for_completion(&kthreadd_done);
Linus Torvalds31a67102012-05-21 12:52:42 -0700981
982 /* Now the scheduler is fully set up and can do blocking allocations */
983 gfp_allowed_mask = __GFP_BITS_MASK;
984
Miao Xie58568d22009-06-16 15:31:49 -0700985 /*
986 * init can allocate pages on any node
987 */
Lai Jiangshan3c466d42012-12-12 13:51:40 -0800988 set_mems_allowed(node_states[N_MEMORY]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700989 /*
990 * init can run on any cpu.
991 */
Rusty Russell1a2142a2009-03-30 22:05:10 -0600992 set_cpus_allowed_ptr(current, cpu_all_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700993
Cedric Le Goater9ec52092006-10-02 02:19:00 -0700994 cad_pid = task_pid(current);
995
Andi Kleenca74a6f2008-01-30 13:33:17 +0100996 smp_prepare_cpus(setup_max_cpus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700997
998 do_pre_smp_initcalls();
Peter Zijlstra004417a2010-11-25 18:38:29 +0100999 lockup_detector_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001000
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001 smp_init();
1002 sched_init_smp();
1003
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004 do_basic_setup();
1005
Eric W. Biederman2bd3a9972010-03-02 23:53:19 -08001006 /* Open the /dev/console on the rootfs, this should never fail */
1007 if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
Andrew Mortonea676e82013-04-29 16:18:20 -07001008 pr_err("Warning: unable to open an initial console.\n");
Eric W. Biederman2bd3a9972010-03-02 23:53:19 -08001009
1010 (void) sys_dup(0);
1011 (void) sys_dup(0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001012 /*
1013 * check if there is an early userspace init. If yes, let it do all
1014 * the work
1015 */
Olof Johanssonffdfc402005-09-06 15:17:19 -07001016
1017 if (!ramdisk_execute_command)
1018 ramdisk_execute_command = "/init";
1019
1020 if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
1021 ramdisk_execute_command = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001022 prepare_namespace();
Olof Johanssonffdfc402005-09-06 15:17:19 -07001023 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001024
1025 /*
1026 * Ok, we have completed the initial bootup, and
1027 * we're essentially up and running. Get rid of the
1028 * initmem segments and start the user-mode stuff..
1029 */
Tejun Heobb813f42013-01-18 14:05:56 -08001030
1031 /* rootfs is available now, try loading default modules */
1032 load_default_modules();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001033}