blob: a1ab78ceb4b62abf17551bc990a3298d1c95a320 [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
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/types.h>
13#include <linux/module.h>
14#include <linux/proc_fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#include <linux/kernel.h>
16#include <linux/syscalls.h>
Ingo Molnar9b5609fd2008-02-14 09:41:09 +010017#include <linux/stackprotector.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <linux/string.h>
19#include <linux/ctype.h>
20#include <linux/delay.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <linux/ioport.h>
22#include <linux/init.h>
23#include <linux/smp_lock.h>
24#include <linux/initrd.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070025#include <linux/bootmem.h>
Len Brown4a7a16d2009-06-12 20:42:08 -040026#include <linux/acpi.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <linux/tty.h>
28#include <linux/gfp.h>
29#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/workqueue.h>
37#include <linux/profile.h>
38#include <linux/rcupdate.h>
39#include <linux/moduleparam.h>
40#include <linux/kallsyms.h>
41#include <linux/writeback.h>
42#include <linux/cpu.h>
43#include <linux/cpuset.h>
Paul Menageddbcc7e2007-10-18 23:39:30 -070044#include <linux/cgroup.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070045#include <linux/efi.h>
Thomas Gleixner906568c2007-02-16 01:28:01 -080046#include <linux/tick.h>
Andrew Morton6168a702007-02-17 21:22:39 -080047#include <linux/interrupt.h>
Shailabh Nagarc7572492006-07-14 00:24:40 -070048#include <linux/taskstats_kern.h>
Shailabh Nagarca74e922006-07-14 00:24:36 -070049#include <linux/delayacct.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070050#include <linux/unistd.h>
51#include <linux/rmap.h>
52#include <linux/mempolicy.h>
53#include <linux/key.h>
Adrian Bunkb6cd0b72006-06-27 02:53:54 -070054#include <linux/buffer_head.h>
KAMEZAWA Hiroyuki94b6da52008-10-22 14:15:05 -070055#include <linux/page_cgroup.h>
Ingo Molnar9a11b49a2006-07-03 00:24:33 -070056#include <linux/debug_locks.h>
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -070057#include <linux/debugobjects.h>
Ingo Molnarfbb9ce92006-07-03 00:24:50 -070058#include <linux/lockdep.h>
Catalin Marinas3c7b4e62009-06-11 13:22:39 +010059#include <linux/kmemleak.h>
Sukadev Bhattiprolu84d73782006-12-08 02:38:01 -080060#include <linux/pid_namespace.h>
Adrian Bunk1f217822006-12-19 13:01:28 -080061#include <linux/device.h>
Eric W. Biederman73c27992007-05-09 02:34:32 -070062#include <linux/kthread.h>
Adrian Bunke6fe6642007-11-09 22:39:39 +010063#include <linux/sched.h>
Adrian Bunka1c9eea2008-02-06 01:36:44 -080064#include <linux/signal.h>
Akinobu Mita199f0ca2008-04-29 01:03:13 -070065#include <linux/idr.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>
Zhaolei02af61b2009-04-10 14:26:18 +080069#include <linux/kmemtrace.h>
Feng Tang6ae69962009-08-14 15:13:46 -040070#include <linux/sfi.h>
Kay Sievers2b2af542009-04-30 15:23:42 +020071#include <linux/shmem_fs.h>
Frederic Weisbecker3f5ec132008-11-11 23:21:31 +010072#include <trace/boot.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
74#include <asm/io.h>
75#include <asm/bugs.h>
76#include <asm/setup.h>
Andi Kleena9401992005-07-28 21:15:30 -070077#include <asm/sections.h>
Arjan van de Ven37b73c82006-01-06 00:12:01 -080078#include <asm/cacheflush.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
Linus Torvalds1da177e2005-04-16 15:20:36 -070080#ifdef CONFIG_X86_LOCAL_APIC
81#include <asm/smp.h>
82#endif
83
Sam Ravnborgaae5f662007-02-26 16:45:41 +010084static int kernel_init(void *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070085
86extern void init_IRQ(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070087extern void fork_init(unsigned long);
88extern void mca_init(void);
89extern void sbus_init(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070090extern void prio_tree_init(void);
91extern void radix_tree_init(void);
92extern void free_initmem(void);
Arjan van de Ven37b73c82006-01-06 00:12:01 -080093#ifndef CONFIG_DEBUG_RODATA
94static inline void mark_rodata_ro(void) { }
95#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070096
97#ifdef CONFIG_TC
98extern void tc_init(void);
99#endif
100
Paul E. McKenneya6826042009-02-25 18:03:42 -0800101enum system_states system_state __read_mostly;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102EXPORT_SYMBOL(system_state);
103
104/*
105 * Boot command-line arguments
106 */
107#define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
108#define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
109
110extern void time_init(void);
111/* Default late time init is NULL. archs can override this later. */
Jan Beulichd2e31922009-01-06 14:41:10 -0800112void (*__initdata late_time_init)(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113extern void softirq_init(void);
114
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800115/* Untouched command line saved by arch-specific code. */
116char __initdata boot_command_line[COMMAND_LINE_SIZE];
117/* Untouched saved command line (eg. for /proc) */
118char *saved_command_line;
119/* Command line for parameter parsing */
120static char *static_command_line;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121
122static char *execute_command;
Olof Johanssonffdfc402005-09-06 15:17:19 -0700123static char *ramdisk_execute_command;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124
Jan Beulich8b3b2952007-07-15 23:41:07 -0700125#ifdef CONFIG_SMP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126/* Setup configured maximum number of CPUs to activate */
Andi Kleenca74a6f2008-01-30 13:33:17 +0100127unsigned int __initdata setup_max_cpus = NR_CPUS;
Vivek Goyal7e962872006-09-27 01:50:44 -0700128
129/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130 * Setup routine for controlling SMP activation
131 *
132 * Command-line option of "nosmp" or "maxcpus=0" will disable SMP
133 * activation entirely (the MPS table probe still happens, though).
134 *
135 * Command-line option of "maxcpus=<NUM>", where <NUM> is an integer
136 * greater than 0, limits the maximum number of CPUs activated in
137 * SMP mode to <NUM>.
138 */
Ingo Molnar65a4e572009-01-31 03:36:17 +0100139
140void __weak arch_disable_smp_support(void) { }
Len Brown61ec7562007-08-16 03:34:22 -0400141
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142static int __init nosmp(char *str)
143{
Andi Kleenca74a6f2008-01-30 13:33:17 +0100144 setup_max_cpus = 0;
Ingo Molnar65a4e572009-01-31 03:36:17 +0100145 arch_disable_smp_support();
146
Jan Beulich8b3b2952007-07-15 23:41:07 -0700147 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148}
149
Jan Beulich8b3b2952007-07-15 23:41:07 -0700150early_param("nosmp", nosmp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151
Yinghai Lu2b633e32010-02-10 01:20:37 -0800152/* this is hard limit */
153static int __init nrcpus(char *str)
154{
155 int nr_cpus;
156
157 get_option(&str, &nr_cpus);
158 if (nr_cpus > 0 && nr_cpus < nr_cpu_ids)
159 nr_cpu_ids = nr_cpus;
160
161 return 0;
162}
163
164early_param("nr_cpus", nrcpus);
165
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166static int __init maxcpus(char *str)
167{
Andi Kleenca74a6f2008-01-30 13:33:17 +0100168 get_option(&str, &setup_max_cpus);
169 if (setup_max_cpus == 0)
Ingo Molnar65a4e572009-01-31 03:36:17 +0100170 arch_disable_smp_support();
Len Brown61ec7562007-08-16 03:34:22 -0400171
172 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173}
174
Hugh Dickins81340972007-08-27 16:02:12 +0100175early_param("maxcpus", maxcpus);
Jan Beulich8b3b2952007-07-15 23:41:07 -0700176#else
H Hartley Sweeten7463e632010-03-05 13:42:46 -0800177static const unsigned int setup_max_cpus = NR_CPUS;
Jan Beulich8b3b2952007-07-15 23:41:07 -0700178#endif
179
180/*
181 * If set, this is an indication to the drivers that reset the underlying
182 * device before going ahead with the initialization otherwise driver might
183 * rely on the BIOS and skip the reset operation.
184 *
185 * This is useful if kernel is booting in an unreliable environment.
186 * For ex. kdump situaiton where previous kernel has crashed, BIOS has been
187 * skipped and devices will be in unknown state.
188 */
189unsigned int reset_devices;
190EXPORT_SYMBOL(reset_devices);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191
Vivek Goyal7e962872006-09-27 01:50:44 -0700192static int __init set_reset_devices(char *str)
193{
194 reset_devices = 1;
195 return 1;
196}
197
198__setup("reset_devices", set_reset_devices);
199
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200static char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
201char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
202static const char *panic_later, *panic_param;
203
204extern struct obs_kernel_param __setup_start[], __setup_end[];
205
206static int __init obsolete_checksetup(char *line)
207{
208 struct obs_kernel_param *p;
Rusty Russell33df0d12006-09-26 10:52:32 +0200209 int had_early_param = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210
211 p = __setup_start;
212 do {
213 int n = strlen(p->str);
214 if (!strncmp(line, p->str, n)) {
215 if (p->early) {
Rusty Russell33df0d12006-09-26 10:52:32 +0200216 /* Already done in parse_early_param?
217 * (Needs exact match on param part).
218 * Keep iterating, as we can have early
219 * params and __setups of same names 8( */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220 if (line[n] == '\0' || line[n] == '=')
Rusty Russell33df0d12006-09-26 10:52:32 +0200221 had_early_param = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 } else if (!p->setup_func) {
223 printk(KERN_WARNING "Parameter %s is obsolete,"
224 " ignored\n", p->str);
225 return 1;
226 } else if (p->setup_func(line + n))
227 return 1;
228 }
229 p++;
230 } while (p < __setup_end);
Rusty Russell33df0d12006-09-26 10:52:32 +0200231
232 return had_early_param;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233}
234
235/*
236 * This should be approx 2 Bo*oMips to start (note initial shift), and will
237 * still work even if initially too large, it will just take slightly longer
238 */
239unsigned long loops_per_jiffy = (1<<12);
240
241EXPORT_SYMBOL(loops_per_jiffy);
242
243static int __init debug_kernel(char *str)
244{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245 console_loglevel = 10;
Yinghai Luf6f21c812008-02-08 04:21:58 -0800246 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247}
248
249static int __init quiet_kernel(char *str)
250{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251 console_loglevel = 4;
Yinghai Luf6f21c812008-02-08 04:21:58 -0800252 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253}
254
Yinghai Luf6f21c812008-02-08 04:21:58 -0800255early_param("debug", debug_kernel);
256early_param("quiet", quiet_kernel);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257
258static int __init loglevel(char *str)
259{
260 get_option(&str, &console_loglevel);
Alex Riesend9d4fcf2008-03-04 14:28:31 -0800261 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262}
263
Yinghai Luf6f21c812008-02-08 04:21:58 -0800264early_param("loglevel", loglevel);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265
266/*
267 * Unknown boot options get handed to init, unless they look like
Rusty Russellf066a4f2009-12-01 14:56:44 +1030268 * unused parameters (modprobe will find them in /proc/cmdline).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 */
270static int __init unknown_bootoption(char *param, char *val)
271{
272 /* Change NUL term back to "=", to make "param" the whole string. */
273 if (val) {
274 /* param=val or param="val"? */
275 if (val == param+strlen(param)+1)
276 val[-1] = '=';
277 else if (val == param+strlen(param)+2) {
278 val[-2] = '=';
279 memmove(val-1, val, strlen(val)+1);
280 val--;
281 } else
282 BUG();
283 }
284
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) {
301 panic_later = "Too many boot env vars at `%s'";
302 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) {
313 panic_later = "Too many boot init vars at `%s'";
314 panic_param = param;
315 }
316 }
317 argv_init[i] = param;
318 }
319 return 0;
320}
321
Ingo Molnar12d6f212008-01-30 13:33:58 +0100322#ifdef CONFIG_DEBUG_PAGEALLOC
323int __read_mostly debug_pagealloc_enabled = 0;
324#endif
325
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326static int __init init_setup(char *str)
327{
328 unsigned int i;
329
330 execute_command = str;
331 /*
332 * In case LILO is going to boot us with default command line,
333 * it prepends "auto" before the whole cmdline which makes
334 * the shell think it should execute a script with such name.
335 * So we ignore all arguments entered _before_ init=... [MJ]
336 */
337 for (i = 1; i < MAX_INIT_ARGS; i++)
338 argv_init[i] = NULL;
339 return 1;
340}
341__setup("init=", init_setup);
342
Olof Johanssonffdfc402005-09-06 15:17:19 -0700343static int __init rdinit_setup(char *str)
344{
345 unsigned int i;
346
347 ramdisk_execute_command = str;
348 /* See "auto" comment in init_setup */
349 for (i = 1; i < MAX_INIT_ARGS; i++)
350 argv_init[i] = NULL;
351 return 1;
352}
353__setup("rdinit=", rdinit_setup);
354
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355#ifndef CONFIG_SMP
356
357#ifdef CONFIG_X86_LOCAL_APIC
358static void __init smp_init(void)
359{
360 APIC_init_uniprocessor();
361}
362#else
363#define smp_init() do { } while (0)
364#endif
365
Mike Travise0982e92008-03-26 14:23:48 -0700366static inline void setup_nr_cpu_ids(void) { }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367static inline void smp_prepare_cpus(unsigned int maxcpus) { }
368
369#else
370
Mike Travise0982e92008-03-26 14:23:48 -0700371/* Setup number of possible processor ids */
372int nr_cpu_ids __read_mostly = NR_CPUS;
373EXPORT_SYMBOL(nr_cpu_ids);
374
375/* An arch may set nr_cpu_ids earlier if needed, so this would be redundant */
376static void __init setup_nr_cpu_ids(void)
377{
Rusty Russelle0c0ba72009-01-01 10:12:19 +1030378 nr_cpu_ids = find_last_bit(cpumask_bits(cpu_possible_mask),NR_CPUS) + 1;
Mike Travise0982e92008-03-26 14:23:48 -0700379}
380
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381/* Called by boot processor to activate the rest. */
382static void __init smp_init(void)
383{
Christoph Lameter53b8a312007-02-20 13:57:51 -0800384 unsigned int cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385
386 /* FIXME: This should be done in userspace --RR */
Christoph Lameter53b8a312007-02-20 13:57:51 -0800387 for_each_present_cpu(cpu) {
Andi Kleenca74a6f2008-01-30 13:33:17 +0100388 if (num_online_cpus() >= setup_max_cpus)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389 break;
Christoph Lameter53b8a312007-02-20 13:57:51 -0800390 if (!cpu_online(cpu))
391 cpu_up(cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392 }
393
394 /* Any cleanup work */
395 printk(KERN_INFO "Brought up %ld CPUs\n", (long)num_online_cpus());
Andi Kleenca74a6f2008-01-30 13:33:17 +0100396 smp_cpus_done(setup_max_cpus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397}
398
399#endif
400
401/*
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800402 * We need to store the untouched command line for future reference.
403 * We also need to store the touched command line since the parameter
404 * parsing is performed in place, and we should allow a component to
405 * store reference of name/value for future reference.
406 */
407static void __init setup_command_line(char *command_line)
408{
409 saved_command_line = alloc_bootmem(strlen (boot_command_line)+1);
410 static_command_line = alloc_bootmem(strlen (command_line)+1);
411 strcpy (saved_command_line, boot_command_line);
412 strcpy (static_command_line, command_line);
413}
414
415/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416 * We need to finalize in a non-__init function or else race conditions
417 * between the root thread and the init thread may cause start_kernel to
418 * be reaped by free_initmem before the root thread has proceeded to
419 * cpu_idle.
420 *
421 * gcc-3.4 accidentally inlines this function, so use noinline.
422 */
423
Rakib Mullickf99ebf02009-01-06 14:40:38 -0800424static noinline void __init_refok rest_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425 __releases(kernel_lock)
426{
Eric W. Biederman73c27992007-05-09 02:34:32 -0700427 int pid;
428
Paul E. McKenney7db905e2009-09-02 14:01:24 -0700429 rcu_scheduler_starting();
Sam Ravnborgaae5f662007-02-26 16:45:41 +0100430 kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431 numa_default_policy();
Eric W. Biederman73c27992007-05-09 02:34:32 -0700432 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
Paul E. McKenneyd11c5632010-02-22 17:04:50 -0800433 rcu_read_lock();
Pavel Emelyanov5cd20452008-04-30 00:54:24 -0700434 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
Paul E. McKenneyd11c5632010-02-22 17:04:50 -0800435 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436 unlock_kernel();
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200437
438 /*
439 * The boot idle thread must execute schedule()
Ingo Molnar1df21052007-07-09 18:51:58 +0200440 * at least once to get things moving:
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200441 */
Ingo Molnar1df21052007-07-09 18:51:58 +0200442 init_idle_bootup_task(current);
Nick Piggin5bfb5d62005-11-08 21:39:01 -0800443 preempt_enable_no_resched();
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200444 schedule();
Nick Piggin5bfb5d62005-11-08 21:39:01 -0800445 preempt_disable();
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200446
Nick Piggin5bfb5d62005-11-08 21:39:01 -0800447 /* Call into cpu_idle with preempt disabled */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448 cpu_idle();
Ingo Molnar1df21052007-07-09 18:51:58 +0200449}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450
451/* Check for early params. */
452static int __init do_early_param(char *param, char *val)
453{
454 struct obs_kernel_param *p;
455
456 for (p = __setup_start; p < __setup_end; p++) {
Yinghai Lu18a8bd92007-07-15 23:37:59 -0700457 if ((p->early && strcmp(param, p->str) == 0) ||
458 (strcmp(param, "console") == 0 &&
459 strcmp(p->str, "earlycon") == 0)
460 ) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461 if (p->setup_func(val) != 0)
462 printk(KERN_WARNING
463 "Malformed early option '%s'\n", param);
464 }
465 }
466 /* We accept everything at this stage. */
467 return 0;
468}
469
Magnus Damm13977092009-03-30 14:37:25 -0700470void __init parse_early_options(char *cmdline)
471{
472 parse_args("early options", cmdline, NULL, 0, do_early_param);
473}
474
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475/* Arch code calls this early on, or if not, just before other parsing. */
476void __init parse_early_param(void)
477{
478 static __initdata int done = 0;
479 static __initdata char tmp_cmdline[COMMAND_LINE_SIZE];
480
481 if (done)
482 return;
483
484 /* All fall through to do_early_param. */
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800485 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
Magnus Damm13977092009-03-30 14:37:25 -0700486 parse_early_options(tmp_cmdline);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487 done = 1;
488}
489
490/*
491 * Activate the first processor.
492 */
493
Stas Sergeev44fd2292006-03-23 02:59:44 -0800494static void __init boot_cpu_init(void)
495{
496 int cpu = smp_processor_id();
497 /* Mark the boot cpu "present", "online" etc for SMP and UP case */
Rusty Russell915441b2009-01-01 10:12:15 +1030498 set_cpu_online(cpu, true);
Peter Zijlstra933b0612009-12-16 18:04:31 +0100499 set_cpu_active(cpu, true);
Rusty Russell915441b2009-01-01 10:12:15 +1030500 set_cpu_present(cpu, true);
501 set_cpu_possible(cpu, true);
Stas Sergeev44fd2292006-03-23 02:59:44 -0800502}
503
Benjamin Herrenschmidt839ad622008-04-18 16:56:18 +1000504void __init __weak smp_setup_processor_id(void)
Andrew Morton033ab7f2006-06-30 01:55:50 -0700505{
506}
507
Benjamin Herrenschmidt8c9843e2008-04-18 16:56:15 +1000508void __init __weak thread_info_cache_init(void)
509{
510}
511
Pekka Enberg444f4782009-06-11 18:29:06 +0300512/*
513 * Set up kernel memory allocators
514 */
515static void __init mm_init(void)
516{
KAMEZAWA Hiroyukica371c02009-06-12 10:33:53 +0300517 /*
518 * page_cgroup requires countinous pages as memmap
519 * and it's bigger than MAX_ORDER unless SPARSEMEM.
520 */
521 page_cgroup_init_flatmem();
Pekka Enberg444f4782009-06-11 18:29:06 +0300522 mem_init();
523 kmem_cache_init();
Benjamin Herrenschmidtc868d552009-06-17 13:48:39 +1000524 pgtable_cache_init();
Pekka Enberg444f4782009-06-11 18:29:06 +0300525 vmalloc_init();
526}
527
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528asmlinkage void __init start_kernel(void)
529{
530 char * command_line;
531 extern struct kernel_param __start___param[], __stop___param[];
Andrew Morton033ab7f2006-06-30 01:55:50 -0700532
533 smp_setup_processor_id();
534
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700535 /*
536 * Need to run as early as possible, to initialize the
537 * lockdep hash:
538 */
539 lockdep_init();
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700540 debug_objects_early_init();
Ingo Molnar42059422008-02-14 09:44:08 +0100541
542 /*
543 * Set up the the initial canary ASAP:
544 */
545 boot_init_stack_canary();
546
Paul Menageddbcc7e2007-10-18 23:39:30 -0700547 cgroup_init_early();
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700548
549 local_irq_disable();
550 early_boot_irqs_off();
Ingo Molnar243c7622006-07-03 00:25:06 -0700551 early_init_irq_lock_class();
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700552
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553/*
554 * Interrupts are still disabled. Do necessary setups, then
555 * enable them
556 */
557 lock_kernel();
Thomas Gleixner906568c2007-02-16 01:28:01 -0800558 tick_init();
Stas Sergeev44fd2292006-03-23 02:59:44 -0800559 boot_cpu_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 page_address_init();
Alex Riesen657cafa2009-05-24 15:30:48 +0200561 printk(KERN_NOTICE "%s", linux_banner);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562 setup_arch(&command_line);
Balbir Singhcf475ad2008-04-29 01:00:16 -0700563 mm_init_owner(&init_mm, &init_task);
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800564 setup_command_line(command_line);
Mike Travise0982e92008-03-26 14:23:48 -0700565 setup_nr_cpu_ids();
Tejun Heod6647bd2009-07-21 17:11:50 +0900566 setup_per_cpu_areas();
Stas Sergeev44fd2292006-03-23 02:59:44 -0800567 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568
Pekka Enberg83b519e2009-06-10 19:40:04 +0300569 build_all_zonelists();
570 page_alloc_init();
571
572 printk(KERN_NOTICE "Kernel command line: %s\n", boot_command_line);
573 parse_early_param();
574 parse_args("Booting kernel", static_command_line, __start___param,
575 __stop___param - __start___param,
576 &unknown_bootoption);
577 /*
578 * These use large bootmem allocations and must precede
579 * kmem_cache_init()
580 */
581 pidhash_init();
Pekka Enberg83b519e2009-06-10 19:40:04 +0300582 vfs_caches_init_early();
583 sort_main_extable();
584 trap_init();
Pekka Enberg444f4782009-06-11 18:29:06 +0300585 mm_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586 /*
587 * Set up the scheduler prior starting any interrupts (such as the
588 * timer interrupt). Full topology setup happens at smp_init()
589 * time - but meanwhile we still have a functioning scheduler.
590 */
591 sched_init();
592 /*
593 * Disable preemption - early bootup scheduling is extremely
594 * fragile until we cpu_idle() for the first time.
595 */
596 preempt_disable();
Ard van Breemenc4a68302007-01-05 16:36:19 -0800597 if (!irqs_disabled()) {
598 printk(KERN_WARNING "start_kernel(): bug: interrupts were "
599 "enabled *very* early, fixing it\n");
600 local_irq_disable();
601 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602 rcu_init();
Yinghai Lu773e3eb2010-02-10 01:20:33 -0800603 radix_tree_init();
Yinghai Lu0b8f1ef2008-12-05 18:58:31 -0800604 /* init some links before init_ISA_irqs() */
605 early_irq_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 init_IRQ();
Catalin Marinas3c7b4e62009-06-11 13:22:39 +0100607 prio_tree_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608 init_timers();
Thomas Gleixnerc0a31322006-01-09 20:52:32 -0800609 hrtimers_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 softirq_init();
john stultzad596172006-06-26 00:25:06 -0700611 timekeeping_init();
john stultz88fecaa2006-07-03 00:24:04 -0700612 time_init();
Heiko Carstens93e02812006-07-03 00:24:24 -0700613 profile_init();
614 if (!irqs_disabled())
Ron Lee24d431d2008-11-27 02:31:57 +1030615 printk(KERN_CRIT "start_kernel(): bug: interrupts were "
616 "enabled early\n");
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700617 early_boot_irqs_on();
Heiko Carstens93e02812006-07-03 00:24:24 -0700618 local_irq_enable();
Benjamin Herrenschmidtdcce2842009-06-18 13:24:12 +1000619
620 /* Interrupts are enabled now so all GFP allocations are safe. */
Rafael J. Wysocki452aa692010-03-05 13:42:13 -0800621 gfp_allowed_mask = __GFP_BITS_MASK;
Benjamin Herrenschmidtdcce2842009-06-18 13:24:12 +1000622
Pekka Enberg7e85ee02009-06-12 14:03:06 +0300623 kmem_cache_init_late();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624
625 /*
626 * HACK ALERT! This is early. We're enabling the console before
627 * we've done PCI setups etc, and console_init() must be aware of
628 * this. But we do want output early, in case something goes wrong.
629 */
630 console_init();
631 if (panic_later)
632 panic(panic_later, panic_param);
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700633
634 lockdep_info();
635
Ingo Molnar9a11b49a2006-07-03 00:24:33 -0700636 /*
637 * Need to run this when irqs are enabled, because it wants
638 * to self-test [hard/soft]-irqs on/off lock inversion bugs
639 * too:
640 */
641 locking_selftest();
642
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643#ifdef CONFIG_BLK_DEV_INITRD
644 if (initrd_start && !initrd_below_start_ok &&
Geert Uytterhoevenbd673c72008-07-29 22:33:36 -0700645 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646 printk(KERN_CRIT "initrd overwritten (0x%08lx < 0x%08lx) - "
Geert Uytterhoevenfb6624e2008-07-17 21:16:36 +0200647 "disabling it.\n",
Geert Uytterhoevenbd673c72008-07-29 22:33:36 -0700648 page_to_pfn(virt_to_page((void *)initrd_start)),
649 min_low_pfn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650 initrd_start = 0;
651 }
652#endif
KAMEZAWA Hiroyuki94b6da52008-10-22 14:15:05 -0700653 page_cgroup_init();
Thomas Gleixnera03c2a42008-02-09 23:24:09 +0100654 enable_debug_pagealloc();
Eduard - Gabriel Munteanub9ce08c2008-08-10 20:14:03 +0300655 kmemtrace_init();
Catalin Marinas3c7b4e62009-06-11 13:22:39 +0100656 kmemleak_init();
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700657 debug_objects_mem_init();
Akinobu Mita199f0ca2008-04-29 01:03:13 -0700658 idr_init_cache();
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700659 setup_per_cpu_pageset();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660 numa_policy_init();
661 if (late_time_init)
662 late_time_init();
Thomas Gleixnerfa84e9e2009-08-21 22:01:12 +0200663 sched_clock_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664 calibrate_delay();
665 pidmap_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666 anon_vma_init();
667#ifdef CONFIG_X86
668 if (efi_enabled)
669 efi_enter_virtual_mode();
670#endif
Benjamin Herrenschmidt8c9843e2008-04-18 16:56:15 +1000671 thread_info_cache_init();
David Howellsd84f4f92008-11-14 10:39:23 +1100672 cred_init();
Jan Beulich44813742009-09-21 17:03:05 -0700673 fork_init(totalram_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674 proc_caches_init();
675 buffer_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676 key_init();
677 security_init();
Jan Beulich44813742009-09-21 17:03:05 -0700678 vfs_caches_init(totalram_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679 signals_init();
680 /* rootfs populating might need page-writeback */
681 page_writeback_init();
682#ifdef CONFIG_PROC_FS
683 proc_root_init();
684#endif
Paul Menageddbcc7e2007-10-18 23:39:30 -0700685 cgroup_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 cpuset_init();
Shailabh Nagarc7572492006-07-14 00:24:40 -0700687 taskstats_init_early();
Shailabh Nagarca74e922006-07-14 00:24:36 -0700688 delayacct_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689
690 check_bugs();
691
692 acpi_early_init(); /* before LAPIC and SMP init */
Feng Tang6ae69962009-08-14 15:13:46 -0400693 sfi_init_late();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700694
Steven Rostedt68bf21a2008-08-14 15:45:08 -0400695 ftrace_init();
696
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697 /* Do the rest non-__init'ed, we're now alive */
698 rest_init();
699}
700
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -0700701/* Call all constructor functions linked into the kernel. */
702static void __init do_ctors(void)
703{
704#ifdef CONFIG_CONSTRUCTORS
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800705 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start;
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -0700706
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800707 for (; fn < (ctor_fn_t *) __ctors_end; fn++)
708 (*fn)();
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -0700709#endif
710}
711
Arjan van de Ven22a9d642009-01-07 08:45:46 -0800712int initcall_debug;
Rusty Russelld0ea3d72008-10-22 10:00:23 -0500713core_param(initcall_debug, initcall_debug, bool, 0644);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714
Ingo Molnar4a683bf2009-08-21 12:53:36 +0200715static char msgbuf[64];
716static struct boot_trace_call call;
717static struct boot_trace_ret ret;
718
Arjan van de Ven59f94152008-07-30 12:49:02 -0700719int do_one_initcall(initcall_t fn)
Linus Torvaldse0df1542008-05-15 18:14:01 -0700720{
721 int count = preempt_count();
Frederic Weisbecker74239072008-11-11 23:24:42 +0100722 ktime_t calltime, delta, rettime;
Linus Torvaldse0df1542008-05-15 18:14:01 -0700723
724 if (initcall_debug) {
Frederic Weisbecker74239072008-11-11 23:24:42 +0100725 call.caller = task_pid_nr(current);
726 printk("calling %pF @ %i\n", fn, call.caller);
727 calltime = ktime_get();
728 trace_boot_call(&call, fn);
Frederic Weisbecker71566a02008-10-31 12:57:20 +0100729 enable_boot_trace();
Linus Torvaldse0df1542008-05-15 18:14:01 -0700730 }
731
Frederic Weisbecker74239072008-11-11 23:24:42 +0100732 ret.result = fn();
Linus Torvaldse0df1542008-05-15 18:14:01 -0700733
734 if (initcall_debug) {
Frederic Weisbecker71566a02008-10-31 12:57:20 +0100735 disable_boot_trace();
Frederic Weisbecker74239072008-11-11 23:24:42 +0100736 rettime = ktime_get();
737 delta = ktime_sub(rettime, calltime);
Will Newton1d926f22008-11-21 14:08:59 -0800738 ret.duration = (unsigned long long) ktime_to_ns(delta) >> 10;
Frederic Weisbecker74239072008-11-11 23:24:42 +0100739 trace_boot_ret(&ret, fn);
Tim Birdca538f62008-10-09 15:23:05 -0700740 printk("initcall %pF returned %d after %Ld usecs\n", fn,
Frederic Weisbecker74239072008-11-11 23:24:42 +0100741 ret.result, ret.duration);
Linus Torvaldse0df1542008-05-15 18:14:01 -0700742 }
743
744 msgbuf[0] = 0;
745
Frederic Weisbecker74239072008-11-11 23:24:42 +0100746 if (ret.result && ret.result != -ENODEV && initcall_debug)
747 sprintf(msgbuf, "error code %d ", ret.result);
Linus Torvaldse0df1542008-05-15 18:14:01 -0700748
749 if (preempt_count() != count) {
Cyrill Gorcunova76bfd02008-05-15 13:52:41 -0700750 strlcat(msgbuf, "preemption imbalance ", sizeof(msgbuf));
Linus Torvaldse0df1542008-05-15 18:14:01 -0700751 preempt_count() = count;
752 }
753 if (irqs_disabled()) {
Cyrill Gorcunova76bfd02008-05-15 13:52:41 -0700754 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf));
Linus Torvaldse0df1542008-05-15 18:14:01 -0700755 local_irq_enable();
756 }
757 if (msgbuf[0]) {
Linus Torvalds96d746c2008-10-03 13:38:07 -0700758 printk("initcall %pF returned with %s\n", fn, msgbuf);
Linus Torvaldse0df1542008-05-15 18:14:01 -0700759 }
Arjan van de Ven59f94152008-07-30 12:49:02 -0700760
Frederic Weisbecker74239072008-11-11 23:24:42 +0100761 return ret.result;
Linus Torvaldse0df1542008-05-15 18:14:01 -0700762}
763
764
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700765extern initcall_t __initcall_start[], __initcall_end[], __early_initcall_end[];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766
767static void __init do_initcalls(void)
768{
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800769 initcall_t *fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700770
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800771 for (fn = __early_initcall_end; fn < __initcall_end; fn++)
772 do_one_initcall(*fn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700773
774 /* Make sure there is no pending stuff from the initcall sequence */
775 flush_scheduled_work();
776}
777
778/*
779 * Ok, the machine is now initialized. None of the devices
780 * have been touched yet, but the CPU subsystem is up and
781 * running, and memory and process management works.
782 *
783 * Now we can finally start doing some real work..
784 */
785static void __init do_basic_setup(void)
786{
Linus Torvalds4403b402008-10-25 19:53:38 -0700787 init_workqueues();
Lai Jiangshan759ee092009-03-25 17:06:30 +0800788 cpuset_init_smp();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789 usermodehelper_init();
Kay Sievers2b2af542009-04-30 15:23:42 +0200790 init_tmpfs();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700791 driver_init();
Eric W. Biedermanb04c3af2007-02-14 00:33:57 -0800792 init_irq_proc();
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -0700793 do_ctors();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794 do_initcalls();
795}
796
Eduard - Gabriel Munteanu7babe8d2008-07-25 19:45:11 -0700797static void __init do_pre_smp_initcalls(void)
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700798{
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800799 initcall_t *fn;
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700800
H Hartley Sweeten196a15b2009-12-14 18:00:18 -0800801 for (fn = __initcall_start; fn < __early_initcall_end; fn++)
802 do_one_initcall(*fn);
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700803}
804
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805static void run_init_process(char *init_filename)
806{
807 argv_init[0] = init_filename;
Arnd Bergmann67608562006-10-02 02:18:26 -0700808 kernel_execve(init_filename, argv_init, envp_init);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809}
810
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100811/* This is a non __init function. Force it to be noinline otherwise gcc
812 * makes it inline to init() and it becomes part of init.text section
813 */
Rakib Mullickf99ebf02009-01-06 14:40:38 -0800814static noinline int init_post(void)
Hannes Ederacdd0522009-03-31 15:23:50 -0700815 __releases(kernel_lock)
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100816{
Arjan van de Ven22a9d642009-01-07 08:45:46 -0800817 /* need to finish all async __init code before freeing the memory */
818 async_synchronize_full();
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100819 free_initmem();
820 unlock_kernel();
821 mark_rodata_ro();
822 system_state = SYSTEM_RUNNING;
823 numa_default_policy();
824
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100825
Oleg Nesterovfae5fa42008-04-30 00:53:03 -0700826 current->signal->flags |= SIGNAL_UNKILLABLE;
827
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100828 if (ramdisk_execute_command) {
829 run_init_process(ramdisk_execute_command);
830 printk(KERN_WARNING "Failed to execute %s\n",
831 ramdisk_execute_command);
832 }
833
834 /*
835 * We try each of these until one succeeds.
836 *
837 * The Bourne shell can be used instead of init if we are
838 * trying to recover a really broken machine.
839 */
840 if (execute_command) {
841 run_init_process(execute_command);
842 printk(KERN_WARNING "Failed to execute %s. Attempting "
843 "defaults...\n", execute_command);
844 }
845 run_init_process("/sbin/init");
846 run_init_process("/etc/init");
847 run_init_process("/bin/init");
848 run_init_process("/bin/sh");
849
Andreas Mohr9a85b8d2010-03-05 13:42:39 -0800850 panic("No init found. Try passing init= option to kernel. "
851 "See Linux Documentation/init.txt for guidance.");
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100852}
853
Sam Ravnborgaae5f662007-02-26 16:45:41 +0100854static int __init kernel_init(void * unused)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700855{
856 lock_kernel();
Miao Xie58568d22009-06-16 15:31:49 -0700857
858 /*
859 * init can allocate pages on any node
860 */
861 set_mems_allowed(node_possible_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862 /*
863 * init can run on any cpu.
864 */
Rusty Russell1a2142a2009-03-30 22:05:10 -0600865 set_cpus_allowed_ptr(current, cpu_all_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700866 /*
867 * Tell the world that we're going to be the grim
868 * reaper of innocent orphaned children.
869 *
870 * We don't want people to have to make incorrect
871 * assumptions about where in the task array this
872 * can be found.
873 */
Sukadev Bhattiprolu84d73782006-12-08 02:38:01 -0800874 init_pid_ns.child_reaper = current;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700875
Cedric Le Goater9ec52092006-10-02 02:19:00 -0700876 cad_pid = task_pid(current);
877
Andi Kleenca74a6f2008-01-30 13:33:17 +0100878 smp_prepare_cpus(setup_max_cpus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879
880 do_pre_smp_initcalls();
Frédéric Weisbecker3bf77af2008-09-23 11:38:18 +0100881 start_boot_trace();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883 smp_init();
884 sched_init_smp();
885
Linus Torvalds1da177e2005-04-16 15:20:36 -0700886 do_basic_setup();
887
Eric W. Biederman2bd3a9972010-03-02 23:53:19 -0800888 /* Open the /dev/console on the rootfs, this should never fail */
889 if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
890 printk(KERN_WARNING "Warning: unable to open an initial console.\n");
891
892 (void) sys_dup(0);
893 (void) sys_dup(0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894 /*
895 * check if there is an early userspace init. If yes, let it do all
896 * the work
897 */
Olof Johanssonffdfc402005-09-06 15:17:19 -0700898
899 if (!ramdisk_execute_command)
900 ramdisk_execute_command = "/init";
901
902 if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
903 ramdisk_execute_command = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700904 prepare_namespace();
Olof Johanssonffdfc402005-09-06 15:17:19 -0700905 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906
907 /*
908 * Ok, we have completed the initial bootup, and
909 * we're essentially up and running. Get rid of the
910 * initmem segments and start the user-mode stuff..
911 */
Frederic Weisbecker71566a02008-10-31 12:57:20 +0100912
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100913 init_post();
914 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915}