blob: 80b04b6c5157c85151669fdfe2864c16f876680e [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>
17#include <linux/string.h>
18#include <linux/ctype.h>
19#include <linux/delay.h>
20#include <linux/utsname.h>
21#include <linux/ioport.h>
22#include <linux/init.h>
23#include <linux/smp_lock.h>
24#include <linux/initrd.h>
25#include <linux/hdreg.h>
26#include <linux/bootmem.h>
27#include <linux/tty.h>
28#include <linux/gfp.h>
29#include <linux/percpu.h>
30#include <linux/kmod.h>
31#include <linux/kernel_stat.h>
Rusty Russelld7cd5612006-12-07 02:14:08 +010032#include <linux/start_kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <linux/security.h>
34#include <linux/workqueue.h>
35#include <linux/profile.h>
36#include <linux/rcupdate.h>
37#include <linux/moduleparam.h>
38#include <linux/kallsyms.h>
39#include <linux/writeback.h>
40#include <linux/cpu.h>
41#include <linux/cpuset.h>
Paul Menageddbcc7e2007-10-18 23:39:30 -070042#include <linux/cgroup.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070043#include <linux/efi.h>
Thomas Gleixner906568c2007-02-16 01:28:01 -080044#include <linux/tick.h>
Andrew Morton6168a702007-02-17 21:22:39 -080045#include <linux/interrupt.h>
Shailabh Nagarc7572492006-07-14 00:24:40 -070046#include <linux/taskstats_kern.h>
Shailabh Nagarca74e922006-07-14 00:24:36 -070047#include <linux/delayacct.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070048#include <linux/unistd.h>
49#include <linux/rmap.h>
50#include <linux/mempolicy.h>
51#include <linux/key.h>
Jan Beulich4552d5d2006-06-26 13:57:28 +020052#include <linux/unwind.h>
Adrian Bunkb6cd0b72006-06-27 02:53:54 -070053#include <linux/buffer_head.h>
Ingo Molnar9a11b49a2006-07-03 00:24:33 -070054#include <linux/debug_locks.h>
Ingo Molnarfbb9ce92006-07-03 00:24:50 -070055#include <linux/lockdep.h>
Sukadev Bhattiprolu84d73782006-12-08 02:38:01 -080056#include <linux/pid_namespace.h>
Adrian Bunk1f217822006-12-19 13:01:28 -080057#include <linux/device.h>
Eric W. Biederman73c27992007-05-09 02:34:32 -070058#include <linux/kthread.h>
Adrian Bunke6fe6642007-11-09 22:39:39 +010059#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070060
61#include <asm/io.h>
62#include <asm/bugs.h>
63#include <asm/setup.h>
Andi Kleena9401992005-07-28 21:15:30 -070064#include <asm/sections.h>
Arjan van de Ven37b73c82006-01-06 00:12:01 -080065#include <asm/cacheflush.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070066
Linus Torvalds1da177e2005-04-16 15:20:36 -070067#ifdef CONFIG_X86_LOCAL_APIC
68#include <asm/smp.h>
69#endif
70
71/*
Coywolf Qi Hunt69c99ac2006-01-14 13:21:11 -080072 * This is one of the first .c files built. Error out early if we have compiler
73 * trouble.
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070075
Andrew Mortonf1a60db2006-12-06 20:39:59 -080076#if __GNUC__ == 4 && __GNUC_MINOR__ == 1 && __GNUC_PATCHLEVEL__ == 0
77#warning gcc-4.1.0 is known to miscompile the kernel. A different compiler version is recommended.
78#endif
79
Sam Ravnborgaae5f662007-02-26 16:45:41 +010080static int kernel_init(void *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070081
82extern void init_IRQ(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070083extern void fork_init(unsigned long);
84extern void mca_init(void);
85extern void sbus_init(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070086extern void signals_init(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070087extern void pidhash_init(void);
88extern void pidmap_init(void);
89extern void prio_tree_init(void);
90extern void radix_tree_init(void);
91extern void free_initmem(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070092#ifdef CONFIG_ACPI
93extern void acpi_early_init(void);
94#else
95static inline void acpi_early_init(void) { }
96#endif
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
101#ifdef CONFIG_TC
102extern void tc_init(void);
103#endif
104
105enum system_states system_state;
106EXPORT_SYMBOL(system_state);
107
108/*
109 * Boot command-line arguments
110 */
111#define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
112#define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
113
114extern void time_init(void);
115/* Default late time init is NULL. archs can override this later. */
116void (*late_time_init)(void);
117extern void softirq_init(void);
118
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800119/* Untouched command line saved by arch-specific code. */
120char __initdata boot_command_line[COMMAND_LINE_SIZE];
121/* Untouched saved command line (eg. for /proc) */
122char *saved_command_line;
123/* Command line for parameter parsing */
124static char *static_command_line;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125
126static char *execute_command;
Olof Johanssonffdfc402005-09-06 15:17:19 -0700127static char *ramdisk_execute_command;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128
Jan Beulich8b3b2952007-07-15 23:41:07 -0700129#ifdef CONFIG_SMP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130/* Setup configured maximum number of CPUs to activate */
Jan Beulich8b3b2952007-07-15 23:41:07 -0700131static unsigned int __initdata max_cpus = NR_CPUS;
Vivek Goyal7e962872006-09-27 01:50:44 -0700132
133/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 * Setup routine for controlling SMP activation
135 *
136 * Command-line option of "nosmp" or "maxcpus=0" will disable SMP
137 * activation entirely (the MPS table probe still happens, though).
138 *
139 * Command-line option of "maxcpus=<NUM>", where <NUM> is an integer
140 * greater than 0, limits the maximum number of CPUs activated in
141 * SMP mode to <NUM>.
142 */
Len Brown61ec7562007-08-16 03:34:22 -0400143#ifndef CONFIG_X86_IO_APIC
144static inline void disable_ioapic_setup(void) {};
145#endif
146
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147static int __init nosmp(char *str)
148{
149 max_cpus = 0;
Len Brown61ec7562007-08-16 03:34:22 -0400150 disable_ioapic_setup();
Jan Beulich8b3b2952007-07-15 23:41:07 -0700151 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152}
153
Jan Beulich8b3b2952007-07-15 23:41:07 -0700154early_param("nosmp", nosmp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155
156static int __init maxcpus(char *str)
157{
158 get_option(&str, &max_cpus);
Len Brown61ec7562007-08-16 03:34:22 -0400159 if (max_cpus == 0)
160 disable_ioapic_setup();
161
162 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163}
164
Hugh Dickins81340972007-08-27 16:02:12 +0100165early_param("maxcpus", maxcpus);
Jan Beulich8b3b2952007-07-15 23:41:07 -0700166#else
167#define max_cpus NR_CPUS
168#endif
169
170/*
171 * If set, this is an indication to the drivers that reset the underlying
172 * device before going ahead with the initialization otherwise driver might
173 * rely on the BIOS and skip the reset operation.
174 *
175 * This is useful if kernel is booting in an unreliable environment.
176 * For ex. kdump situaiton where previous kernel has crashed, BIOS has been
177 * skipped and devices will be in unknown state.
178 */
179unsigned int reset_devices;
180EXPORT_SYMBOL(reset_devices);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181
Vivek Goyal7e962872006-09-27 01:50:44 -0700182static int __init set_reset_devices(char *str)
183{
184 reset_devices = 1;
185 return 1;
186}
187
188__setup("reset_devices", set_reset_devices);
189
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190static char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
191char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
192static const char *panic_later, *panic_param;
193
194extern struct obs_kernel_param __setup_start[], __setup_end[];
195
196static int __init obsolete_checksetup(char *line)
197{
198 struct obs_kernel_param *p;
Rusty Russell33df0d12006-09-26 10:52:32 +0200199 int had_early_param = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200
201 p = __setup_start;
202 do {
203 int n = strlen(p->str);
204 if (!strncmp(line, p->str, n)) {
205 if (p->early) {
Rusty Russell33df0d12006-09-26 10:52:32 +0200206 /* Already done in parse_early_param?
207 * (Needs exact match on param part).
208 * Keep iterating, as we can have early
209 * params and __setups of same names 8( */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210 if (line[n] == '\0' || line[n] == '=')
Rusty Russell33df0d12006-09-26 10:52:32 +0200211 had_early_param = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212 } else if (!p->setup_func) {
213 printk(KERN_WARNING "Parameter %s is obsolete,"
214 " ignored\n", p->str);
215 return 1;
216 } else if (p->setup_func(line + n))
217 return 1;
218 }
219 p++;
220 } while (p < __setup_end);
Rusty Russell33df0d12006-09-26 10:52:32 +0200221
222 return had_early_param;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223}
224
225/*
226 * This should be approx 2 Bo*oMips to start (note initial shift), and will
227 * still work even if initially too large, it will just take slightly longer
228 */
229unsigned long loops_per_jiffy = (1<<12);
230
231EXPORT_SYMBOL(loops_per_jiffy);
232
233static int __init debug_kernel(char *str)
234{
235 if (*str)
236 return 0;
237 console_loglevel = 10;
238 return 1;
239}
240
241static int __init quiet_kernel(char *str)
242{
243 if (*str)
244 return 0;
245 console_loglevel = 4;
246 return 1;
247}
248
249__setup("debug", debug_kernel);
250__setup("quiet", quiet_kernel);
251
252static int __init loglevel(char *str)
253{
254 get_option(&str, &console_loglevel);
255 return 1;
256}
257
258__setup("loglevel=", loglevel);
259
260/*
261 * Unknown boot options get handed to init, unless they look like
262 * failed parameters
263 */
264static int __init unknown_bootoption(char *param, char *val)
265{
266 /* Change NUL term back to "=", to make "param" the whole string. */
267 if (val) {
268 /* param=val or param="val"? */
269 if (val == param+strlen(param)+1)
270 val[-1] = '=';
271 else if (val == param+strlen(param)+2) {
272 val[-2] = '=';
273 memmove(val-1, val, strlen(val)+1);
274 val--;
275 } else
276 BUG();
277 }
278
279 /* Handle obsolete-style parameters */
280 if (obsolete_checksetup(param))
281 return 0;
282
283 /*
Simon Arlott211fee82007-10-20 01:28:29 +0200284 * Preemptive maintenance for "why didn't my misspelled command
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285 * line work?"
286 */
287 if (strchr(param, '.') && (!val || strchr(param, '.') < val)) {
288 printk(KERN_ERR "Unknown boot option `%s': ignoring\n", param);
289 return 0;
290 }
291
292 if (panic_later)
293 return 0;
294
295 if (val) {
296 /* Environment option */
297 unsigned int i;
298 for (i = 0; envp_init[i]; i++) {
299 if (i == MAX_INIT_ENVS) {
300 panic_later = "Too many boot env vars at `%s'";
301 panic_param = param;
302 }
303 if (!strncmp(param, envp_init[i], val - param))
304 break;
305 }
306 envp_init[i] = param;
307 } else {
308 /* Command line option */
309 unsigned int i;
310 for (i = 0; argv_init[i]; i++) {
311 if (i == MAX_INIT_ARGS) {
312 panic_later = "Too many boot init vars at `%s'";
313 panic_param = param;
314 }
315 }
316 argv_init[i] = param;
317 }
318 return 0;
319}
320
321static int __init init_setup(char *str)
322{
323 unsigned int i;
324
325 execute_command = str;
326 /*
327 * In case LILO is going to boot us with default command line,
328 * it prepends "auto" before the whole cmdline which makes
329 * the shell think it should execute a script with such name.
330 * So we ignore all arguments entered _before_ init=... [MJ]
331 */
332 for (i = 1; i < MAX_INIT_ARGS; i++)
333 argv_init[i] = NULL;
334 return 1;
335}
336__setup("init=", init_setup);
337
Olof Johanssonffdfc402005-09-06 15:17:19 -0700338static int __init rdinit_setup(char *str)
339{
340 unsigned int i;
341
342 ramdisk_execute_command = str;
343 /* See "auto" comment in init_setup */
344 for (i = 1; i < MAX_INIT_ARGS; i++)
345 argv_init[i] = NULL;
346 return 1;
347}
348__setup("rdinit=", rdinit_setup);
349
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350#ifndef CONFIG_SMP
351
352#ifdef CONFIG_X86_LOCAL_APIC
353static void __init smp_init(void)
354{
355 APIC_init_uniprocessor();
356}
357#else
358#define smp_init() do { } while (0)
359#endif
360
361static inline void setup_per_cpu_areas(void) { }
362static inline void smp_prepare_cpus(unsigned int maxcpus) { }
363
364#else
365
366#ifdef __GENERIC_PER_CPU
Eric Dumazetb73b4592006-03-23 03:01:07 -0800367unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368
369EXPORT_SYMBOL(__per_cpu_offset);
370
371static void __init setup_per_cpu_areas(void)
372{
373 unsigned long size, i;
374 char *ptr;
Eric Dumazet63872f82006-03-23 03:01:04 -0800375 unsigned long nr_possible_cpus = num_possible_cpus();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376
377 /* Copy section for each CPU (we discard the original) */
Jeremy Fitzhardingeb6e35902007-05-02 19:27:12 +0200378 size = ALIGN(PERCPU_ENOUGH_ROOM, PAGE_SIZE);
379 ptr = alloc_bootmem_pages(size * nr_possible_cpus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380
KAMEZAWA Hiroyuki0a945022006-03-28 01:56:37 -0800381 for_each_possible_cpu(i) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382 __per_cpu_offset[i] = ptr - __per_cpu_start;
383 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
Eric Dumazet63872f82006-03-23 03:01:04 -0800384 ptr += size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385 }
386}
387#endif /* !__GENERIC_PER_CPU */
388
389/* Called by boot processor to activate the rest. */
390static void __init smp_init(void)
391{
Christoph Lameter53b8a312007-02-20 13:57:51 -0800392 unsigned int cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393
394 /* FIXME: This should be done in userspace --RR */
Christoph Lameter53b8a312007-02-20 13:57:51 -0800395 for_each_present_cpu(cpu) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396 if (num_online_cpus() >= max_cpus)
397 break;
Christoph Lameter53b8a312007-02-20 13:57:51 -0800398 if (!cpu_online(cpu))
399 cpu_up(cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 }
401
402 /* Any cleanup work */
403 printk(KERN_INFO "Brought up %ld CPUs\n", (long)num_online_cpus());
404 smp_cpus_done(max_cpus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405}
406
407#endif
408
409/*
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800410 * We need to store the untouched command line for future reference.
411 * We also need to store the touched command line since the parameter
412 * parsing is performed in place, and we should allow a component to
413 * store reference of name/value for future reference.
414 */
415static void __init setup_command_line(char *command_line)
416{
417 saved_command_line = alloc_bootmem(strlen (boot_command_line)+1);
418 static_command_line = alloc_bootmem(strlen (command_line)+1);
419 strcpy (saved_command_line, boot_command_line);
420 strcpy (static_command_line, command_line);
421}
422
423/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424 * We need to finalize in a non-__init function or else race conditions
425 * between the root thread and the init thread may cause start_kernel to
426 * be reaped by free_initmem before the root thread has proceeded to
427 * cpu_idle.
428 *
429 * gcc-3.4 accidentally inlines this function, so use noinline.
430 */
431
Sam Ravnborg92080302007-05-17 20:43:54 +0200432static void noinline __init_refok rest_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 __releases(kernel_lock)
434{
Eric W. Biederman73c27992007-05-09 02:34:32 -0700435 int pid;
436
Sam Ravnborgaae5f662007-02-26 16:45:41 +0100437 kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438 numa_default_policy();
Eric W. Biederman73c27992007-05-09 02:34:32 -0700439 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
440 kthreadd_task = find_task_by_pid(pid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441 unlock_kernel();
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200442
443 /*
444 * The boot idle thread must execute schedule()
Ingo Molnar1df21052007-07-09 18:51:58 +0200445 * at least once to get things moving:
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200446 */
Ingo Molnar1df21052007-07-09 18:51:58 +0200447 init_idle_bootup_task(current);
Nick Piggin5bfb5d62005-11-08 21:39:01 -0800448 preempt_enable_no_resched();
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200449 schedule();
Nick Piggin5bfb5d62005-11-08 21:39:01 -0800450 preempt_disable();
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200451
Nick Piggin5bfb5d62005-11-08 21:39:01 -0800452 /* Call into cpu_idle with preempt disabled */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453 cpu_idle();
Ingo Molnar1df21052007-07-09 18:51:58 +0200454}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455
456/* Check for early params. */
457static int __init do_early_param(char *param, char *val)
458{
459 struct obs_kernel_param *p;
460
461 for (p = __setup_start; p < __setup_end; p++) {
Yinghai Lu18a8bd92007-07-15 23:37:59 -0700462 if ((p->early && strcmp(param, p->str) == 0) ||
463 (strcmp(param, "console") == 0 &&
464 strcmp(p->str, "earlycon") == 0)
465 ) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 if (p->setup_func(val) != 0)
467 printk(KERN_WARNING
468 "Malformed early option '%s'\n", param);
469 }
470 }
471 /* We accept everything at this stage. */
472 return 0;
473}
474
475/* 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);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486 parse_args("early options", tmp_cmdline, NULL, 0, do_early_param);
487 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 */
498 cpu_set(cpu, cpu_online_map);
499 cpu_set(cpu, cpu_present_map);
500 cpu_set(cpu, cpu_possible_map);
501}
502
Andrew Morton033ab7f2006-06-30 01:55:50 -0700503void __init __attribute__((weak)) smp_setup_processor_id(void)
504{
505}
506
Linus Torvalds1da177e2005-04-16 15:20:36 -0700507asmlinkage void __init start_kernel(void)
508{
509 char * command_line;
510 extern struct kernel_param __start___param[], __stop___param[];
Andrew Morton033ab7f2006-06-30 01:55:50 -0700511
512 smp_setup_processor_id();
513
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700514 /*
515 * Need to run as early as possible, to initialize the
516 * lockdep hash:
517 */
Andi Kleenc9538ed2006-09-26 10:52:34 +0200518 unwind_init();
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700519 lockdep_init();
Paul Menageddbcc7e2007-10-18 23:39:30 -0700520 cgroup_init_early();
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700521
522 local_irq_disable();
523 early_boot_irqs_off();
Ingo Molnar243c7622006-07-03 00:25:06 -0700524 early_init_irq_lock_class();
Ingo Molnarfbb9ce92006-07-03 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 */
530 lock_kernel();
Thomas Gleixner906568c2007-02-16 01:28:01 -0800531 tick_init();
Stas Sergeev44fd2292006-03-23 02:59:44 -0800532 boot_cpu_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533 page_address_init();
534 printk(KERN_NOTICE);
Linus Torvalds89937802006-12-11 09:28:46 -0800535 printk(linux_banner);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 setup_arch(&command_line);
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800537 setup_command_line(command_line);
Jan Beulich690a9732006-10-21 18:37:01 +0200538 unwind_setup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539 setup_per_cpu_areas();
Stas Sergeev44fd2292006-03-23 02:59:44 -0800540 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541
542 /*
543 * Set up the scheduler prior starting any interrupts (such as the
544 * timer interrupt). Full topology setup happens at smp_init()
545 * time - but meanwhile we still have a functioning scheduler.
546 */
547 sched_init();
548 /*
549 * Disable preemption - early bootup scheduling is extremely
550 * fragile until we cpu_idle() for the first time.
551 */
552 preempt_disable();
553 build_all_zonelists();
554 page_alloc_init();
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800555 printk(KERN_NOTICE "Kernel command line: %s\n", boot_command_line);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 parse_early_param();
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800557 parse_args("Booting kernel", static_command_line, __start___param,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558 __stop___param - __start___param,
559 &unknown_bootoption);
Ard van Breemenc4a68302007-01-05 16:36:19 -0800560 if (!irqs_disabled()) {
561 printk(KERN_WARNING "start_kernel(): bug: interrupts were "
562 "enabled *very* early, fixing it\n");
563 local_irq_disable();
564 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 sort_main_extable();
566 trap_init();
567 rcu_init();
568 init_IRQ();
569 pidhash_init();
570 init_timers();
Thomas Gleixnerc0a31322006-01-09 20:52:32 -0800571 hrtimers_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 softirq_init();
john stultzad596172006-06-26 00:25:06 -0700573 timekeeping_init();
john stultz88fecaa2006-07-03 00:24:04 -0700574 time_init();
Heiko Carstens93e02812006-07-03 00:24:24 -0700575 profile_init();
576 if (!irqs_disabled())
577 printk("start_kernel(): bug: interrupts were enabled early\n");
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700578 early_boot_irqs_on();
Heiko Carstens93e02812006-07-03 00:24:24 -0700579 local_irq_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580
581 /*
582 * HACK ALERT! This is early. We're enabling the console before
583 * we've done PCI setups etc, and console_init() must be aware of
584 * this. But we do want output early, in case something goes wrong.
585 */
586 console_init();
587 if (panic_later)
588 panic(panic_later, panic_param);
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700589
590 lockdep_info();
591
Ingo Molnar9a11b49a2006-07-03 00:24:33 -0700592 /*
593 * Need to run this when irqs are enabled, because it wants
594 * to self-test [hard/soft]-irqs on/off lock inversion bugs
595 * too:
596 */
597 locking_selftest();
598
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599#ifdef CONFIG_BLK_DEV_INITRD
600 if (initrd_start && !initrd_below_start_ok &&
601 initrd_start < min_low_pfn << PAGE_SHIFT) {
602 printk(KERN_CRIT "initrd overwritten (0x%08lx < 0x%08lx) - "
603 "disabling it.\n",initrd_start,min_low_pfn << PAGE_SHIFT);
604 initrd_start = 0;
605 }
606#endif
607 vfs_caches_init_early();
Paul Jacksonc417f022006-01-08 01:02:01 -0800608 cpuset_init_early();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609 mem_init();
610 kmem_cache_init();
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700611 setup_per_cpu_pageset();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 numa_policy_init();
613 if (late_time_init)
614 late_time_init();
615 calibrate_delay();
616 pidmap_init();
617 pgtable_cache_init();
618 prio_tree_init();
619 anon_vma_init();
620#ifdef CONFIG_X86
621 if (efi_enabled)
622 efi_enter_virtual_mode();
623#endif
624 fork_init(num_physpages);
625 proc_caches_init();
626 buffer_init();
627 unnamed_dev_init();
628 key_init();
629 security_init();
630 vfs_caches_init(num_physpages);
631 radix_tree_init();
632 signals_init();
633 /* rootfs populating might need page-writeback */
634 page_writeback_init();
635#ifdef CONFIG_PROC_FS
636 proc_root_init();
637#endif
Paul Menageddbcc7e2007-10-18 23:39:30 -0700638 cgroup_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639 cpuset_init();
Shailabh Nagarc7572492006-07-14 00:24:40 -0700640 taskstats_init_early();
Shailabh Nagarca74e922006-07-14 00:24:36 -0700641 delayacct_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642
643 check_bugs();
644
645 acpi_early_init(); /* before LAPIC and SMP init */
646
647 /* Do the rest non-__init'ed, we're now alive */
648 rest_init();
649}
650
651static int __initdata initcall_debug;
652
653static int __init initcall_debug_setup(char *str)
654{
655 initcall_debug = 1;
656 return 1;
657}
658__setup("initcall_debug", initcall_debug_setup);
659
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660extern initcall_t __initcall_start[], __initcall_end[];
661
662static void __init do_initcalls(void)
663{
664 initcall_t *call;
665 int count = preempt_count();
666
667 for (call = __initcall_start; call < __initcall_end; call++) {
Ingo Molnar8f0c45c2007-05-08 00:28:26 -0700668 ktime_t t0, t1, delta;
Andrew Mortonc1cda482006-03-25 03:07:15 -0800669 char *msg = NULL;
670 char msgbuf[40];
671 int result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672
673 if (initcall_debug) {
Andrew Mortonc1cda482006-03-25 03:07:15 -0800674 printk("Calling initcall 0x%p", *call);
675 print_fn_descriptor_symbol(": %s()",
676 (unsigned long) *call);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677 printk("\n");
Ingo Molnar8f0c45c2007-05-08 00:28:26 -0700678 t0 = ktime_get();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679 }
680
Andrew Mortonc1cda482006-03-25 03:07:15 -0800681 result = (*call)();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682
Ingo Molnar8f0c45c2007-05-08 00:28:26 -0700683 if (initcall_debug) {
684 t1 = ktime_get();
685 delta = ktime_sub(t1, t0);
686
687 printk("initcall 0x%p", *call);
688 print_fn_descriptor_symbol(": %s()",
689 (unsigned long) *call);
690 printk(" returned %d.\n", result);
691
692 printk("initcall 0x%p ran for %Ld msecs: ",
693 *call, (unsigned long long)delta.tv64 >> 20);
694 print_fn_descriptor_symbol("%s()\n",
695 (unsigned long) *call);
696 }
697
Andrew Mortonf3a19cb2006-05-01 12:15:52 -0700698 if (result && result != -ENODEV && initcall_debug) {
Andrew Mortonc1cda482006-03-25 03:07:15 -0800699 sprintf(msgbuf, "error code %d", result);
700 msg = msgbuf;
701 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702 if (preempt_count() != count) {
703 msg = "preemption imbalance";
704 preempt_count() = count;
705 }
706 if (irqs_disabled()) {
707 msg = "disabled interrupts";
708 local_irq_enable();
709 }
710 if (msg) {
Andrew Mortonc1cda482006-03-25 03:07:15 -0800711 printk(KERN_WARNING "initcall at 0x%p", *call);
712 print_fn_descriptor_symbol(": %s()",
713 (unsigned long) *call);
714 printk(": returned with %s\n", msg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715 }
716 }
717
718 /* Make sure there is no pending stuff from the initcall sequence */
719 flush_scheduled_work();
720}
721
722/*
723 * Ok, the machine is now initialized. None of the devices
724 * have been touched yet, but the CPU subsystem is up and
725 * running, and memory and process management works.
726 *
727 * Now we can finally start doing some real work..
728 */
729static void __init do_basic_setup(void)
730{
731 /* drivers will send hotplug events */
732 init_workqueues();
733 usermodehelper_init();
734 driver_init();
Eric W. Biedermanb04c3af2007-02-14 00:33:57 -0800735 init_irq_proc();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736 do_initcalls();
737}
738
Dave Jones97842212007-07-15 23:41:05 -0700739static int __initdata nosoftlockup;
740
741static int __init nosoftlockup_setup(char *str)
742{
743 nosoftlockup = 1;
744 return 1;
745}
746__setup("nosoftlockup", nosoftlockup_setup);
747
Vivek Goyal88d20322007-01-11 01:52:44 +0100748static void __init do_pre_smp_initcalls(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749{
750 extern int spawn_ksoftirqd(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751
752 migration_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753 spawn_ksoftirqd();
Dave Jones97842212007-07-15 23:41:05 -0700754 if (!nosoftlockup)
755 spawn_softlockup_task();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756}
757
758static void run_init_process(char *init_filename)
759{
760 argv_init[0] = init_filename;
Arnd Bergmann67608562006-10-02 02:18:26 -0700761 kernel_execve(init_filename, argv_init, envp_init);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762}
763
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100764/* This is a non __init function. Force it to be noinline otherwise gcc
765 * makes it inline to init() and it becomes part of init.text section
766 */
767static int noinline init_post(void)
768{
769 free_initmem();
770 unlock_kernel();
771 mark_rodata_ro();
772 system_state = SYSTEM_RUNNING;
773 numa_default_policy();
774
775 if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
776 printk(KERN_WARNING "Warning: unable to open an initial console.\n");
777
778 (void) sys_dup(0);
779 (void) sys_dup(0);
780
781 if (ramdisk_execute_command) {
782 run_init_process(ramdisk_execute_command);
783 printk(KERN_WARNING "Failed to execute %s\n",
784 ramdisk_execute_command);
785 }
786
787 /*
788 * We try each of these until one succeeds.
789 *
790 * The Bourne shell can be used instead of init if we are
791 * trying to recover a really broken machine.
792 */
793 if (execute_command) {
794 run_init_process(execute_command);
795 printk(KERN_WARNING "Failed to execute %s. Attempting "
796 "defaults...\n", execute_command);
797 }
798 run_init_process("/sbin/init");
799 run_init_process("/etc/init");
800 run_init_process("/bin/init");
801 run_init_process("/bin/sh");
802
803 panic("No init found. Try passing init= option to kernel.");
804}
805
Sam Ravnborgaae5f662007-02-26 16:45:41 +0100806static int __init kernel_init(void * unused)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700807{
808 lock_kernel();
809 /*
810 * init can run on any cpu.
811 */
812 set_cpus_allowed(current, CPU_MASK_ALL);
813 /*
814 * Tell the world that we're going to be the grim
815 * reaper of innocent orphaned children.
816 *
817 * We don't want people to have to make incorrect
818 * assumptions about where in the task array this
819 * can be found.
820 */
Sukadev Bhattiprolu84d73782006-12-08 02:38:01 -0800821 init_pid_ns.child_reaper = current;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822
Sukadev Bhattiprolu0e29b242007-05-10 22:23:01 -0700823 __set_special_pids(1, 1);
Cedric Le Goater9ec52092006-10-02 02:19:00 -0700824 cad_pid = task_pid(current);
825
Linus Torvalds1da177e2005-04-16 15:20:36 -0700826 smp_prepare_cpus(max_cpus);
827
828 do_pre_smp_initcalls();
829
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830 smp_init();
831 sched_init_smp();
832
833 cpuset_init_smp();
834
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835 do_basic_setup();
836
837 /*
838 * check if there is an early userspace init. If yes, let it do all
839 * the work
840 */
Olof Johanssonffdfc402005-09-06 15:17:19 -0700841
842 if (!ramdisk_execute_command)
843 ramdisk_execute_command = "/init";
844
845 if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
846 ramdisk_execute_command = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847 prepare_namespace();
Olof Johanssonffdfc402005-09-06 15:17:19 -0700848 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849
850 /*
851 * Ok, we have completed the initial bootup, and
852 * we're essentially up and running. Get rid of the
853 * initmem segments and start the user-mode stuff..
854 */
Vivek Goyalee5bfa62007-02-13 13:26:22 +0100855 init_post();
856 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857}