blob: 2b1cdaab45e654bd1dd9c7d772c48e226e6ec20d [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>
42#include <linux/efi.h>
Shailabh Nagarc7572492006-07-14 00:24:40 -070043#include <linux/taskstats_kern.h>
Shailabh Nagarca74e922006-07-14 00:24:36 -070044#include <linux/delayacct.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070045#include <linux/unistd.h>
46#include <linux/rmap.h>
47#include <linux/mempolicy.h>
48#include <linux/key.h>
Jan Beulich4552d5d2006-06-26 13:57:28 +020049#include <linux/unwind.h>
Adrian Bunkb6cd0b72006-06-27 02:53:54 -070050#include <linux/buffer_head.h>
Ingo Molnar9a11b49a2006-07-03 00:24:33 -070051#include <linux/debug_locks.h>
Ingo Molnarfbb9ce92006-07-03 00:24:50 -070052#include <linux/lockdep.h>
Herbert Poetzla2ee8642006-12-08 02:36:00 -080053#include <linux/utsrelease.h>
Sukadev Bhattiprolu84d73782006-12-08 02:38:01 -080054#include <linux/pid_namespace.h>
Herbert Poetzla2ee8642006-12-08 02:36:00 -080055#include <linux/compile.h>
Adrian Bunk1f217822006-12-19 13:01:28 -080056#include <linux/device.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
58#include <asm/io.h>
59#include <asm/bugs.h>
60#include <asm/setup.h>
Andi Kleena9401992005-07-28 21:15:30 -070061#include <asm/sections.h>
Arjan van de Ven37b73c82006-01-06 00:12:01 -080062#include <asm/cacheflush.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070063
Linus Torvalds1da177e2005-04-16 15:20:36 -070064#ifdef CONFIG_X86_LOCAL_APIC
65#include <asm/smp.h>
66#endif
67
68/*
Coywolf Qi Hunt69c99ac2006-01-14 13:21:11 -080069 * This is one of the first .c files built. Error out early if we have compiler
70 * trouble.
71 *
72 * Versions of gcc older than that listed below may actually compile and link
73 * okay, but the end product can have subtle run time bugs. To avoid associated
74 * bogus bug reports, we flatly refuse to compile with a gcc that is known to be
75 * too old from the very beginning.
Linus Torvalds1da177e2005-04-16 15:20:36 -070076 */
Andrew Mortonfd285bb2006-01-08 01:04:07 -080077#if (__GNUC__ < 3) || (__GNUC__ == 3 && __GNUC_MINOR__ < 2)
Linus Torvalds1da177e2005-04-16 15:20:36 -070078#error Sorry, your GCC is too old. It builds incorrect kernels.
79#endif
80
Andrew Mortonf1a60db2006-12-06 20:39:59 -080081#if __GNUC__ == 4 && __GNUC_MINOR__ == 1 && __GNUC_PATCHLEVEL__ == 0
82#warning gcc-4.1.0 is known to miscompile the kernel. A different compiler version is recommended.
83#endif
84
Linus Torvalds1da177e2005-04-16 15:20:36 -070085static int init(void *);
86
87extern void init_IRQ(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070088extern void fork_init(unsigned long);
89extern void mca_init(void);
90extern void sbus_init(void);
91extern void sysctl_init(void);
92extern void signals_init(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070093extern void pidhash_init(void);
94extern void pidmap_init(void);
95extern void prio_tree_init(void);
96extern void radix_tree_init(void);
97extern void free_initmem(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070098extern void prepare_namespace(void);
99#ifdef CONFIG_ACPI
100extern void acpi_early_init(void);
101#else
102static inline void acpi_early_init(void) { }
103#endif
Arjan van de Ven37b73c82006-01-06 00:12:01 -0800104#ifndef CONFIG_DEBUG_RODATA
105static inline void mark_rodata_ro(void) { }
106#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107
108#ifdef CONFIG_TC
109extern void tc_init(void);
110#endif
111
112enum system_states system_state;
113EXPORT_SYMBOL(system_state);
114
115/*
116 * Boot command-line arguments
117 */
118#define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
119#define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
120
121extern void time_init(void);
122/* Default late time init is NULL. archs can override this later. */
123void (*late_time_init)(void);
124extern void softirq_init(void);
125
126/* Untouched command line (eg. for /proc) saved by arch-specific code. */
127char saved_command_line[COMMAND_LINE_SIZE];
128
129static char *execute_command;
Olof Johanssonffdfc402005-09-06 15:17:19 -0700130static char *ramdisk_execute_command;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131
132/* Setup configured maximum number of CPUs to activate */
133static unsigned int max_cpus = NR_CPUS;
134
135/*
Vivek Goyal7e962872006-09-27 01:50:44 -0700136 * If set, this is an indication to the drivers that reset the underlying
137 * device before going ahead with the initialization otherwise driver might
138 * rely on the BIOS and skip the reset operation.
139 *
140 * This is useful if kernel is booting in an unreliable environment.
141 * For ex. kdump situaiton where previous kernel has crashed, BIOS has been
142 * skipped and devices will be in unknown state.
143 */
144unsigned int reset_devices;
145EXPORT_SYMBOL(reset_devices);
146
147/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148 * Setup routine for controlling SMP activation
149 *
150 * Command-line option of "nosmp" or "maxcpus=0" will disable SMP
151 * activation entirely (the MPS table probe still happens, though).
152 *
153 * Command-line option of "maxcpus=<NUM>", where <NUM> is an integer
154 * greater than 0, limits the maximum number of CPUs activated in
155 * SMP mode to <NUM>.
156 */
157static int __init nosmp(char *str)
158{
159 max_cpus = 0;
160 return 1;
161}
162
163__setup("nosmp", nosmp);
164
165static int __init maxcpus(char *str)
166{
167 get_option(&str, &max_cpus);
168 return 1;
169}
170
171__setup("maxcpus=", maxcpus);
172
Vivek Goyal7e962872006-09-27 01:50:44 -0700173static int __init set_reset_devices(char *str)
174{
175 reset_devices = 1;
176 return 1;
177}
178
179__setup("reset_devices", set_reset_devices);
180
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181static char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
182char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
183static const char *panic_later, *panic_param;
184
185extern struct obs_kernel_param __setup_start[], __setup_end[];
186
187static int __init obsolete_checksetup(char *line)
188{
189 struct obs_kernel_param *p;
Rusty Russell33df0d12006-09-26 10:52:32 +0200190 int had_early_param = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191
192 p = __setup_start;
193 do {
194 int n = strlen(p->str);
195 if (!strncmp(line, p->str, n)) {
196 if (p->early) {
Rusty Russell33df0d12006-09-26 10:52:32 +0200197 /* Already done in parse_early_param?
198 * (Needs exact match on param part).
199 * Keep iterating, as we can have early
200 * params and __setups of same names 8( */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 if (line[n] == '\0' || line[n] == '=')
Rusty Russell33df0d12006-09-26 10:52:32 +0200202 had_early_param = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203 } else if (!p->setup_func) {
204 printk(KERN_WARNING "Parameter %s is obsolete,"
205 " ignored\n", p->str);
206 return 1;
207 } else if (p->setup_func(line + n))
208 return 1;
209 }
210 p++;
211 } while (p < __setup_end);
Rusty Russell33df0d12006-09-26 10:52:32 +0200212
213 return had_early_param;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214}
215
216/*
217 * This should be approx 2 Bo*oMips to start (note initial shift), and will
218 * still work even if initially too large, it will just take slightly longer
219 */
220unsigned long loops_per_jiffy = (1<<12);
221
222EXPORT_SYMBOL(loops_per_jiffy);
223
224static int __init debug_kernel(char *str)
225{
226 if (*str)
227 return 0;
228 console_loglevel = 10;
229 return 1;
230}
231
232static int __init quiet_kernel(char *str)
233{
234 if (*str)
235 return 0;
236 console_loglevel = 4;
237 return 1;
238}
239
240__setup("debug", debug_kernel);
241__setup("quiet", quiet_kernel);
242
243static int __init loglevel(char *str)
244{
245 get_option(&str, &console_loglevel);
246 return 1;
247}
248
249__setup("loglevel=", loglevel);
250
251/*
252 * Unknown boot options get handed to init, unless they look like
253 * failed parameters
254 */
255static int __init unknown_bootoption(char *param, char *val)
256{
257 /* Change NUL term back to "=", to make "param" the whole string. */
258 if (val) {
259 /* param=val or param="val"? */
260 if (val == param+strlen(param)+1)
261 val[-1] = '=';
262 else if (val == param+strlen(param)+2) {
263 val[-2] = '=';
264 memmove(val-1, val, strlen(val)+1);
265 val--;
266 } else
267 BUG();
268 }
269
270 /* Handle obsolete-style parameters */
271 if (obsolete_checksetup(param))
272 return 0;
273
274 /*
275 * Preemptive maintenance for "why didn't my mispelled command
276 * line work?"
277 */
278 if (strchr(param, '.') && (!val || strchr(param, '.') < val)) {
279 printk(KERN_ERR "Unknown boot option `%s': ignoring\n", param);
280 return 0;
281 }
282
283 if (panic_later)
284 return 0;
285
286 if (val) {
287 /* Environment option */
288 unsigned int i;
289 for (i = 0; envp_init[i]; i++) {
290 if (i == MAX_INIT_ENVS) {
291 panic_later = "Too many boot env vars at `%s'";
292 panic_param = param;
293 }
294 if (!strncmp(param, envp_init[i], val - param))
295 break;
296 }
297 envp_init[i] = param;
298 } else {
299 /* Command line option */
300 unsigned int i;
301 for (i = 0; argv_init[i]; i++) {
302 if (i == MAX_INIT_ARGS) {
303 panic_later = "Too many boot init vars at `%s'";
304 panic_param = param;
305 }
306 }
307 argv_init[i] = param;
308 }
309 return 0;
310}
311
312static int __init init_setup(char *str)
313{
314 unsigned int i;
315
316 execute_command = str;
317 /*
318 * In case LILO is going to boot us with default command line,
319 * it prepends "auto" before the whole cmdline which makes
320 * the shell think it should execute a script with such name.
321 * So we ignore all arguments entered _before_ init=... [MJ]
322 */
323 for (i = 1; i < MAX_INIT_ARGS; i++)
324 argv_init[i] = NULL;
325 return 1;
326}
327__setup("init=", init_setup);
328
Olof Johanssonffdfc402005-09-06 15:17:19 -0700329static int __init rdinit_setup(char *str)
330{
331 unsigned int i;
332
333 ramdisk_execute_command = str;
334 /* See "auto" comment in init_setup */
335 for (i = 1; i < MAX_INIT_ARGS; i++)
336 argv_init[i] = NULL;
337 return 1;
338}
339__setup("rdinit=", rdinit_setup);
340
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341#ifndef CONFIG_SMP
342
343#ifdef CONFIG_X86_LOCAL_APIC
344static void __init smp_init(void)
345{
346 APIC_init_uniprocessor();
347}
348#else
349#define smp_init() do { } while (0)
350#endif
351
352static inline void setup_per_cpu_areas(void) { }
353static inline void smp_prepare_cpus(unsigned int maxcpus) { }
354
355#else
356
357#ifdef __GENERIC_PER_CPU
Eric Dumazetb73b4592006-03-23 03:01:07 -0800358unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359
360EXPORT_SYMBOL(__per_cpu_offset);
361
362static void __init setup_per_cpu_areas(void)
363{
364 unsigned long size, i;
365 char *ptr;
Eric Dumazet63872f82006-03-23 03:01:04 -0800366 unsigned long nr_possible_cpus = num_possible_cpus();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367
368 /* Copy section for each CPU (we discard the original) */
369 size = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES);
370#ifdef CONFIG_MODULES
371 if (size < PERCPU_ENOUGH_ROOM)
372 size = PERCPU_ENOUGH_ROOM;
373#endif
Eric Dumazet63872f82006-03-23 03:01:04 -0800374 ptr = alloc_bootmem(size * nr_possible_cpus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375
KAMEZAWA Hiroyuki0a945022006-03-28 01:56:37 -0800376 for_each_possible_cpu(i) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377 __per_cpu_offset[i] = ptr - __per_cpu_start;
378 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
Eric Dumazet63872f82006-03-23 03:01:04 -0800379 ptr += size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380 }
381}
382#endif /* !__GENERIC_PER_CPU */
383
384/* Called by boot processor to activate the rest. */
385static void __init smp_init(void)
386{
387 unsigned int i;
388
389 /* FIXME: This should be done in userspace --RR */
390 for_each_present_cpu(i) {
391 if (num_online_cpus() >= max_cpus)
392 break;
393 if (!cpu_online(i))
394 cpu_up(i);
395 }
396
397 /* Any cleanup work */
398 printk(KERN_INFO "Brought up %ld CPUs\n", (long)num_online_cpus());
399 smp_cpus_done(max_cpus);
400#if 0
401 /* Get other processors into their bootup holding patterns. */
402
403 smp_commence();
404#endif
405}
406
407#endif
408
409/*
410 * We need to finalize in a non-__init function or else race conditions
411 * between the root thread and the init thread may cause start_kernel to
412 * be reaped by free_initmem before the root thread has proceeded to
413 * cpu_idle.
414 *
415 * gcc-3.4 accidentally inlines this function, so use noinline.
416 */
417
418static void noinline rest_init(void)
419 __releases(kernel_lock)
420{
421 kernel_thread(init, NULL, CLONE_FS | CLONE_SIGHAND);
422 numa_default_policy();
423 unlock_kernel();
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200424
425 /*
426 * The boot idle thread must execute schedule()
427 * at least one to get things moving:
428 */
Nick Piggin5bfb5d62005-11-08 21:39:01 -0800429 preempt_enable_no_resched();
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200430 schedule();
Nick Piggin5bfb5d62005-11-08 21:39:01 -0800431 preempt_disable();
Ingo Molnarf340c0d2005-06-28 16:40:42 +0200432
Nick Piggin5bfb5d62005-11-08 21:39:01 -0800433 /* Call into cpu_idle with preempt disabled */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434 cpu_idle();
435}
436
437/* Check for early params. */
438static int __init do_early_param(char *param, char *val)
439{
440 struct obs_kernel_param *p;
441
442 for (p = __setup_start; p < __setup_end; p++) {
443 if (p->early && strcmp(param, p->str) == 0) {
444 if (p->setup_func(val) != 0)
445 printk(KERN_WARNING
446 "Malformed early option '%s'\n", param);
447 }
448 }
449 /* We accept everything at this stage. */
450 return 0;
451}
452
453/* Arch code calls this early on, or if not, just before other parsing. */
454void __init parse_early_param(void)
455{
456 static __initdata int done = 0;
457 static __initdata char tmp_cmdline[COMMAND_LINE_SIZE];
458
459 if (done)
460 return;
461
462 /* All fall through to do_early_param. */
463 strlcpy(tmp_cmdline, saved_command_line, COMMAND_LINE_SIZE);
464 parse_args("early options", tmp_cmdline, NULL, 0, do_early_param);
465 done = 1;
466}
467
468/*
469 * Activate the first processor.
470 */
471
Stas Sergeev44fd2292006-03-23 02:59:44 -0800472static void __init boot_cpu_init(void)
473{
474 int cpu = smp_processor_id();
475 /* Mark the boot cpu "present", "online" etc for SMP and UP case */
476 cpu_set(cpu, cpu_online_map);
477 cpu_set(cpu, cpu_present_map);
478 cpu_set(cpu, cpu_possible_map);
479}
480
Andrew Morton033ab7f2006-06-30 01:55:50 -0700481void __init __attribute__((weak)) smp_setup_processor_id(void)
482{
483}
484
Linus Torvalds89937802006-12-11 09:28:46 -0800485static const char linux_banner[] =
486 "Linux version " UTS_RELEASE
487 " (" LINUX_COMPILE_BY "@" LINUX_COMPILE_HOST ")"
488 " (" LINUX_COMPILER ")"
489 " " UTS_VERSION "\n";
490
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491asmlinkage void __init start_kernel(void)
492{
493 char * command_line;
494 extern struct kernel_param __start___param[], __stop___param[];
Andrew Morton033ab7f2006-06-30 01:55:50 -0700495
496 smp_setup_processor_id();
497
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700498 /*
499 * Need to run as early as possible, to initialize the
500 * lockdep hash:
501 */
Andi Kleenc9538ed2006-09-26 10:52:34 +0200502 unwind_init();
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700503 lockdep_init();
504
505 local_irq_disable();
506 early_boot_irqs_off();
Ingo Molnar243c7622006-07-03 00:25:06 -0700507 early_init_irq_lock_class();
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700508
Linus Torvalds1da177e2005-04-16 15:20:36 -0700509/*
510 * Interrupts are still disabled. Do necessary setups, then
511 * enable them
512 */
513 lock_kernel();
Stas Sergeev44fd2292006-03-23 02:59:44 -0800514 boot_cpu_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700515 page_address_init();
516 printk(KERN_NOTICE);
Linus Torvalds89937802006-12-11 09:28:46 -0800517 printk(linux_banner);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518 setup_arch(&command_line);
Jan Beulich690a9732006-10-21 18:37:01 +0200519 unwind_setup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 setup_per_cpu_areas();
Stas Sergeev44fd2292006-03-23 02:59:44 -0800521 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522
523 /*
524 * Set up the scheduler prior starting any interrupts (such as the
525 * timer interrupt). Full topology setup happens at smp_init()
526 * time - but meanwhile we still have a functioning scheduler.
527 */
528 sched_init();
529 /*
530 * Disable preemption - early bootup scheduling is extremely
531 * fragile until we cpu_idle() for the first time.
532 */
533 preempt_disable();
534 build_all_zonelists();
535 page_alloc_init();
536 printk(KERN_NOTICE "Kernel command line: %s\n", saved_command_line);
537 parse_early_param();
538 parse_args("Booting kernel", command_line, __start___param,
539 __stop___param - __start___param,
540 &unknown_bootoption);
541 sort_main_extable();
542 trap_init();
543 rcu_init();
544 init_IRQ();
545 pidhash_init();
546 init_timers();
Thomas Gleixnerc0a31322006-01-09 20:52:32 -0800547 hrtimers_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548 softirq_init();
john stultzad596172006-06-26 00:25:06 -0700549 timekeeping_init();
john stultz88fecaa2006-07-03 00:24:04 -0700550 time_init();
Heiko Carstens93e02812006-07-03 00:24:24 -0700551 profile_init();
552 if (!irqs_disabled())
553 printk("start_kernel(): bug: interrupts were enabled early\n");
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700554 early_boot_irqs_on();
Heiko Carstens93e02812006-07-03 00:24:24 -0700555 local_irq_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556
557 /*
558 * HACK ALERT! This is early. We're enabling the console before
559 * we've done PCI setups etc, and console_init() must be aware of
560 * this. But we do want output early, in case something goes wrong.
561 */
562 console_init();
563 if (panic_later)
564 panic(panic_later, panic_param);
Ingo Molnarfbb9ce92006-07-03 00:24:50 -0700565
566 lockdep_info();
567
Ingo Molnar9a11b49a2006-07-03 00:24:33 -0700568 /*
569 * Need to run this when irqs are enabled, because it wants
570 * to self-test [hard/soft]-irqs on/off lock inversion bugs
571 * too:
572 */
573 locking_selftest();
574
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575#ifdef CONFIG_BLK_DEV_INITRD
576 if (initrd_start && !initrd_below_start_ok &&
577 initrd_start < min_low_pfn << PAGE_SHIFT) {
578 printk(KERN_CRIT "initrd overwritten (0x%08lx < 0x%08lx) - "
579 "disabling it.\n",initrd_start,min_low_pfn << PAGE_SHIFT);
580 initrd_start = 0;
581 }
582#endif
583 vfs_caches_init_early();
Paul Jacksonc417f022006-01-08 01:02:01 -0800584 cpuset_init_early();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585 mem_init();
586 kmem_cache_init();
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700587 setup_per_cpu_pageset();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588 numa_policy_init();
589 if (late_time_init)
590 late_time_init();
591 calibrate_delay();
592 pidmap_init();
593 pgtable_cache_init();
594 prio_tree_init();
595 anon_vma_init();
596#ifdef CONFIG_X86
597 if (efi_enabled)
598 efi_enter_virtual_mode();
599#endif
600 fork_init(num_physpages);
601 proc_caches_init();
602 buffer_init();
603 unnamed_dev_init();
604 key_init();
605 security_init();
606 vfs_caches_init(num_physpages);
607 radix_tree_init();
608 signals_init();
609 /* rootfs populating might need page-writeback */
610 page_writeback_init();
611#ifdef CONFIG_PROC_FS
612 proc_root_init();
613#endif
614 cpuset_init();
Shailabh Nagarc7572492006-07-14 00:24:40 -0700615 taskstats_init_early();
Shailabh Nagarca74e922006-07-14 00:24:36 -0700616 delayacct_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617
618 check_bugs();
619
620 acpi_early_init(); /* before LAPIC and SMP init */
621
622 /* Do the rest non-__init'ed, we're now alive */
623 rest_init();
624}
625
626static int __initdata initcall_debug;
627
628static int __init initcall_debug_setup(char *str)
629{
630 initcall_debug = 1;
631 return 1;
632}
633__setup("initcall_debug", initcall_debug_setup);
634
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635extern initcall_t __initcall_start[], __initcall_end[];
636
637static void __init do_initcalls(void)
638{
639 initcall_t *call;
640 int count = preempt_count();
641
642 for (call = __initcall_start; call < __initcall_end; call++) {
Andrew Mortonc1cda482006-03-25 03:07:15 -0800643 char *msg = NULL;
644 char msgbuf[40];
645 int result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646
647 if (initcall_debug) {
Andrew Mortonc1cda482006-03-25 03:07:15 -0800648 printk("Calling initcall 0x%p", *call);
649 print_fn_descriptor_symbol(": %s()",
650 (unsigned long) *call);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651 printk("\n");
652 }
653
Andrew Mortonc1cda482006-03-25 03:07:15 -0800654 result = (*call)();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700655
Andrew Mortonf3a19cb2006-05-01 12:15:52 -0700656 if (result && result != -ENODEV && initcall_debug) {
Andrew Mortonc1cda482006-03-25 03:07:15 -0800657 sprintf(msgbuf, "error code %d", result);
658 msg = msgbuf;
659 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660 if (preempt_count() != count) {
661 msg = "preemption imbalance";
662 preempt_count() = count;
663 }
664 if (irqs_disabled()) {
665 msg = "disabled interrupts";
666 local_irq_enable();
667 }
668 if (msg) {
Andrew Mortonc1cda482006-03-25 03:07:15 -0800669 printk(KERN_WARNING "initcall at 0x%p", *call);
670 print_fn_descriptor_symbol(": %s()",
671 (unsigned long) *call);
672 printk(": returned with %s\n", msg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673 }
674 }
675
676 /* Make sure there is no pending stuff from the initcall sequence */
677 flush_scheduled_work();
678}
679
680/*
681 * Ok, the machine is now initialized. None of the devices
682 * have been touched yet, but the CPU subsystem is up and
683 * running, and memory and process management works.
684 *
685 * Now we can finally start doing some real work..
686 */
687static void __init do_basic_setup(void)
688{
689 /* drivers will send hotplug events */
690 init_workqueues();
691 usermodehelper_init();
692 driver_init();
693
694#ifdef CONFIG_SYSCTL
695 sysctl_init();
696#endif
697
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698 do_initcalls();
699}
700
701static void do_pre_smp_initcalls(void)
702{
703 extern int spawn_ksoftirqd(void);
704#ifdef CONFIG_SMP
705 extern int migration_init(void);
706
707 migration_init();
708#endif
709 spawn_ksoftirqd();
Ingo Molnar8446f1d2005-09-06 15:16:27 -0700710 spawn_softlockup_task();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711}
712
713static void run_init_process(char *init_filename)
714{
715 argv_init[0] = init_filename;
Arnd Bergmann67608562006-10-02 02:18:26 -0700716 kernel_execve(init_filename, argv_init, envp_init);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717}
718
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719static int init(void * unused)
720{
721 lock_kernel();
722 /*
723 * init can run on any cpu.
724 */
725 set_cpus_allowed(current, CPU_MASK_ALL);
726 /*
727 * Tell the world that we're going to be the grim
728 * reaper of innocent orphaned children.
729 *
730 * We don't want people to have to make incorrect
731 * assumptions about where in the task array this
732 * can be found.
733 */
Sukadev Bhattiprolu84d73782006-12-08 02:38:01 -0800734 init_pid_ns.child_reaper = current;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735
Cedric Le Goater9ec52092006-10-02 02:19:00 -0700736 cad_pid = task_pid(current);
737
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738 smp_prepare_cpus(max_cpus);
739
740 do_pre_smp_initcalls();
741
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742 smp_init();
743 sched_init_smp();
744
745 cpuset_init_smp();
746
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747 do_basic_setup();
748
749 /*
750 * check if there is an early userspace init. If yes, let it do all
751 * the work
752 */
Olof Johanssonffdfc402005-09-06 15:17:19 -0700753
754 if (!ramdisk_execute_command)
755 ramdisk_execute_command = "/init";
756
757 if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
758 ramdisk_execute_command = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759 prepare_namespace();
Olof Johanssonffdfc402005-09-06 15:17:19 -0700760 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761
762 /*
763 * Ok, we have completed the initial bootup, and
764 * we're essentially up and running. Get rid of the
765 * initmem segments and start the user-mode stuff..
766 */
767 free_initmem();
768 unlock_kernel();
Arjan van de Ven37b73c82006-01-06 00:12:01 -0800769 mark_rodata_ro();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700770 system_state = SYSTEM_RUNNING;
771 numa_default_policy();
772
773 if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
774 printk(KERN_WARNING "Warning: unable to open an initial console.\n");
775
776 (void) sys_dup(0);
777 (void) sys_dup(0);
Olof Johanssonffdfc402005-09-06 15:17:19 -0700778
779 if (ramdisk_execute_command) {
780 run_init_process(ramdisk_execute_command);
781 printk(KERN_WARNING "Failed to execute %s\n",
782 ramdisk_execute_command);
783 }
784
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785 /*
786 * We try each of these until one succeeds.
787 *
788 * The Bourne shell can be used instead of init if we are
789 * trying to recover a really broken machine.
790 */
Avery, Brianc1d7ef72005-09-06 15:16:56 -0700791 if (execute_command) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792 run_init_process(execute_command);
Avery, Brianc1d7ef72005-09-06 15:16:56 -0700793 printk(KERN_WARNING "Failed to execute %s. Attempting "
794 "defaults...\n", execute_command);
795 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796 run_init_process("/sbin/init");
797 run_init_process("/etc/init");
798 run_init_process("/bin/init");
799 run_init_process("/bin/sh");
800
801 panic("No init found. Try passing init= option to kernel.");
802}