infrastructure for saner ret_from_kernel_thread semantics
[deliverable/linux.git] / init / main.c
CommitLineData
1da177e4
LT
1/*
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
1da177e4
LT
12#include <linux/types.h>
13#include <linux/module.h>
14#include <linux/proc_fs.h>
1da177e4
LT
15#include <linux/kernel.h>
16#include <linux/syscalls.h>
9b5609fd 17#include <linux/stackprotector.h>
1da177e4
LT
18#include <linux/string.h>
19#include <linux/ctype.h>
20#include <linux/delay.h>
1da177e4
LT
21#include <linux/ioport.h>
22#include <linux/init.h>
1da177e4 23#include <linux/initrd.h>
1da177e4 24#include <linux/bootmem.h>
4a7a16dc 25#include <linux/acpi.h>
1da177e4 26#include <linux/tty.h>
1da177e4
LT
27#include <linux/percpu.h>
28#include <linux/kmod.h>
db64fe02 29#include <linux/vmalloc.h>
1da177e4 30#include <linux/kernel_stat.h>
d7cd5611 31#include <linux/start_kernel.h>
1da177e4 32#include <linux/security.h>
3d442233 33#include <linux/smp.h>
1da177e4
LT
34#include <linux/profile.h>
35#include <linux/rcupdate.h>
36#include <linux/moduleparam.h>
37#include <linux/kallsyms.h>
38#include <linux/writeback.h>
39#include <linux/cpu.h>
40#include <linux/cpuset.h>
ddbcc7e8 41#include <linux/cgroup.h>
1da177e4 42#include <linux/efi.h>
906568c9 43#include <linux/tick.h>
6168a702 44#include <linux/interrupt.h>
c757249a 45#include <linux/taskstats_kern.h>
ca74e92b 46#include <linux/delayacct.h>
1da177e4
LT
47#include <linux/unistd.h>
48#include <linux/rmap.h>
49#include <linux/mempolicy.h>
50#include <linux/key.h>
b6cd0b77 51#include <linux/buffer_head.h>
94b6da5a 52#include <linux/page_cgroup.h>
9a11b49a 53#include <linux/debug_locks.h>
3ac7fe5a 54#include <linux/debugobjects.h>
fbb9ce95 55#include <linux/lockdep.h>
3c7b4e6b 56#include <linux/kmemleak.h>
84d73786 57#include <linux/pid_namespace.h>
1f21782e 58#include <linux/device.h>
73c27992 59#include <linux/kthread.h>
e6fe6649 60#include <linux/sched.h>
a1c9eea9 61#include <linux/signal.h>
199f0ca5 62#include <linux/idr.h>
0b4b3827 63#include <linux/kgdb.h>
68bf21aa 64#include <linux/ftrace.h>
22a9d645 65#include <linux/async.h>
dfec072e 66#include <linux/kmemcheck.h>
6ae6996a 67#include <linux/sfi.h>
2b2af54a 68#include <linux/shmem_fs.h>
5a0e3ad6 69#include <linux/slab.h>
24a24bb6 70#include <linux/perf_event.h>
4a9d4b02 71#include <linux/file.h>
a74fb73c 72#include <linux/ptrace.h>
1da177e4
LT
73
74#include <asm/io.h>
75#include <asm/bugs.h>
76#include <asm/setup.h>
a940199f 77#include <asm/sections.h>
37b73c82 78#include <asm/cacheflush.h>
1da177e4 79
1da177e4
LT
80#ifdef CONFIG_X86_LOCAL_APIC
81#include <asm/smp.h>
82#endif
83
aae5f662 84static int kernel_init(void *);
1da177e4
LT
85
86extern void init_IRQ(void);
1da177e4
LT
87extern void fork_init(unsigned long);
88extern void mca_init(void);
89extern void sbus_init(void);
1da177e4
LT
90extern void prio_tree_init(void);
91extern void radix_tree_init(void);
37b73c82
AV
92#ifndef CONFIG_DEBUG_RODATA
93static inline void mark_rodata_ro(void) { }
94#endif
1da177e4
LT
95
96#ifdef CONFIG_TC
97extern void tc_init(void);
98#endif
99
2ce802f6
TH
100/*
101 * Debug helper: via this flag we know that we are in 'early bootup code'
102 * where only the boot processor is running with IRQ disabled. This means
103 * two things - IRQ must not be enabled before the flag is cleared and some
104 * operations which are not allowed with IRQ disabled are allowed while the
105 * flag is set.
106 */
107bool early_boot_irqs_disabled __read_mostly;
108
a6826048 109enum system_states system_state __read_mostly;
1da177e4
LT
110EXPORT_SYMBOL(system_state);
111
112/*
113 * Boot command-line arguments
114 */
115#define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
116#define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
117
118extern void time_init(void);
119/* Default late time init is NULL. archs can override this later. */
d2e3192b 120void (*__initdata late_time_init)(void);
1da177e4
LT
121extern void softirq_init(void);
122
30d7e0d4
ABL
123/* Untouched command line saved by arch-specific code. */
124char __initdata boot_command_line[COMMAND_LINE_SIZE];
125/* Untouched saved command line (eg. for /proc) */
126char *saved_command_line;
127/* Command line for parameter parsing */
128static char *static_command_line;
1da177e4
LT
129
130static char *execute_command;
ffdfc409 131static char *ramdisk_execute_command;
1da177e4 132
8b3b2955
JB
133/*
134 * If set, this is an indication to the drivers that reset the underlying
135 * device before going ahead with the initialization otherwise driver might
136 * rely on the BIOS and skip the reset operation.
137 *
138 * This is useful if kernel is booting in an unreliable environment.
139 * For ex. kdump situaiton where previous kernel has crashed, BIOS has been
140 * skipped and devices will be in unknown state.
141 */
142unsigned int reset_devices;
143EXPORT_SYMBOL(reset_devices);
1da177e4 144
7e96287d
VG
145static int __init set_reset_devices(char *str)
146{
147 reset_devices = 1;
148 return 1;
149}
150
151__setup("reset_devices", set_reset_devices);
152
d7627467
DH
153static const char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
154const char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
1da177e4
LT
155static const char *panic_later, *panic_param;
156
914dcaa8 157extern const struct obs_kernel_param __setup_start[], __setup_end[];
1da177e4
LT
158
159static int __init obsolete_checksetup(char *line)
160{
914dcaa8 161 const struct obs_kernel_param *p;
33df0d19 162 int had_early_param = 0;
1da177e4
LT
163
164 p = __setup_start;
165 do {
166 int n = strlen(p->str);
b1e4d20c 167 if (parameqn(line, p->str, n)) {
1da177e4 168 if (p->early) {
33df0d19
RR
169 /* Already done in parse_early_param?
170 * (Needs exact match on param part).
171 * Keep iterating, as we can have early
172 * params and __setups of same names 8( */
1da177e4 173 if (line[n] == '\0' || line[n] == '=')
33df0d19 174 had_early_param = 1;
1da177e4
LT
175 } else if (!p->setup_func) {
176 printk(KERN_WARNING "Parameter %s is obsolete,"
177 " ignored\n", p->str);
178 return 1;
179 } else if (p->setup_func(line + n))
180 return 1;
181 }
182 p++;
183 } while (p < __setup_end);
33df0d19
RR
184
185 return had_early_param;
1da177e4
LT
186}
187
188/*
189 * This should be approx 2 Bo*oMips to start (note initial shift), and will
190 * still work even if initially too large, it will just take slightly longer
191 */
192unsigned long loops_per_jiffy = (1<<12);
193
194EXPORT_SYMBOL(loops_per_jiffy);
195
196static int __init debug_kernel(char *str)
197{
1da177e4 198 console_loglevel = 10;
f6f21c81 199 return 0;
1da177e4
LT
200}
201
202static int __init quiet_kernel(char *str)
203{
1da177e4 204 console_loglevel = 4;
f6f21c81 205 return 0;
1da177e4
LT
206}
207
f6f21c81
YL
208early_param("debug", debug_kernel);
209early_param("quiet", quiet_kernel);
1da177e4
LT
210
211static int __init loglevel(char *str)
212{
808bf29b
AS
213 int newlevel;
214
215 /*
216 * Only update loglevel value when a correct setting was passed,
217 * to prevent blind crashes (when loglevel being set to 0) that
218 * are quite hard to debug
219 */
220 if (get_option(&str, &newlevel)) {
221 console_loglevel = newlevel;
222 return 0;
223 }
224
225 return -EINVAL;
1da177e4
LT
226}
227
f6f21c81 228early_param("loglevel", loglevel);
1da177e4 229
a99cd112 230/* Change NUL term back to "=", to make "param" the whole string. */
eb157427 231static int __init repair_env_string(char *param, char *val, const char *unused)
1da177e4 232{
1da177e4
LT
233 if (val) {
234 /* param=val or param="val"? */
235 if (val == param+strlen(param)+1)
236 val[-1] = '=';
237 else if (val == param+strlen(param)+2) {
238 val[-2] = '=';
239 memmove(val-1, val, strlen(val)+1);
240 val--;
241 } else
242 BUG();
243 }
a99cd112
CM
244 return 0;
245}
246
247/*
248 * Unknown boot options get handed to init, unless they look like
249 * unused parameters (modprobe will find them in /proc/cmdline).
250 */
eb157427 251static int __init unknown_bootoption(char *param, char *val, const char *unused)
a99cd112 252{
eb157427 253 repair_env_string(param, val, unused);
1da177e4
LT
254
255 /* Handle obsolete-style parameters */
256 if (obsolete_checksetup(param))
257 return 0;
258
f066a4f6
RR
259 /* Unused module parameter. */
260 if (strchr(param, '.') && (!val || strchr(param, '.') < val))
1da177e4 261 return 0;
1da177e4
LT
262
263 if (panic_later)
264 return 0;
265
266 if (val) {
267 /* Environment option */
268 unsigned int i;
269 for (i = 0; envp_init[i]; i++) {
270 if (i == MAX_INIT_ENVS) {
271 panic_later = "Too many boot env vars at `%s'";
272 panic_param = param;
273 }
274 if (!strncmp(param, envp_init[i], val - param))
275 break;
276 }
277 envp_init[i] = param;
278 } else {
279 /* Command line option */
280 unsigned int i;
281 for (i = 0; argv_init[i]; i++) {
282 if (i == MAX_INIT_ARGS) {
283 panic_later = "Too many boot init vars at `%s'";
284 panic_param = param;
285 }
286 }
287 argv_init[i] = param;
288 }
289 return 0;
290}
291
292static int __init init_setup(char *str)
293{
294 unsigned int i;
295
296 execute_command = str;
297 /*
298 * In case LILO is going to boot us with default command line,
299 * it prepends "auto" before the whole cmdline which makes
300 * the shell think it should execute a script with such name.
301 * So we ignore all arguments entered _before_ init=... [MJ]
302 */
303 for (i = 1; i < MAX_INIT_ARGS; i++)
304 argv_init[i] = NULL;
305 return 1;
306}
307__setup("init=", init_setup);
308
ffdfc409
OJ
309static int __init rdinit_setup(char *str)
310{
311 unsigned int i;
312
313 ramdisk_execute_command = str;
314 /* See "auto" comment in init_setup */
315 for (i = 1; i < MAX_INIT_ARGS; i++)
316 argv_init[i] = NULL;
317 return 1;
318}
319__setup("rdinit=", rdinit_setup);
320
1da177e4 321#ifndef CONFIG_SMP
34db18a0 322static const unsigned int setup_max_cpus = NR_CPUS;
1da177e4
LT
323#ifdef CONFIG_X86_LOCAL_APIC
324static void __init smp_init(void)
325{
326 APIC_init_uniprocessor();
327}
328#else
329#define smp_init() do { } while (0)
330#endif
331
e0982e90 332static inline void setup_nr_cpu_ids(void) { }
1da177e4 333static inline void smp_prepare_cpus(unsigned int maxcpus) { }
1da177e4
LT
334#endif
335
30d7e0d4
ABL
336/*
337 * We need to store the untouched command line for future reference.
338 * We also need to store the touched command line since the parameter
339 * parsing is performed in place, and we should allow a component to
340 * store reference of name/value for future reference.
341 */
342static void __init setup_command_line(char *command_line)
343{
344 saved_command_line = alloc_bootmem(strlen (boot_command_line)+1);
345 static_command_line = alloc_bootmem(strlen (command_line)+1);
346 strcpy (saved_command_line, boot_command_line);
347 strcpy (static_command_line, command_line);
348}
349
1da177e4
LT
350/*
351 * We need to finalize in a non-__init function or else race conditions
352 * between the root thread and the init thread may cause start_kernel to
353 * be reaped by free_initmem before the root thread has proceeded to
354 * cpu_idle.
355 *
356 * gcc-3.4 accidentally inlines this function, so use noinline.
357 */
358
b433c3d4
PZ
359static __initdata DECLARE_COMPLETION(kthreadd_done);
360
f99ebf0a 361static noinline void __init_refok rest_init(void)
1da177e4 362{
73c27992
EB
363 int pid;
364
7db905e6 365 rcu_scheduler_starting();
b433c3d4 366 /*
97158569 367 * We need to spawn init first so that it obtains pid 1, however
b433c3d4
PZ
368 * the init task will end up wanting to create kthreads, which, if
369 * we schedule it before we create kthreadd, will OOPS.
370 */
aae5f662 371 kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND);
1da177e4 372 numa_default_policy();
73c27992 373 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
d11c563d 374 rcu_read_lock();
5cd20455 375 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
d11c563d 376 rcu_read_unlock();
b433c3d4 377 complete(&kthreadd_done);
f340c0d1
IM
378
379 /*
380 * The boot idle thread must execute schedule()
1df21055 381 * at least once to get things moving:
f340c0d1 382 */
1df21055 383 init_idle_bootup_task(current);
bd2f5536 384 schedule_preempt_disabled();
5bfb5d69 385 /* Call into cpu_idle with preempt disabled */
1da177e4 386 cpu_idle();
1df21055 387}
1da177e4
LT
388
389/* Check for early params. */
9fb48c74 390static int __init do_early_param(char *param, char *val, const char *unused)
1da177e4 391{
914dcaa8 392 const struct obs_kernel_param *p;
1da177e4
LT
393
394 for (p = __setup_start; p < __setup_end; p++) {
b1e4d20c 395 if ((p->early && parameq(param, p->str)) ||
18a8bd94
YL
396 (strcmp(param, "console") == 0 &&
397 strcmp(p->str, "earlycon") == 0)
398 ) {
1da177e4
LT
399 if (p->setup_func(val) != 0)
400 printk(KERN_WARNING
401 "Malformed early option '%s'\n", param);
402 }
403 }
404 /* We accept everything at this stage. */
405 return 0;
406}
407
13977091
MD
408void __init parse_early_options(char *cmdline)
409{
026cee00 410 parse_args("early options", cmdline, NULL, 0, 0, 0, do_early_param);
13977091
MD
411}
412
1da177e4
LT
413/* Arch code calls this early on, or if not, just before other parsing. */
414void __init parse_early_param(void)
415{
416 static __initdata int done = 0;
417 static __initdata char tmp_cmdline[COMMAND_LINE_SIZE];
418
419 if (done)
420 return;
421
422 /* All fall through to do_early_param. */
30d7e0d4 423 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
13977091 424 parse_early_options(tmp_cmdline);
1da177e4
LT
425 done = 1;
426}
427
428/*
429 * Activate the first processor.
430 */
431
44fd2299
SS
432static void __init boot_cpu_init(void)
433{
434 int cpu = smp_processor_id();
435 /* Mark the boot cpu "present", "online" etc for SMP and UP case */
915441b6 436 set_cpu_online(cpu, true);
933b0618 437 set_cpu_active(cpu, true);
915441b6
RR
438 set_cpu_present(cpu, true);
439 set_cpu_possible(cpu, true);
44fd2299
SS
440}
441
839ad62e 442void __init __weak smp_setup_processor_id(void)
033ab7f8
AM
443{
444}
445
8c9843e5
BH
446void __init __weak thread_info_cache_init(void)
447{
448}
449
444f478f
PE
450/*
451 * Set up kernel memory allocators
452 */
453static void __init mm_init(void)
454{
ca371c0d 455 /*
7fa87ce7
JC
456 * page_cgroup requires contiguous pages,
457 * bigger than MAX_ORDER unless SPARSEMEM.
ca371c0d
KH
458 */
459 page_cgroup_init_flatmem();
444f478f
PE
460 mem_init();
461 kmem_cache_init();
099a19d9 462 percpu_init_late();
c868d550 463 pgtable_cache_init();
444f478f
PE
464 vmalloc_init();
465}
466
1da177e4
LT
467asmlinkage void __init start_kernel(void)
468{
469 char * command_line;
914dcaa8 470 extern const struct kernel_param __start___param[], __stop___param[];
033ab7f8 471
fbb9ce95
IM
472 /*
473 * Need to run as early as possible, to initialize the
474 * lockdep hash:
475 */
476 lockdep_init();
73839c5b 477 smp_setup_processor_id();
3ac7fe5a 478 debug_objects_early_init();
42059429
IM
479
480 /*
481 * Set up the the initial canary ASAP:
482 */
483 boot_init_stack_canary();
484
ddbcc7e8 485 cgroup_init_early();
fbb9ce95
IM
486
487 local_irq_disable();
2ce802f6 488 early_boot_irqs_disabled = true;
fbb9ce95 489
1da177e4
LT
490/*
491 * Interrupts are still disabled. Do necessary setups, then
492 * enable them
493 */
906568c9 494 tick_init();
44fd2299 495 boot_cpu_init();
1da177e4 496 page_address_init();
657cafa6 497 printk(KERN_NOTICE "%s", linux_banner);
1da177e4 498 setup_arch(&command_line);
cf475ad2 499 mm_init_owner(&init_mm, &init_task);
6345d24d 500 mm_init_cpumask(&init_mm);
30d7e0d4 501 setup_command_line(command_line);
e0982e90 502 setup_nr_cpu_ids();
d6647bdf 503 setup_per_cpu_areas();
44fd2299 504 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
1da177e4 505
9adb62a5 506 build_all_zonelists(NULL, NULL);
83b519e8
PE
507 page_alloc_init();
508
509 printk(KERN_NOTICE "Kernel command line: %s\n", boot_command_line);
510 parse_early_param();
511 parse_args("Booting kernel", static_command_line, __start___param,
512 __stop___param - __start___param,
ae82fdb1 513 -1, -1, &unknown_bootoption);
97ce2c88
JF
514
515 jump_label_init();
516
83b519e8
PE
517 /*
518 * These use large bootmem allocations and must precede
519 * kmem_cache_init()
520 */
162a7e75 521 setup_log_buf(0);
83b519e8 522 pidhash_init();
83b519e8
PE
523 vfs_caches_init_early();
524 sort_main_extable();
525 trap_init();
444f478f 526 mm_init();
de03c72c 527
1da177e4
LT
528 /*
529 * Set up the scheduler prior starting any interrupts (such as the
530 * timer interrupt). Full topology setup happens at smp_init()
531 * time - but meanwhile we still have a functioning scheduler.
532 */
533 sched_init();
534 /*
535 * Disable preemption - early bootup scheduling is extremely
536 * fragile until we cpu_idle() for the first time.
537 */
538 preempt_disable();
c4a68306
AB
539 if (!irqs_disabled()) {
540 printk(KERN_WARNING "start_kernel(): bug: interrupts were "
541 "enabled *very* early, fixing it\n");
542 local_irq_disable();
543 }
9f58a205 544 idr_init_cache();
24a24bb6 545 perf_event_init();
1da177e4 546 rcu_init();
773e3eb7 547 radix_tree_init();
0b8f1efa
YL
548 /* init some links before init_ISA_irqs() */
549 early_irq_init();
1da177e4 550 init_IRQ();
3c7b4e6b 551 prio_tree_init();
1da177e4 552 init_timers();
c0a31329 553 hrtimers_init();
1da177e4 554 softirq_init();
ad596171 555 timekeeping_init();
88fecaa2 556 time_init();
93e02814 557 profile_init();
d8ad7d11 558 call_function_init();
93e02814 559 if (!irqs_disabled())
24d431d0
RL
560 printk(KERN_CRIT "start_kernel(): bug: interrupts were "
561 "enabled early\n");
2ce802f6 562 early_boot_irqs_disabled = false;
93e02814 563 local_irq_enable();
dcce284a 564
7e85ee0c 565 kmem_cache_init_late();
1da177e4
LT
566
567 /*
568 * HACK ALERT! This is early. We're enabling the console before
569 * we've done PCI setups etc, and console_init() must be aware of
570 * this. But we do want output early, in case something goes wrong.
571 */
572 console_init();
573 if (panic_later)
574 panic(panic_later, panic_param);
fbb9ce95
IM
575
576 lockdep_info();
577
9a11b49a
IM
578 /*
579 * Need to run this when irqs are enabled, because it wants
580 * to self-test [hard/soft]-irqs on/off lock inversion bugs
581 * too:
582 */
583 locking_selftest();
584
1da177e4
LT
585#ifdef CONFIG_BLK_DEV_INITRD
586 if (initrd_start && !initrd_below_start_ok &&
bd673c7c 587 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
1da177e4 588 printk(KERN_CRIT "initrd overwritten (0x%08lx < 0x%08lx) - "
fb6624eb 589 "disabling it.\n",
bd673c7c
GU
590 page_to_pfn(virt_to_page((void *)initrd_start)),
591 min_low_pfn);
1da177e4
LT
592 initrd_start = 0;
593 }
594#endif
94b6da5a 595 page_cgroup_init();
3ac7fe5a 596 debug_objects_mem_init();
9b090f2d 597 kmemleak_init();
e7c8d5c9 598 setup_per_cpu_pageset();
1da177e4
LT
599 numa_policy_init();
600 if (late_time_init)
601 late_time_init();
fa84e9ee 602 sched_clock_init();
1da177e4
LT
603 calibrate_delay();
604 pidmap_init();
1da177e4 605 anon_vma_init();
f026cfa8
PA
606#ifdef CONFIG_X86
607 if (efi_enabled)
608 efi_enter_virtual_mode();
609#endif
8c9843e5 610 thread_info_cache_init();
d84f4f99 611 cred_init();
4481374c 612 fork_init(totalram_pages);
1da177e4
LT
613 proc_caches_init();
614 buffer_init();
1da177e4
LT
615 key_init();
616 security_init();
0b4b3827 617 dbg_late_init();
4481374c 618 vfs_caches_init(totalram_pages);
1da177e4
LT
619 signals_init();
620 /* rootfs populating might need page-writeback */
621 page_writeback_init();
622#ifdef CONFIG_PROC_FS
623 proc_root_init();
624#endif
ddbcc7e8 625 cgroup_init();
1da177e4 626 cpuset_init();
c757249a 627 taskstats_init_early();
ca74e92b 628 delayacct_init();
1da177e4
LT
629
630 check_bugs();
631
632 acpi_early_init(); /* before LAPIC and SMP init */
6ae6996a 633 sfi_init_late();
1da177e4 634
68bf21aa
SR
635 ftrace_init();
636
1da177e4
LT
637 /* Do the rest non-__init'ed, we're now alive */
638 rest_init();
639}
640
b99b87f7
PO
641/* Call all constructor functions linked into the kernel. */
642static void __init do_ctors(void)
643{
644#ifdef CONFIG_CONSTRUCTORS
196a15b4 645 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start;
b99b87f7 646
196a15b4
HS
647 for (; fn < (ctor_fn_t *) __ctors_end; fn++)
648 (*fn)();
b99b87f7
PO
649#endif
650}
651
2329abfa 652bool initcall_debug;
d0ea3d7d 653core_param(initcall_debug, initcall_debug, bool, 0644);
1da177e4 654
4a683bf9 655static char msgbuf[64];
4a683bf9 656
e4461271 657static int __init_or_module do_one_initcall_debug(initcall_t fn)
1da177e4 658{
74239072 659 ktime_t calltime, delta, rettime;
30dbb20e
AW
660 unsigned long long duration;
661 int ret;
1da177e4 662
22c5c03b
KW
663 printk(KERN_DEBUG "calling %pF @ %i\n", fn, task_pid_nr(current));
664 calltime = ktime_get();
30dbb20e 665 ret = fn();
22c5c03b
KW
666 rettime = ktime_get();
667 delta = ktime_sub(rettime, calltime);
668 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
669 printk(KERN_DEBUG "initcall %pF returned %d after %lld usecs\n", fn,
670 ret, duration);
1da177e4 671
22c5c03b
KW
672 return ret;
673}
674
e4461271 675int __init_or_module do_one_initcall(initcall_t fn)
22c5c03b
KW
676{
677 int count = preempt_count();
678 int ret;
679
680 if (initcall_debug)
681 ret = do_one_initcall_debug(fn);
682 else
683 ret = fn();
8f0c45cd 684
e0df154f 685 msgbuf[0] = 0;
e662e1cf 686
30dbb20e
AW
687 if (ret && ret != -ENODEV && initcall_debug)
688 sprintf(msgbuf, "error code %d ", ret);
e662e1cf 689
e0df154f 690 if (preempt_count() != count) {
a76bfd0d 691 strlcat(msgbuf, "preemption imbalance ", sizeof(msgbuf));
e0df154f 692 preempt_count() = count;
1da177e4 693 }
e0df154f 694 if (irqs_disabled()) {
a76bfd0d 695 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf));
e0df154f
LT
696 local_irq_enable();
697 }
698 if (msgbuf[0]) {
96d746c6 699 printk("initcall %pF returned with %s\n", fn, msgbuf);
e0df154f 700 }
59f9415f 701
30dbb20e 702 return ret;
e0df154f
LT
703}
704
705
026cee00
PM
706extern initcall_t __initcall_start[];
707extern initcall_t __initcall0_start[];
708extern initcall_t __initcall1_start[];
709extern initcall_t __initcall2_start[];
710extern initcall_t __initcall3_start[];
711extern initcall_t __initcall4_start[];
712extern initcall_t __initcall5_start[];
713extern initcall_t __initcall6_start[];
714extern initcall_t __initcall7_start[];
715extern initcall_t __initcall_end[];
716
717static initcall_t *initcall_levels[] __initdata = {
718 __initcall0_start,
719 __initcall1_start,
720 __initcall2_start,
721 __initcall3_start,
722 __initcall4_start,
723 __initcall5_start,
724 __initcall6_start,
725 __initcall7_start,
726 __initcall_end,
727};
728
96263d28 729/* Keep these in sync with initcalls in include/linux/init.h */
026cee00 730static char *initcall_level_names[] __initdata = {
9fb48c74
JC
731 "early",
732 "core",
733 "postcore",
734 "arch",
735 "subsys",
736 "fs",
737 "device",
738 "late",
026cee00
PM
739};
740
026cee00 741static void __init do_initcall_level(int level)
e0df154f 742{
026cee00 743 extern const struct kernel_param __start___param[], __stop___param[];
196a15b4 744 initcall_t *fn;
e0df154f 745
026cee00
PM
746 strcpy(static_command_line, saved_command_line);
747 parse_args(initcall_level_names[level],
748 static_command_line, __start___param,
749 __stop___param - __start___param,
750 level, level,
eb157427 751 &repair_env_string);
026cee00
PM
752
753 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++)
196a15b4 754 do_one_initcall(*fn);
1da177e4
LT
755}
756
026cee00
PM
757static void __init do_initcalls(void)
758{
759 int level;
760
19efb72f 761 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++)
026cee00
PM
762 do_initcall_level(level);
763}
764
1da177e4
LT
765/*
766 * Ok, the machine is now initialized. None of the devices
767 * have been touched yet, but the CPU subsystem is up and
768 * running, and memory and process management works.
769 *
770 * Now we can finally start doing some real work..
771 */
772static void __init do_basic_setup(void)
773{
759ee091 774 cpuset_init_smp();
1da177e4 775 usermodehelper_init();
41ffe5d5 776 shmem_init();
1da177e4 777 driver_init();
b04c3afb 778 init_irq_proc();
b99b87f7 779 do_ctors();
d5767c53 780 usermodehelper_enable();
b0f84374 781 do_initcalls();
1da177e4
LT
782}
783
7babe8db 784static void __init do_pre_smp_initcalls(void)
c2147a50 785{
196a15b4 786 initcall_t *fn;
c2147a50 787
026cee00 788 for (fn = __initcall_start; fn < __initcall0_start; fn++)
196a15b4 789 do_one_initcall(*fn);
c2147a50
EGM
790}
791
a74fb73c 792static int run_init_process(const char *init_filename)
1da177e4
LT
793{
794 argv_init[0] = init_filename;
a74fb73c 795 return kernel_execve(init_filename, argv_init, envp_init);
1da177e4
LT
796}
797
d6b21238
AV
798static void __init kernel_init_freeable(void);
799
800static int __ref kernel_init(void *unused)
ee5bfa64 801{
d6b21238 802 kernel_init_freeable();
22a9d645
AV
803 /* need to finish all async __init code before freeing the memory */
804 async_synchronize_full();
ee5bfa64 805 free_initmem();
ee5bfa64
VG
806 mark_rodata_ro();
807 system_state = SYSTEM_RUNNING;
808 numa_default_policy();
809
fae5fa44 810 current->signal->flags |= SIGNAL_UNKILLABLE;
4a9d4b02 811 flush_delayed_fput();
fae5fa44 812
ee5bfa64 813 if (ramdisk_execute_command) {
a74fb73c
AV
814 if (!run_init_process(ramdisk_execute_command))
815 return 0;
ee5bfa64
VG
816 printk(KERN_WARNING "Failed to execute %s\n",
817 ramdisk_execute_command);
818 }
819
820 /*
821 * We try each of these until one succeeds.
822 *
823 * The Bourne shell can be used instead of init if we are
824 * trying to recover a really broken machine.
825 */
826 if (execute_command) {
a74fb73c
AV
827 if (!run_init_process(execute_command))
828 return 0;
ee5bfa64
VG
829 printk(KERN_WARNING "Failed to execute %s. Attempting "
830 "defaults...\n", execute_command);
831 }
a74fb73c
AV
832 if (!run_init_process("/sbin/init") ||
833 !run_init_process("/etc/init") ||
834 !run_init_process("/bin/init") ||
835 !run_init_process("/bin/sh"))
836 return 0;
ee5bfa64 837
9a85b8d6
AM
838 panic("No init found. Try passing init= option to kernel. "
839 "See Linux Documentation/init.txt for guidance.");
ee5bfa64
VG
840}
841
d6b21238 842static void __init kernel_init_freeable(void)
1da177e4 843{
b433c3d4
PZ
844 /*
845 * Wait until kthreadd is all set-up.
846 */
847 wait_for_completion(&kthreadd_done);
31a67102
LT
848
849 /* Now the scheduler is fully set up and can do blocking allocations */
850 gfp_allowed_mask = __GFP_BITS_MASK;
851
58568d2a
MX
852 /*
853 * init can allocate pages on any node
854 */
5ab116c9 855 set_mems_allowed(node_states[N_HIGH_MEMORY]);
1da177e4
LT
856 /*
857 * init can run on any cpu.
858 */
1a2142af 859 set_cpus_allowed_ptr(current, cpu_all_mask);
1da177e4 860
9ec52099
CLG
861 cad_pid = task_pid(current);
862
ca74a6f8 863 smp_prepare_cpus(setup_max_cpus);
1da177e4
LT
864
865 do_pre_smp_initcalls();
004417a6 866 lockup_detector_init();
1da177e4 867
1da177e4
LT
868 smp_init();
869 sched_init_smp();
870
1da177e4
LT
871 do_basic_setup();
872
2bd3a997
EB
873 /* Open the /dev/console on the rootfs, this should never fail */
874 if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
875 printk(KERN_WARNING "Warning: unable to open an initial console.\n");
876
877 (void) sys_dup(0);
878 (void) sys_dup(0);
1da177e4
LT
879 /*
880 * check if there is an early userspace init. If yes, let it do all
881 * the work
882 */
ffdfc409
OJ
883
884 if (!ramdisk_execute_command)
885 ramdisk_execute_command = "/init";
886
887 if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
888 ramdisk_execute_command = NULL;
1da177e4 889 prepare_namespace();
ffdfc409 890 }
1da177e4
LT
891
892 /*
893 * Ok, we have completed the initial bootup, and
894 * we're essentially up and running. Get rid of the
895 * initmem segments and start the user-mode stuff..
896 */
1da177e4 897}
This page took 0.815815 seconds and 5 git commands to generate.