]> git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blame - init/main.c
module_param: stop double-calling parameters.
[mirror_ubuntu-zesty-kernel.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>
1da177e4
LT
71
72#include <asm/io.h>
73#include <asm/bugs.h>
74#include <asm/setup.h>
a940199f 75#include <asm/sections.h>
37b73c82 76#include <asm/cacheflush.h>
1da177e4 77
1da177e4
LT
78#ifdef CONFIG_X86_LOCAL_APIC
79#include <asm/smp.h>
80#endif
81
aae5f662 82static int kernel_init(void *);
1da177e4
LT
83
84extern void init_IRQ(void);
1da177e4
LT
85extern void fork_init(unsigned long);
86extern void mca_init(void);
87extern void sbus_init(void);
1da177e4
LT
88extern void prio_tree_init(void);
89extern void radix_tree_init(void);
37b73c82
AV
90#ifndef CONFIG_DEBUG_RODATA
91static inline void mark_rodata_ro(void) { }
92#endif
1da177e4
LT
93
94#ifdef CONFIG_TC
95extern void tc_init(void);
96#endif
97
2ce802f6
TH
98/*
99 * Debug helper: via this flag we know that we are in 'early bootup code'
100 * where only the boot processor is running with IRQ disabled. This means
101 * two things - IRQ must not be enabled before the flag is cleared and some
102 * operations which are not allowed with IRQ disabled are allowed while the
103 * flag is set.
104 */
105bool early_boot_irqs_disabled __read_mostly;
106
a6826048 107enum system_states system_state __read_mostly;
1da177e4
LT
108EXPORT_SYMBOL(system_state);
109
110/*
111 * Boot command-line arguments
112 */
113#define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
114#define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
115
116extern void time_init(void);
117/* Default late time init is NULL. archs can override this later. */
d2e3192b 118void (*__initdata late_time_init)(void);
1da177e4
LT
119extern void softirq_init(void);
120
30d7e0d4
ABL
121/* Untouched command line saved by arch-specific code. */
122char __initdata boot_command_line[COMMAND_LINE_SIZE];
123/* Untouched saved command line (eg. for /proc) */
124char *saved_command_line;
125/* Command line for parameter parsing */
126static char *static_command_line;
1da177e4
LT
127
128static char *execute_command;
ffdfc409 129static char *ramdisk_execute_command;
1da177e4 130
8b3b2955
JB
131/*
132 * If set, this is an indication to the drivers that reset the underlying
133 * device before going ahead with the initialization otherwise driver might
134 * rely on the BIOS and skip the reset operation.
135 *
136 * This is useful if kernel is booting in an unreliable environment.
137 * For ex. kdump situaiton where previous kernel has crashed, BIOS has been
138 * skipped and devices will be in unknown state.
139 */
140unsigned int reset_devices;
141EXPORT_SYMBOL(reset_devices);
1da177e4 142
7e96287d
VG
143static int __init set_reset_devices(char *str)
144{
145 reset_devices = 1;
146 return 1;
147}
148
149__setup("reset_devices", set_reset_devices);
150
d7627467
DH
151static const char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
152const char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
1da177e4
LT
153static const char *panic_later, *panic_param;
154
914dcaa8 155extern const struct obs_kernel_param __setup_start[], __setup_end[];
1da177e4
LT
156
157static int __init obsolete_checksetup(char *line)
158{
914dcaa8 159 const struct obs_kernel_param *p;
33df0d19 160 int had_early_param = 0;
1da177e4
LT
161
162 p = __setup_start;
163 do {
164 int n = strlen(p->str);
b1e4d20c 165 if (parameqn(line, p->str, n)) {
1da177e4 166 if (p->early) {
33df0d19
RR
167 /* Already done in parse_early_param?
168 * (Needs exact match on param part).
169 * Keep iterating, as we can have early
170 * params and __setups of same names 8( */
1da177e4 171 if (line[n] == '\0' || line[n] == '=')
33df0d19 172 had_early_param = 1;
1da177e4
LT
173 } else if (!p->setup_func) {
174 printk(KERN_WARNING "Parameter %s is obsolete,"
175 " ignored\n", p->str);
176 return 1;
177 } else if (p->setup_func(line + n))
178 return 1;
179 }
180 p++;
181 } while (p < __setup_end);
33df0d19
RR
182
183 return had_early_param;
1da177e4
LT
184}
185
186/*
187 * This should be approx 2 Bo*oMips to start (note initial shift), and will
188 * still work even if initially too large, it will just take slightly longer
189 */
190unsigned long loops_per_jiffy = (1<<12);
191
192EXPORT_SYMBOL(loops_per_jiffy);
193
194static int __init debug_kernel(char *str)
195{
1da177e4 196 console_loglevel = 10;
f6f21c81 197 return 0;
1da177e4
LT
198}
199
200static int __init quiet_kernel(char *str)
201{
1da177e4 202 console_loglevel = 4;
f6f21c81 203 return 0;
1da177e4
LT
204}
205
f6f21c81
YL
206early_param("debug", debug_kernel);
207early_param("quiet", quiet_kernel);
1da177e4
LT
208
209static int __init loglevel(char *str)
210{
808bf29b
AS
211 int newlevel;
212
213 /*
214 * Only update loglevel value when a correct setting was passed,
215 * to prevent blind crashes (when loglevel being set to 0) that
216 * are quite hard to debug
217 */
218 if (get_option(&str, &newlevel)) {
219 console_loglevel = newlevel;
220 return 0;
221 }
222
223 return -EINVAL;
1da177e4
LT
224}
225
f6f21c81 226early_param("loglevel", loglevel);
1da177e4 227
a99cd112 228/* Change NUL term back to "=", to make "param" the whole string. */
eb157427 229static int __init repair_env_string(char *param, char *val, const char *unused)
1da177e4 230{
1da177e4
LT
231 if (val) {
232 /* param=val or param="val"? */
233 if (val == param+strlen(param)+1)
234 val[-1] = '=';
235 else if (val == param+strlen(param)+2) {
236 val[-2] = '=';
237 memmove(val-1, val, strlen(val)+1);
238 val--;
239 } else
240 BUG();
241 }
a99cd112
CM
242 return 0;
243}
244
245/*
246 * Unknown boot options get handed to init, unless they look like
247 * unused parameters (modprobe will find them in /proc/cmdline).
248 */
eb157427 249static int __init unknown_bootoption(char *param, char *val, const char *unused)
a99cd112 250{
eb157427 251 repair_env_string(param, val, unused);
1da177e4
LT
252
253 /* Handle obsolete-style parameters */
254 if (obsolete_checksetup(param))
255 return 0;
256
f066a4f6
RR
257 /* Unused module parameter. */
258 if (strchr(param, '.') && (!val || strchr(param, '.') < val))
1da177e4 259 return 0;
1da177e4
LT
260
261 if (panic_later)
262 return 0;
263
264 if (val) {
265 /* Environment option */
266 unsigned int i;
267 for (i = 0; envp_init[i]; i++) {
268 if (i == MAX_INIT_ENVS) {
269 panic_later = "Too many boot env vars at `%s'";
270 panic_param = param;
271 }
272 if (!strncmp(param, envp_init[i], val - param))
273 break;
274 }
275 envp_init[i] = param;
276 } else {
277 /* Command line option */
278 unsigned int i;
279 for (i = 0; argv_init[i]; i++) {
280 if (i == MAX_INIT_ARGS) {
281 panic_later = "Too many boot init vars at `%s'";
282 panic_param = param;
283 }
284 }
285 argv_init[i] = param;
286 }
287 return 0;
288}
289
290static int __init init_setup(char *str)
291{
292 unsigned int i;
293
294 execute_command = str;
295 /*
296 * In case LILO is going to boot us with default command line,
297 * it prepends "auto" before the whole cmdline which makes
298 * the shell think it should execute a script with such name.
299 * So we ignore all arguments entered _before_ init=... [MJ]
300 */
301 for (i = 1; i < MAX_INIT_ARGS; i++)
302 argv_init[i] = NULL;
303 return 1;
304}
305__setup("init=", init_setup);
306
ffdfc409
OJ
307static int __init rdinit_setup(char *str)
308{
309 unsigned int i;
310
311 ramdisk_execute_command = str;
312 /* See "auto" comment in init_setup */
313 for (i = 1; i < MAX_INIT_ARGS; i++)
314 argv_init[i] = NULL;
315 return 1;
316}
317__setup("rdinit=", rdinit_setup);
318
1da177e4 319#ifndef CONFIG_SMP
34db18a0 320static const unsigned int setup_max_cpus = NR_CPUS;
1da177e4
LT
321#ifdef CONFIG_X86_LOCAL_APIC
322static void __init smp_init(void)
323{
324 APIC_init_uniprocessor();
325}
326#else
327#define smp_init() do { } while (0)
328#endif
329
e0982e90 330static inline void setup_nr_cpu_ids(void) { }
1da177e4 331static inline void smp_prepare_cpus(unsigned int maxcpus) { }
1da177e4
LT
332#endif
333
30d7e0d4
ABL
334/*
335 * We need to store the untouched command line for future reference.
336 * We also need to store the touched command line since the parameter
337 * parsing is performed in place, and we should allow a component to
338 * store reference of name/value for future reference.
339 */
340static void __init setup_command_line(char *command_line)
341{
342 saved_command_line = alloc_bootmem(strlen (boot_command_line)+1);
343 static_command_line = alloc_bootmem(strlen (command_line)+1);
344 strcpy (saved_command_line, boot_command_line);
345 strcpy (static_command_line, command_line);
346}
347
1da177e4
LT
348/*
349 * We need to finalize in a non-__init function or else race conditions
350 * between the root thread and the init thread may cause start_kernel to
351 * be reaped by free_initmem before the root thread has proceeded to
352 * cpu_idle.
353 *
354 * gcc-3.4 accidentally inlines this function, so use noinline.
355 */
356
b433c3d4
PZ
357static __initdata DECLARE_COMPLETION(kthreadd_done);
358
f99ebf0a 359static noinline void __init_refok rest_init(void)
1da177e4 360{
73c27992
EB
361 int pid;
362
7db905e6 363 rcu_scheduler_starting();
b433c3d4 364 /*
97158569 365 * We need to spawn init first so that it obtains pid 1, however
b433c3d4
PZ
366 * the init task will end up wanting to create kthreads, which, if
367 * we schedule it before we create kthreadd, will OOPS.
368 */
aae5f662 369 kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND);
1da177e4 370 numa_default_policy();
73c27992 371 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
d11c563d 372 rcu_read_lock();
5cd20455 373 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
d11c563d 374 rcu_read_unlock();
b433c3d4 375 complete(&kthreadd_done);
f340c0d1
IM
376
377 /*
378 * The boot idle thread must execute schedule()
1df21055 379 * at least once to get things moving:
f340c0d1 380 */
1df21055 381 init_idle_bootup_task(current);
bd2f5536 382 schedule_preempt_disabled();
5bfb5d69 383 /* Call into cpu_idle with preempt disabled */
1da177e4 384 cpu_idle();
1df21055 385}
1da177e4
LT
386
387/* Check for early params. */
9fb48c74 388static int __init do_early_param(char *param, char *val, const char *unused)
1da177e4 389{
914dcaa8 390 const struct obs_kernel_param *p;
1da177e4
LT
391
392 for (p = __setup_start; p < __setup_end; p++) {
b1e4d20c 393 if ((p->early && parameq(param, p->str)) ||
18a8bd94
YL
394 (strcmp(param, "console") == 0 &&
395 strcmp(p->str, "earlycon") == 0)
396 ) {
1da177e4
LT
397 if (p->setup_func(val) != 0)
398 printk(KERN_WARNING
399 "Malformed early option '%s'\n", param);
400 }
401 }
402 /* We accept everything at this stage. */
403 return 0;
404}
405
13977091
MD
406void __init parse_early_options(char *cmdline)
407{
026cee00 408 parse_args("early options", cmdline, NULL, 0, 0, 0, do_early_param);
13977091
MD
409}
410
1da177e4
LT
411/* Arch code calls this early on, or if not, just before other parsing. */
412void __init parse_early_param(void)
413{
414 static __initdata int done = 0;
415 static __initdata char tmp_cmdline[COMMAND_LINE_SIZE];
416
417 if (done)
418 return;
419
420 /* All fall through to do_early_param. */
30d7e0d4 421 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
13977091 422 parse_early_options(tmp_cmdline);
1da177e4
LT
423 done = 1;
424}
425
426/*
427 * Activate the first processor.
428 */
429
44fd2299
SS
430static void __init boot_cpu_init(void)
431{
432 int cpu = smp_processor_id();
433 /* Mark the boot cpu "present", "online" etc for SMP and UP case */
915441b6 434 set_cpu_online(cpu, true);
933b0618 435 set_cpu_active(cpu, true);
915441b6
RR
436 set_cpu_present(cpu, true);
437 set_cpu_possible(cpu, true);
44fd2299
SS
438}
439
839ad62e 440void __init __weak smp_setup_processor_id(void)
033ab7f8
AM
441{
442}
443
8c9843e5
BH
444void __init __weak thread_info_cache_init(void)
445{
446}
447
444f478f
PE
448/*
449 * Set up kernel memory allocators
450 */
451static void __init mm_init(void)
452{
ca371c0d 453 /*
7fa87ce7
JC
454 * page_cgroup requires contiguous pages,
455 * bigger than MAX_ORDER unless SPARSEMEM.
ca371c0d
KH
456 */
457 page_cgroup_init_flatmem();
444f478f
PE
458 mem_init();
459 kmem_cache_init();
099a19d9 460 percpu_init_late();
c868d550 461 pgtable_cache_init();
444f478f
PE
462 vmalloc_init();
463}
464
1da177e4
LT
465asmlinkage void __init start_kernel(void)
466{
467 char * command_line;
914dcaa8 468 extern const struct kernel_param __start___param[], __stop___param[];
033ab7f8 469
fbb9ce95
IM
470 /*
471 * Need to run as early as possible, to initialize the
472 * lockdep hash:
473 */
474 lockdep_init();
73839c5b 475 smp_setup_processor_id();
3ac7fe5a 476 debug_objects_early_init();
42059429
IM
477
478 /*
479 * Set up the the initial canary ASAP:
480 */
481 boot_init_stack_canary();
482
ddbcc7e8 483 cgroup_init_early();
fbb9ce95
IM
484
485 local_irq_disable();
2ce802f6 486 early_boot_irqs_disabled = true;
fbb9ce95 487
1da177e4
LT
488/*
489 * Interrupts are still disabled. Do necessary setups, then
490 * enable them
491 */
906568c9 492 tick_init();
44fd2299 493 boot_cpu_init();
1da177e4 494 page_address_init();
657cafa6 495 printk(KERN_NOTICE "%s", linux_banner);
1da177e4 496 setup_arch(&command_line);
cf475ad2 497 mm_init_owner(&init_mm, &init_task);
6345d24d 498 mm_init_cpumask(&init_mm);
30d7e0d4 499 setup_command_line(command_line);
e0982e90 500 setup_nr_cpu_ids();
d6647bdf 501 setup_per_cpu_areas();
44fd2299 502 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
1da177e4 503
1f522509 504 build_all_zonelists(NULL);
83b519e8
PE
505 page_alloc_init();
506
507 printk(KERN_NOTICE "Kernel command line: %s\n", boot_command_line);
508 parse_early_param();
509 parse_args("Booting kernel", static_command_line, __start___param,
510 __stop___param - __start___param,
ae82fdb1 511 -1, -1, &unknown_bootoption);
97ce2c88
JF
512
513 jump_label_init();
514
83b519e8
PE
515 /*
516 * These use large bootmem allocations and must precede
517 * kmem_cache_init()
518 */
162a7e75 519 setup_log_buf(0);
83b519e8 520 pidhash_init();
83b519e8
PE
521 vfs_caches_init_early();
522 sort_main_extable();
523 trap_init();
444f478f 524 mm_init();
de03c72c 525
1da177e4
LT
526 /*
527 * Set up the scheduler prior starting any interrupts (such as the
528 * timer interrupt). Full topology setup happens at smp_init()
529 * time - but meanwhile we still have a functioning scheduler.
530 */
531 sched_init();
532 /*
533 * Disable preemption - early bootup scheduling is extremely
534 * fragile until we cpu_idle() for the first time.
535 */
536 preempt_disable();
c4a68306
AB
537 if (!irqs_disabled()) {
538 printk(KERN_WARNING "start_kernel(): bug: interrupts were "
539 "enabled *very* early, fixing it\n");
540 local_irq_disable();
541 }
9f58a205 542 idr_init_cache();
24a24bb6 543 perf_event_init();
1da177e4 544 rcu_init();
773e3eb7 545 radix_tree_init();
0b8f1efa
YL
546 /* init some links before init_ISA_irqs() */
547 early_irq_init();
1da177e4 548 init_IRQ();
3c7b4e6b 549 prio_tree_init();
1da177e4 550 init_timers();
c0a31329 551 hrtimers_init();
1da177e4 552 softirq_init();
ad596171 553 timekeeping_init();
88fecaa2 554 time_init();
93e02814 555 profile_init();
d8ad7d11 556 call_function_init();
93e02814 557 if (!irqs_disabled())
24d431d0
RL
558 printk(KERN_CRIT "start_kernel(): bug: interrupts were "
559 "enabled early\n");
2ce802f6 560 early_boot_irqs_disabled = false;
93e02814 561 local_irq_enable();
dcce284a 562
7e85ee0c 563 kmem_cache_init_late();
1da177e4
LT
564
565 /*
566 * HACK ALERT! This is early. We're enabling the console before
567 * we've done PCI setups etc, and console_init() must be aware of
568 * this. But we do want output early, in case something goes wrong.
569 */
570 console_init();
571 if (panic_later)
572 panic(panic_later, panic_param);
fbb9ce95
IM
573
574 lockdep_info();
575
9a11b49a
IM
576 /*
577 * Need to run this when irqs are enabled, because it wants
578 * to self-test [hard/soft]-irqs on/off lock inversion bugs
579 * too:
580 */
581 locking_selftest();
582
1da177e4
LT
583#ifdef CONFIG_BLK_DEV_INITRD
584 if (initrd_start && !initrd_below_start_ok &&
bd673c7c 585 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
1da177e4 586 printk(KERN_CRIT "initrd overwritten (0x%08lx < 0x%08lx) - "
fb6624eb 587 "disabling it.\n",
bd673c7c
GU
588 page_to_pfn(virt_to_page((void *)initrd_start)),
589 min_low_pfn);
1da177e4
LT
590 initrd_start = 0;
591 }
592#endif
94b6da5a 593 page_cgroup_init();
3ac7fe5a 594 debug_objects_mem_init();
9b090f2d 595 kmemleak_init();
e7c8d5c9 596 setup_per_cpu_pageset();
1da177e4
LT
597 numa_policy_init();
598 if (late_time_init)
599 late_time_init();
fa84e9ee 600 sched_clock_init();
1da177e4
LT
601 calibrate_delay();
602 pidmap_init();
1da177e4
LT
603 anon_vma_init();
604#ifdef CONFIG_X86
605 if (efi_enabled)
606 efi_enter_virtual_mode();
607#endif
8c9843e5 608 thread_info_cache_init();
d84f4f99 609 cred_init();
4481374c 610 fork_init(totalram_pages);
1da177e4
LT
611 proc_caches_init();
612 buffer_init();
1da177e4
LT
613 key_init();
614 security_init();
0b4b3827 615 dbg_late_init();
4481374c 616 vfs_caches_init(totalram_pages);
1da177e4
LT
617 signals_init();
618 /* rootfs populating might need page-writeback */
619 page_writeback_init();
620#ifdef CONFIG_PROC_FS
621 proc_root_init();
622#endif
ddbcc7e8 623 cgroup_init();
1da177e4 624 cpuset_init();
c757249a 625 taskstats_init_early();
ca74e92b 626 delayacct_init();
1da177e4
LT
627
628 check_bugs();
629
630 acpi_early_init(); /* before LAPIC and SMP init */
6ae6996a 631 sfi_init_late();
1da177e4 632
68bf21aa
SR
633 ftrace_init();
634
1da177e4
LT
635 /* Do the rest non-__init'ed, we're now alive */
636 rest_init();
637}
638
b99b87f7
PO
639/* Call all constructor functions linked into the kernel. */
640static void __init do_ctors(void)
641{
642#ifdef CONFIG_CONSTRUCTORS
196a15b4 643 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start;
b99b87f7 644
196a15b4
HS
645 for (; fn < (ctor_fn_t *) __ctors_end; fn++)
646 (*fn)();
b99b87f7
PO
647#endif
648}
649
2329abfa 650bool initcall_debug;
d0ea3d7d 651core_param(initcall_debug, initcall_debug, bool, 0644);
1da177e4 652
4a683bf9 653static char msgbuf[64];
4a683bf9 654
e4461271 655static int __init_or_module do_one_initcall_debug(initcall_t fn)
1da177e4 656{
74239072 657 ktime_t calltime, delta, rettime;
30dbb20e
AW
658 unsigned long long duration;
659 int ret;
1da177e4 660
22c5c03b
KW
661 printk(KERN_DEBUG "calling %pF @ %i\n", fn, task_pid_nr(current));
662 calltime = ktime_get();
30dbb20e 663 ret = fn();
22c5c03b
KW
664 rettime = ktime_get();
665 delta = ktime_sub(rettime, calltime);
666 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
667 printk(KERN_DEBUG "initcall %pF returned %d after %lld usecs\n", fn,
668 ret, duration);
1da177e4 669
22c5c03b
KW
670 return ret;
671}
672
e4461271 673int __init_or_module do_one_initcall(initcall_t fn)
22c5c03b
KW
674{
675 int count = preempt_count();
676 int ret;
677
678 if (initcall_debug)
679 ret = do_one_initcall_debug(fn);
680 else
681 ret = fn();
8f0c45cd 682
e0df154f 683 msgbuf[0] = 0;
e662e1cf 684
30dbb20e
AW
685 if (ret && ret != -ENODEV && initcall_debug)
686 sprintf(msgbuf, "error code %d ", ret);
e662e1cf 687
e0df154f 688 if (preempt_count() != count) {
a76bfd0d 689 strlcat(msgbuf, "preemption imbalance ", sizeof(msgbuf));
e0df154f 690 preempt_count() = count;
1da177e4 691 }
e0df154f 692 if (irqs_disabled()) {
a76bfd0d 693 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf));
e0df154f
LT
694 local_irq_enable();
695 }
696 if (msgbuf[0]) {
96d746c6 697 printk("initcall %pF returned with %s\n", fn, msgbuf);
e0df154f 698 }
59f9415f 699
30dbb20e 700 return ret;
e0df154f
LT
701}
702
703
026cee00
PM
704extern initcall_t __initcall_start[];
705extern initcall_t __initcall0_start[];
706extern initcall_t __initcall1_start[];
707extern initcall_t __initcall2_start[];
708extern initcall_t __initcall3_start[];
709extern initcall_t __initcall4_start[];
710extern initcall_t __initcall5_start[];
711extern initcall_t __initcall6_start[];
712extern initcall_t __initcall7_start[];
713extern initcall_t __initcall_end[];
714
715static initcall_t *initcall_levels[] __initdata = {
716 __initcall0_start,
717 __initcall1_start,
718 __initcall2_start,
719 __initcall3_start,
720 __initcall4_start,
721 __initcall5_start,
722 __initcall6_start,
723 __initcall7_start,
724 __initcall_end,
725};
726
727static char *initcall_level_names[] __initdata = {
9fb48c74
JC
728 "early",
729 "core",
730 "postcore",
731 "arch",
732 "subsys",
733 "fs",
734 "device",
735 "late",
026cee00
PM
736};
737
026cee00 738static void __init do_initcall_level(int level)
e0df154f 739{
026cee00 740 extern const struct kernel_param __start___param[], __stop___param[];
196a15b4 741 initcall_t *fn;
e0df154f 742
026cee00
PM
743 strcpy(static_command_line, saved_command_line);
744 parse_args(initcall_level_names[level],
745 static_command_line, __start___param,
746 __stop___param - __start___param,
747 level, level,
eb157427 748 &repair_env_string);
026cee00
PM
749
750 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++)
196a15b4 751 do_one_initcall(*fn);
1da177e4
LT
752}
753
026cee00
PM
754static void __init do_initcalls(void)
755{
756 int level;
757
9fb48c74
JC
758 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) {
759 pr_info("initlevel:%d=%s, %d registered initcalls\n",
760 level, initcall_level_names[level],
761 (int) (initcall_levels[level+1]
762 - initcall_levels[level]));
026cee00 763 do_initcall_level(level);
9fb48c74 764 }
026cee00
PM
765}
766
1da177e4
LT
767/*
768 * Ok, the machine is now initialized. None of the devices
769 * have been touched yet, but the CPU subsystem is up and
770 * running, and memory and process management works.
771 *
772 * Now we can finally start doing some real work..
773 */
774static void __init do_basic_setup(void)
775{
759ee091 776 cpuset_init_smp();
1da177e4 777 usermodehelper_init();
41ffe5d5 778 shmem_init();
1da177e4 779 driver_init();
b04c3afb 780 init_irq_proc();
b99b87f7 781 do_ctors();
d5767c53 782 usermodehelper_enable();
b0f84374 783 do_initcalls();
1da177e4
LT
784}
785
7babe8db 786static void __init do_pre_smp_initcalls(void)
c2147a50 787{
196a15b4 788 initcall_t *fn;
c2147a50 789
026cee00 790 for (fn = __initcall_start; fn < __initcall0_start; fn++)
196a15b4 791 do_one_initcall(*fn);
c2147a50
EGM
792}
793
d7627467 794static void run_init_process(const char *init_filename)
1da177e4
LT
795{
796 argv_init[0] = init_filename;
67608567 797 kernel_execve(init_filename, argv_init, envp_init);
1da177e4
LT
798}
799
ee5bfa64
VG
800/* This is a non __init function. Force it to be noinline otherwise gcc
801 * makes it inline to init() and it becomes part of init.text section
802 */
f99ebf0a 803static noinline int init_post(void)
ee5bfa64 804{
22a9d645
AV
805 /* need to finish all async __init code before freeing the memory */
806 async_synchronize_full();
ee5bfa64 807 free_initmem();
ee5bfa64
VG
808 mark_rodata_ro();
809 system_state = SYSTEM_RUNNING;
810 numa_default_policy();
811
ee5bfa64 812
fae5fa44
ON
813 current->signal->flags |= SIGNAL_UNKILLABLE;
814
ee5bfa64
VG
815 if (ramdisk_execute_command) {
816 run_init_process(ramdisk_execute_command);
817 printk(KERN_WARNING "Failed to execute %s\n",
818 ramdisk_execute_command);
819 }
820
821 /*
822 * We try each of these until one succeeds.
823 *
824 * The Bourne shell can be used instead of init if we are
825 * trying to recover a really broken machine.
826 */
827 if (execute_command) {
828 run_init_process(execute_command);
829 printk(KERN_WARNING "Failed to execute %s. Attempting "
830 "defaults...\n", execute_command);
831 }
832 run_init_process("/sbin/init");
833 run_init_process("/etc/init");
834 run_init_process("/bin/init");
835 run_init_process("/bin/sh");
836
9a85b8d6
AM
837 panic("No init found. Try passing init= option to kernel. "
838 "See Linux Documentation/init.txt for guidance.");
ee5bfa64
VG
839}
840
aae5f662 841static int __init kernel_init(void * unused)
1da177e4 842{
b433c3d4
PZ
843 /*
844 * Wait until kthreadd is all set-up.
845 */
846 wait_for_completion(&kthreadd_done);
31a67102
LT
847
848 /* Now the scheduler is fully set up and can do blocking allocations */
849 gfp_allowed_mask = __GFP_BITS_MASK;
850
58568d2a
MX
851 /*
852 * init can allocate pages on any node
853 */
5ab116c9 854 set_mems_allowed(node_states[N_HIGH_MEMORY]);
1da177e4
LT
855 /*
856 * init can run on any cpu.
857 */
1a2142af 858 set_cpus_allowed_ptr(current, cpu_all_mask);
1da177e4 859
9ec52099
CLG
860 cad_pid = task_pid(current);
861
ca74a6f8 862 smp_prepare_cpus(setup_max_cpus);
1da177e4
LT
863
864 do_pre_smp_initcalls();
004417a6 865 lockup_detector_init();
1da177e4 866
1da177e4
LT
867 smp_init();
868 sched_init_smp();
869
1da177e4
LT
870 do_basic_setup();
871
2bd3a997
EB
872 /* Open the /dev/console on the rootfs, this should never fail */
873 if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
874 printk(KERN_WARNING "Warning: unable to open an initial console.\n");
875
876 (void) sys_dup(0);
877 (void) sys_dup(0);
1da177e4
LT
878 /*
879 * check if there is an early userspace init. If yes, let it do all
880 * the work
881 */
ffdfc409
OJ
882
883 if (!ramdisk_execute_command)
884 ramdisk_execute_command = "/init";
885
886 if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
887 ramdisk_execute_command = NULL;
1da177e4 888 prepare_namespace();
ffdfc409 889 }
1da177e4
LT
890
891 /*
892 * Ok, we have completed the initial bootup, and
893 * we're essentially up and running. Get rid of the
894 * initmem segments and start the user-mode stuff..
895 */
71566a0d 896
ee5bfa64
VG
897 init_post();
898 return 0;
1da177e4 899}