gru: fix automatic retry of gru instruction failures
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / init / main.c
blob1a65fdd06318f05c81e68d89fe7b80a3a1fcbbc5
1 /*
2 * linux/init/main.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
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>
12 #include <linux/types.h>
13 #include <linux/module.h>
14 #include <linux/proc_fs.h>
15 #include <linux/kernel.h>
16 #include <linux/syscalls.h>
17 #include <linux/stackprotector.h>
18 #include <linux/string.h>
19 #include <linux/ctype.h>
20 #include <linux/delay.h>
21 #include <linux/utsname.h>
22 #include <linux/ioport.h>
23 #include <linux/init.h>
24 #include <linux/smp_lock.h>
25 #include <linux/initrd.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/vmalloc.h>
32 #include <linux/kernel_stat.h>
33 #include <linux/start_kernel.h>
34 #include <linux/security.h>
35 #include <linux/smp.h>
36 #include <linux/workqueue.h>
37 #include <linux/profile.h>
38 #include <linux/rcupdate.h>
39 #include <linux/moduleparam.h>
40 #include <linux/kallsyms.h>
41 #include <linux/writeback.h>
42 #include <linux/cpu.h>
43 #include <linux/cpuset.h>
44 #include <linux/cgroup.h>
45 #include <linux/efi.h>
46 #include <linux/tick.h>
47 #include <linux/interrupt.h>
48 #include <linux/taskstats_kern.h>
49 #include <linux/delayacct.h>
50 #include <linux/unistd.h>
51 #include <linux/rmap.h>
52 #include <linux/mempolicy.h>
53 #include <linux/key.h>
54 #include <linux/buffer_head.h>
55 #include <linux/page_cgroup.h>
56 #include <linux/debug_locks.h>
57 #include <linux/debugobjects.h>
58 #include <linux/lockdep.h>
59 #include <linux/kmemleak.h>
60 #include <linux/pid_namespace.h>
61 #include <linux/device.h>
62 #include <linux/kthread.h>
63 #include <linux/sched.h>
64 #include <linux/signal.h>
65 #include <linux/idr.h>
66 #include <linux/ftrace.h>
67 #include <linux/async.h>
68 #include <linux/kmemcheck.h>
69 #include <linux/kmemtrace.h>
70 #include <trace/boot.h>
72 #include <asm/io.h>
73 #include <asm/bugs.h>
74 #include <asm/setup.h>
75 #include <asm/sections.h>
76 #include <asm/cacheflush.h>
78 #ifdef CONFIG_X86_LOCAL_APIC
79 #include <asm/smp.h>
80 #endif
82 static int kernel_init(void *);
84 extern void init_IRQ(void);
85 extern void fork_init(unsigned long);
86 extern void mca_init(void);
87 extern void sbus_init(void);
88 extern void prio_tree_init(void);
89 extern void radix_tree_init(void);
90 extern void free_initmem(void);
91 #ifdef CONFIG_ACPI
92 extern void acpi_early_init(void);
93 #else
94 static inline void acpi_early_init(void) { }
95 #endif
96 #ifndef CONFIG_DEBUG_RODATA
97 static inline void mark_rodata_ro(void) { }
98 #endif
100 #ifdef CONFIG_TC
101 extern void tc_init(void);
102 #endif
104 enum system_states system_state __read_mostly;
105 EXPORT_SYMBOL(system_state);
108 * Boot command-line arguments
110 #define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
111 #define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
113 extern void time_init(void);
114 /* Default late time init is NULL. archs can override this later. */
115 void (*__initdata late_time_init)(void);
116 extern void softirq_init(void);
118 /* Untouched command line saved by arch-specific code. */
119 char __initdata boot_command_line[COMMAND_LINE_SIZE];
120 /* Untouched saved command line (eg. for /proc) */
121 char *saved_command_line;
122 /* Command line for parameter parsing */
123 static char *static_command_line;
125 static char *execute_command;
126 static char *ramdisk_execute_command;
128 #ifdef CONFIG_SMP
129 /* Setup configured maximum number of CPUs to activate */
130 unsigned int __initdata setup_max_cpus = NR_CPUS;
133 * Setup routine for controlling SMP activation
135 * Command-line option of "nosmp" or "maxcpus=0" will disable SMP
136 * activation entirely (the MPS table probe still happens, though).
138 * Command-line option of "maxcpus=<NUM>", where <NUM> is an integer
139 * greater than 0, limits the maximum number of CPUs activated in
140 * SMP mode to <NUM>.
143 void __weak arch_disable_smp_support(void) { }
145 static int __init nosmp(char *str)
147 setup_max_cpus = 0;
148 arch_disable_smp_support();
150 return 0;
153 early_param("nosmp", nosmp);
155 static int __init maxcpus(char *str)
157 get_option(&str, &setup_max_cpus);
158 if (setup_max_cpus == 0)
159 arch_disable_smp_support();
161 return 0;
164 early_param("maxcpus", maxcpus);
165 #else
166 const unsigned int setup_max_cpus = NR_CPUS;
167 #endif
170 * If set, this is an indication to the drivers that reset the underlying
171 * device before going ahead with the initialization otherwise driver might
172 * rely on the BIOS and skip the reset operation.
174 * This is useful if kernel is booting in an unreliable environment.
175 * For ex. kdump situaiton where previous kernel has crashed, BIOS has been
176 * skipped and devices will be in unknown state.
178 unsigned int reset_devices;
179 EXPORT_SYMBOL(reset_devices);
181 static int __init set_reset_devices(char *str)
183 reset_devices = 1;
184 return 1;
187 __setup("reset_devices", set_reset_devices);
189 static char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
190 char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
191 static const char *panic_later, *panic_param;
193 extern struct obs_kernel_param __setup_start[], __setup_end[];
195 static int __init obsolete_checksetup(char *line)
197 struct obs_kernel_param *p;
198 int had_early_param = 0;
200 p = __setup_start;
201 do {
202 int n = strlen(p->str);
203 if (!strncmp(line, p->str, n)) {
204 if (p->early) {
205 /* Already done in parse_early_param?
206 * (Needs exact match on param part).
207 * Keep iterating, as we can have early
208 * params and __setups of same names 8( */
209 if (line[n] == '\0' || line[n] == '=')
210 had_early_param = 1;
211 } else if (!p->setup_func) {
212 printk(KERN_WARNING "Parameter %s is obsolete,"
213 " ignored\n", p->str);
214 return 1;
215 } else if (p->setup_func(line + n))
216 return 1;
218 p++;
219 } while (p < __setup_end);
221 return had_early_param;
225 * This should be approx 2 Bo*oMips to start (note initial shift), and will
226 * still work even if initially too large, it will just take slightly longer
228 unsigned long loops_per_jiffy = (1<<12);
230 EXPORT_SYMBOL(loops_per_jiffy);
232 static int __init debug_kernel(char *str)
234 console_loglevel = 10;
235 return 0;
238 static int __init quiet_kernel(char *str)
240 console_loglevel = 4;
241 return 0;
244 early_param("debug", debug_kernel);
245 early_param("quiet", quiet_kernel);
247 static int __init loglevel(char *str)
249 get_option(&str, &console_loglevel);
250 return 0;
253 early_param("loglevel", loglevel);
256 * Unknown boot options get handed to init, unless they look like
257 * failed parameters
259 static int __init unknown_bootoption(char *param, char *val)
261 /* Change NUL term back to "=", to make "param" the whole string. */
262 if (val) {
263 /* param=val or param="val"? */
264 if (val == param+strlen(param)+1)
265 val[-1] = '=';
266 else if (val == param+strlen(param)+2) {
267 val[-2] = '=';
268 memmove(val-1, val, strlen(val)+1);
269 val--;
270 } else
271 BUG();
274 /* Handle obsolete-style parameters */
275 if (obsolete_checksetup(param))
276 return 0;
279 * Preemptive maintenance for "why didn't my misspelled command
280 * line work?"
282 if (strchr(param, '.') && (!val || strchr(param, '.') < val)) {
283 printk(KERN_ERR "Unknown boot option `%s': ignoring\n", param);
284 return 0;
287 if (panic_later)
288 return 0;
290 if (val) {
291 /* Environment option */
292 unsigned int i;
293 for (i = 0; envp_init[i]; i++) {
294 if (i == MAX_INIT_ENVS) {
295 panic_later = "Too many boot env vars at `%s'";
296 panic_param = param;
298 if (!strncmp(param, envp_init[i], val - param))
299 break;
301 envp_init[i] = param;
302 } else {
303 /* Command line option */
304 unsigned int i;
305 for (i = 0; argv_init[i]; i++) {
306 if (i == MAX_INIT_ARGS) {
307 panic_later = "Too many boot init vars at `%s'";
308 panic_param = param;
311 argv_init[i] = param;
313 return 0;
316 #ifdef CONFIG_DEBUG_PAGEALLOC
317 int __read_mostly debug_pagealloc_enabled = 0;
318 #endif
320 static int __init init_setup(char *str)
322 unsigned int i;
324 execute_command = str;
326 * In case LILO is going to boot us with default command line,
327 * it prepends "auto" before the whole cmdline which makes
328 * the shell think it should execute a script with such name.
329 * So we ignore all arguments entered _before_ init=... [MJ]
331 for (i = 1; i < MAX_INIT_ARGS; i++)
332 argv_init[i] = NULL;
333 return 1;
335 __setup("init=", init_setup);
337 static int __init rdinit_setup(char *str)
339 unsigned int i;
341 ramdisk_execute_command = str;
342 /* See "auto" comment in init_setup */
343 for (i = 1; i < MAX_INIT_ARGS; i++)
344 argv_init[i] = NULL;
345 return 1;
347 __setup("rdinit=", rdinit_setup);
349 #ifndef CONFIG_SMP
351 #ifdef CONFIG_X86_LOCAL_APIC
352 static void __init smp_init(void)
354 APIC_init_uniprocessor();
356 #else
357 #define smp_init() do { } while (0)
358 #endif
360 static inline void setup_per_cpu_areas(void) { }
361 static inline void setup_nr_cpu_ids(void) { }
362 static inline void smp_prepare_cpus(unsigned int maxcpus) { }
364 #else
366 #if NR_CPUS > BITS_PER_LONG
367 cpumask_t cpu_mask_all __read_mostly = CPU_MASK_ALL;
368 EXPORT_SYMBOL(cpu_mask_all);
369 #endif
371 /* Setup number of possible processor ids */
372 int nr_cpu_ids __read_mostly = NR_CPUS;
373 EXPORT_SYMBOL(nr_cpu_ids);
375 /* An arch may set nr_cpu_ids earlier if needed, so this would be redundant */
376 static void __init setup_nr_cpu_ids(void)
378 nr_cpu_ids = find_last_bit(cpumask_bits(cpu_possible_mask),NR_CPUS) + 1;
381 #ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
382 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
384 EXPORT_SYMBOL(__per_cpu_offset);
386 static void __init setup_per_cpu_areas(void)
388 unsigned long size, i;
389 char *ptr;
390 unsigned long nr_possible_cpus = num_possible_cpus();
392 /* Copy section for each CPU (we discard the original) */
393 size = ALIGN(PERCPU_ENOUGH_ROOM, PAGE_SIZE);
394 ptr = alloc_bootmem_pages(size * nr_possible_cpus);
396 for_each_possible_cpu(i) {
397 __per_cpu_offset[i] = ptr - __per_cpu_start;
398 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
399 ptr += size;
402 #endif /* CONFIG_HAVE_SETUP_PER_CPU_AREA */
404 /* Called by boot processor to activate the rest. */
405 static void __init smp_init(void)
407 unsigned int cpu;
410 * Set up the current CPU as possible to migrate to.
411 * The other ones will be done by cpu_up/cpu_down()
413 set_cpu_active(smp_processor_id(), true);
415 /* FIXME: This should be done in userspace --RR */
416 for_each_present_cpu(cpu) {
417 if (num_online_cpus() >= setup_max_cpus)
418 break;
419 if (!cpu_online(cpu))
420 cpu_up(cpu);
423 /* Any cleanup work */
424 printk(KERN_INFO "Brought up %ld CPUs\n", (long)num_online_cpus());
425 smp_cpus_done(setup_max_cpus);
428 #endif
431 * We need to store the untouched command line for future reference.
432 * We also need to store the touched command line since the parameter
433 * parsing is performed in place, and we should allow a component to
434 * store reference of name/value for future reference.
436 static void __init setup_command_line(char *command_line)
438 saved_command_line = alloc_bootmem(strlen (boot_command_line)+1);
439 static_command_line = alloc_bootmem(strlen (command_line)+1);
440 strcpy (saved_command_line, boot_command_line);
441 strcpy (static_command_line, command_line);
445 * We need to finalize in a non-__init function or else race conditions
446 * between the root thread and the init thread may cause start_kernel to
447 * be reaped by free_initmem before the root thread has proceeded to
448 * cpu_idle.
450 * gcc-3.4 accidentally inlines this function, so use noinline.
453 static noinline void __init_refok rest_init(void)
454 __releases(kernel_lock)
456 int pid;
458 kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND);
459 numa_default_policy();
460 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
461 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
462 unlock_kernel();
465 * The boot idle thread must execute schedule()
466 * at least once to get things moving:
468 init_idle_bootup_task(current);
469 rcu_scheduler_starting();
470 preempt_enable_no_resched();
471 schedule();
472 preempt_disable();
474 /* Call into cpu_idle with preempt disabled */
475 cpu_idle();
478 /* Check for early params. */
479 static int __init do_early_param(char *param, char *val)
481 struct obs_kernel_param *p;
483 for (p = __setup_start; p < __setup_end; p++) {
484 if ((p->early && strcmp(param, p->str) == 0) ||
485 (strcmp(param, "console") == 0 &&
486 strcmp(p->str, "earlycon") == 0)
488 if (p->setup_func(val) != 0)
489 printk(KERN_WARNING
490 "Malformed early option '%s'\n", param);
493 /* We accept everything at this stage. */
494 return 0;
497 void __init parse_early_options(char *cmdline)
499 parse_args("early options", cmdline, NULL, 0, do_early_param);
502 /* Arch code calls this early on, or if not, just before other parsing. */
503 void __init parse_early_param(void)
505 static __initdata int done = 0;
506 static __initdata char tmp_cmdline[COMMAND_LINE_SIZE];
508 if (done)
509 return;
511 /* All fall through to do_early_param. */
512 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
513 parse_early_options(tmp_cmdline);
514 done = 1;
518 * Activate the first processor.
521 static void __init boot_cpu_init(void)
523 int cpu = smp_processor_id();
524 /* Mark the boot cpu "present", "online" etc for SMP and UP case */
525 set_cpu_online(cpu, true);
526 set_cpu_present(cpu, true);
527 set_cpu_possible(cpu, true);
530 void __init __weak smp_setup_processor_id(void)
534 void __init __weak thread_info_cache_init(void)
539 * Set up kernel memory allocators
541 static void __init mm_init(void)
544 * page_cgroup requires countinous pages as memmap
545 * and it's bigger than MAX_ORDER unless SPARSEMEM.
547 page_cgroup_init_flatmem();
548 mem_init();
549 kmem_cache_init();
550 pgtable_cache_init();
551 vmalloc_init();
554 asmlinkage void __init start_kernel(void)
556 char * command_line;
557 extern struct kernel_param __start___param[], __stop___param[];
559 smp_setup_processor_id();
562 * Need to run as early as possible, to initialize the
563 * lockdep hash:
565 lockdep_init();
566 debug_objects_early_init();
569 * Set up the the initial canary ASAP:
571 boot_init_stack_canary();
573 cgroup_init_early();
575 local_irq_disable();
576 early_boot_irqs_off();
577 early_init_irq_lock_class();
580 * Interrupts are still disabled. Do necessary setups, then
581 * enable them
583 lock_kernel();
584 tick_init();
585 boot_cpu_init();
586 page_address_init();
587 printk(KERN_NOTICE "%s", linux_banner);
588 setup_arch(&command_line);
589 mm_init_owner(&init_mm, &init_task);
590 setup_command_line(command_line);
591 setup_per_cpu_areas();
592 setup_nr_cpu_ids();
593 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
595 build_all_zonelists();
596 page_alloc_init();
598 printk(KERN_NOTICE "Kernel command line: %s\n", boot_command_line);
599 parse_early_param();
600 parse_args("Booting kernel", static_command_line, __start___param,
601 __stop___param - __start___param,
602 &unknown_bootoption);
604 * These use large bootmem allocations and must precede
605 * kmem_cache_init()
607 pidhash_init();
608 vfs_caches_init_early();
609 sort_main_extable();
610 trap_init();
611 mm_init();
613 * Set up the scheduler prior starting any interrupts (such as the
614 * timer interrupt). Full topology setup happens at smp_init()
615 * time - but meanwhile we still have a functioning scheduler.
617 sched_init();
619 * Disable preemption - early bootup scheduling is extremely
620 * fragile until we cpu_idle() for the first time.
622 preempt_disable();
623 if (!irqs_disabled()) {
624 printk(KERN_WARNING "start_kernel(): bug: interrupts were "
625 "enabled *very* early, fixing it\n");
626 local_irq_disable();
628 rcu_init();
629 /* init some links before init_ISA_irqs() */
630 early_irq_init();
631 init_IRQ();
632 prio_tree_init();
633 init_timers();
634 hrtimers_init();
635 softirq_init();
636 timekeeping_init();
637 time_init();
638 sched_clock_init();
639 profile_init();
640 if (!irqs_disabled())
641 printk(KERN_CRIT "start_kernel(): bug: interrupts were "
642 "enabled early\n");
643 early_boot_irqs_on();
644 local_irq_enable();
645 kmem_cache_init_late();
648 * HACK ALERT! This is early. We're enabling the console before
649 * we've done PCI setups etc, and console_init() must be aware of
650 * this. But we do want output early, in case something goes wrong.
652 console_init();
653 if (panic_later)
654 panic(panic_later, panic_param);
656 lockdep_info();
659 * Need to run this when irqs are enabled, because it wants
660 * to self-test [hard/soft]-irqs on/off lock inversion bugs
661 * too:
663 locking_selftest();
665 #ifdef CONFIG_BLK_DEV_INITRD
666 if (initrd_start && !initrd_below_start_ok &&
667 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
668 printk(KERN_CRIT "initrd overwritten (0x%08lx < 0x%08lx) - "
669 "disabling it.\n",
670 page_to_pfn(virt_to_page((void *)initrd_start)),
671 min_low_pfn);
672 initrd_start = 0;
674 #endif
675 page_cgroup_init();
676 enable_debug_pagealloc();
677 cpu_hotplug_init();
678 kmemtrace_init();
679 kmemleak_init();
680 debug_objects_mem_init();
681 idr_init_cache();
682 setup_per_cpu_pageset();
683 numa_policy_init();
684 if (late_time_init)
685 late_time_init();
686 calibrate_delay();
687 pidmap_init();
688 anon_vma_init();
689 #ifdef CONFIG_X86
690 if (efi_enabled)
691 efi_enter_virtual_mode();
692 #endif
693 thread_info_cache_init();
694 cred_init();
695 fork_init(num_physpages);
696 proc_caches_init();
697 buffer_init();
698 key_init();
699 security_init();
700 vfs_caches_init(num_physpages);
701 radix_tree_init();
702 signals_init();
703 /* rootfs populating might need page-writeback */
704 page_writeback_init();
705 #ifdef CONFIG_PROC_FS
706 proc_root_init();
707 #endif
708 cgroup_init();
709 cpuset_init();
710 taskstats_init_early();
711 delayacct_init();
713 check_bugs();
715 acpi_early_init(); /* before LAPIC and SMP init */
717 ftrace_init();
719 /* Do the rest non-__init'ed, we're now alive */
720 rest_init();
723 /* Call all constructor functions linked into the kernel. */
724 static void __init do_ctors(void)
726 #ifdef CONFIG_CONSTRUCTORS
727 ctor_fn_t *call = (ctor_fn_t *) __ctors_start;
729 for (; call < (ctor_fn_t *) __ctors_end; call++)
730 (*call)();
731 #endif
734 int initcall_debug;
735 core_param(initcall_debug, initcall_debug, bool, 0644);
737 int do_one_initcall(initcall_t fn)
739 int count = preempt_count();
740 ktime_t calltime, delta, rettime;
741 char msgbuf[64];
742 struct boot_trace_call call;
743 struct boot_trace_ret ret;
745 if (initcall_debug) {
746 call.caller = task_pid_nr(current);
747 printk("calling %pF @ %i\n", fn, call.caller);
748 calltime = ktime_get();
749 trace_boot_call(&call, fn);
750 enable_boot_trace();
753 ret.result = fn();
755 if (initcall_debug) {
756 disable_boot_trace();
757 rettime = ktime_get();
758 delta = ktime_sub(rettime, calltime);
759 ret.duration = (unsigned long long) ktime_to_ns(delta) >> 10;
760 trace_boot_ret(&ret, fn);
761 printk("initcall %pF returned %d after %Ld usecs\n", fn,
762 ret.result, ret.duration);
765 msgbuf[0] = 0;
767 if (ret.result && ret.result != -ENODEV && initcall_debug)
768 sprintf(msgbuf, "error code %d ", ret.result);
770 if (preempt_count() != count) {
771 strlcat(msgbuf, "preemption imbalance ", sizeof(msgbuf));
772 preempt_count() = count;
774 if (irqs_disabled()) {
775 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf));
776 local_irq_enable();
778 if (msgbuf[0]) {
779 printk("initcall %pF returned with %s\n", fn, msgbuf);
782 return ret.result;
786 extern initcall_t __initcall_start[], __initcall_end[], __early_initcall_end[];
788 static void __init do_initcalls(void)
790 initcall_t *call;
792 for (call = __early_initcall_end; call < __initcall_end; call++)
793 do_one_initcall(*call);
795 /* Make sure there is no pending stuff from the initcall sequence */
796 flush_scheduled_work();
800 * Ok, the machine is now initialized. None of the devices
801 * have been touched yet, but the CPU subsystem is up and
802 * running, and memory and process management works.
804 * Now we can finally start doing some real work..
806 static void __init do_basic_setup(void)
808 rcu_init_sched(); /* needed by module_init stage. */
809 init_workqueues();
810 cpuset_init_smp();
811 usermodehelper_init();
812 driver_init();
813 init_irq_proc();
814 do_ctors();
815 do_initcalls();
818 static void __init do_pre_smp_initcalls(void)
820 initcall_t *call;
822 for (call = __initcall_start; call < __early_initcall_end; call++)
823 do_one_initcall(*call);
826 static void run_init_process(char *init_filename)
828 argv_init[0] = init_filename;
829 kernel_execve(init_filename, argv_init, envp_init);
832 /* This is a non __init function. Force it to be noinline otherwise gcc
833 * makes it inline to init() and it becomes part of init.text section
835 static noinline int init_post(void)
836 __releases(kernel_lock)
838 /* need to finish all async __init code before freeing the memory */
839 async_synchronize_full();
840 free_initmem();
841 unlock_kernel();
842 mark_rodata_ro();
843 system_state = SYSTEM_RUNNING;
844 numa_default_policy();
846 if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
847 printk(KERN_WARNING "Warning: unable to open an initial console.\n");
849 (void) sys_dup(0);
850 (void) sys_dup(0);
852 current->signal->flags |= SIGNAL_UNKILLABLE;
854 if (ramdisk_execute_command) {
855 run_init_process(ramdisk_execute_command);
856 printk(KERN_WARNING "Failed to execute %s\n",
857 ramdisk_execute_command);
861 * We try each of these until one succeeds.
863 * The Bourne shell can be used instead of init if we are
864 * trying to recover a really broken machine.
866 if (execute_command) {
867 run_init_process(execute_command);
868 printk(KERN_WARNING "Failed to execute %s. Attempting "
869 "defaults...\n", execute_command);
871 run_init_process("/sbin/init");
872 run_init_process("/etc/init");
873 run_init_process("/bin/init");
874 run_init_process("/bin/sh");
876 panic("No init found. Try passing init= option to kernel.");
879 static int __init kernel_init(void * unused)
881 lock_kernel();
884 * init can allocate pages on any node
886 set_mems_allowed(node_possible_map);
888 * init can run on any cpu.
890 set_cpus_allowed_ptr(current, cpu_all_mask);
892 * Tell the world that we're going to be the grim
893 * reaper of innocent orphaned children.
895 * We don't want people to have to make incorrect
896 * assumptions about where in the task array this
897 * can be found.
899 init_pid_ns.child_reaper = current;
901 cad_pid = task_pid(current);
903 smp_prepare_cpus(setup_max_cpus);
905 do_pre_smp_initcalls();
906 start_boot_trace();
908 smp_init();
909 sched_init_smp();
911 do_basic_setup();
914 * check if there is an early userspace init. If yes, let it do all
915 * the work
918 if (!ramdisk_execute_command)
919 ramdisk_execute_command = "/init";
921 if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
922 ramdisk_execute_command = NULL;
923 prepare_namespace();
927 * Ok, we have completed the initial bootup, and
928 * we're essentially up and running. Get rid of the
929 * initmem segments and start the user-mode stuff..
932 init_post();
933 return 0;