Showing error 1694

User: Jiri Slaby
Error type: Double Lock
Error type description: Some lock is locked twice unintentionally in a sequence
File location: init/main.c
Line in file: 601
Project: Linux Kernel
Project version: 2.6.28
Tools: Smatch (1.59)
Entered: 2013-09-10 14:01:52 UTC


Source:

  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
 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/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/bootmem.h>
 26#include <linux/tty.h>
 27#include <linux/gfp.h>
 28#include <linux/percpu.h>
 29#include <linux/kmod.h>
 30#include <linux/vmalloc.h>
 31#include <linux/kernel_stat.h>
 32#include <linux/start_kernel.h>
 33#include <linux/security.h>
 34#include <linux/smp.h>
 35#include <linux/workqueue.h>
 36#include <linux/profile.h>
 37#include <linux/rcupdate.h>
 38#include <linux/moduleparam.h>
 39#include <linux/kallsyms.h>
 40#include <linux/writeback.h>
 41#include <linux/cpu.h>
 42#include <linux/cpuset.h>
 43#include <linux/cgroup.h>
 44#include <linux/efi.h>
 45#include <linux/tick.h>
 46#include <linux/interrupt.h>
 47#include <linux/taskstats_kern.h>
 48#include <linux/delayacct.h>
 49#include <linux/unistd.h>
 50#include <linux/rmap.h>
 51#include <linux/mempolicy.h>
 52#include <linux/key.h>
 53#include <linux/unwind.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/pid_namespace.h>
 60#include <linux/device.h>
 61#include <linux/kthread.h>
 62#include <linux/sched.h>
 63#include <linux/signal.h>
 64#include <linux/idr.h>
 65#include <linux/ftrace.h>
 66
 67#include <asm/io.h>
 68#include <asm/bugs.h>
 69#include <asm/setup.h>
 70#include <asm/sections.h>
 71#include <asm/cacheflush.h>
 72
 73#ifdef CONFIG_X86_LOCAL_APIC
 74#include <asm/smp.h>
 75#endif
 76
 77/*
 78 * This is one of the first .c files built. Error out early if we have compiler
 79 * trouble.
 80 */
 81
 82#if __GNUC__ == 4 && __GNUC_MINOR__ == 1 && __GNUC_PATCHLEVEL__ == 0
 83#warning gcc-4.1.0 is known to miscompile the kernel.  A different compiler version is recommended.
 84#endif
 85
 86static int kernel_init(void *);
 87
 88extern void init_IRQ(void);
 89extern void fork_init(unsigned long);
 90extern void mca_init(void);
 91extern void sbus_init(void);
 92extern void prio_tree_init(void);
 93extern void radix_tree_init(void);
 94extern void free_initmem(void);
 95#ifdef        CONFIG_ACPI
 96extern void acpi_early_init(void);
 97#else
 98static inline void acpi_early_init(void) { }
 99#endif
100#ifndef CONFIG_DEBUG_RODATA
101static inline void mark_rodata_ro(void) { }
102#endif
103
104#ifdef CONFIG_TC
105extern void tc_init(void);
106#endif
107
108enum system_states system_state;
109EXPORT_SYMBOL(system_state);
110
111/*
112 * Boot command-line arguments
113 */
114#define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
115#define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
116
117extern void time_init(void);
118/* Default late time init is NULL. archs can override this later. */
119void (*late_time_init)(void);
120extern void softirq_init(void);
121
122/* Untouched command line saved by arch-specific code. */
123char __initdata boot_command_line[COMMAND_LINE_SIZE];
124/* Untouched saved command line (eg. for /proc) */
125char *saved_command_line;
126/* Command line for parameter parsing */
127static char *static_command_line;
128
129static char *execute_command;
130static char *ramdisk_execute_command;
131
132#ifdef CONFIG_SMP
133/* Setup configured maximum number of CPUs to activate */
134unsigned int __initdata setup_max_cpus = NR_CPUS;
135
136/*
137 * Setup routine for controlling SMP activation
138 *
139 * Command-line option of "nosmp" or "maxcpus=0" will disable SMP
140 * activation entirely (the MPS table probe still happens, though).
141 *
142 * Command-line option of "maxcpus=<NUM>", where <NUM> is an integer
143 * greater than 0, limits the maximum number of CPUs activated in
144 * SMP mode to <NUM>.
145 */
146#ifndef CONFIG_X86_IO_APIC
147static inline void disable_ioapic_setup(void) {};
148#endif
149
150static int __init nosmp(char *str)
151{
152        setup_max_cpus = 0;
153        disable_ioapic_setup();
154        return 0;
155}
156
157early_param("nosmp", nosmp);
158
159static int __init maxcpus(char *str)
160{
161        get_option(&str, &setup_max_cpus);
162        if (setup_max_cpus == 0)
163                disable_ioapic_setup();
164
165        return 0;
166}
167
168early_param("maxcpus", maxcpus);
169#else
170#define setup_max_cpus NR_CPUS
171#endif
172
173/*
174 * If set, this is an indication to the drivers that reset the underlying
175 * device before going ahead with the initialization otherwise driver might
176 * rely on the BIOS and skip the reset operation.
177 *
178 * This is useful if kernel is booting in an unreliable environment.
179 * For ex. kdump situaiton where previous kernel has crashed, BIOS has been
180 * skipped and devices will be in unknown state.
181 */
182unsigned int reset_devices;
183EXPORT_SYMBOL(reset_devices);
184
185static int __init set_reset_devices(char *str)
186{
187        reset_devices = 1;
188        return 1;
189}
190
191__setup("reset_devices", set_reset_devices);
192
193static char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
194char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
195static const char *panic_later, *panic_param;
196
197extern struct obs_kernel_param __setup_start[], __setup_end[];
198
199static int __init obsolete_checksetup(char *line)
200{
201        struct obs_kernel_param *p;
202        int had_early_param = 0;
203
204        p = __setup_start;
205        do {
206                int n = strlen(p->str);
207                if (!strncmp(line, p->str, n)) {
208                        if (p->early) {
209                                /* Already done in parse_early_param?
210                                 * (Needs exact match on param part).
211                                 * Keep iterating, as we can have early
212                                 * params and __setups of same names 8( */
213                                if (line[n] == '\0' || line[n] == '=')
214                                        had_early_param = 1;
215                        } else if (!p->setup_func) {
216                                printk(KERN_WARNING "Parameter %s is obsolete,"
217                                       " ignored\n", p->str);
218                                return 1;
219                        } else if (p->setup_func(line + n))
220                                return 1;
221                }
222                p++;
223        } while (p < __setup_end);
224
225        return had_early_param;
226}
227
228/*
229 * This should be approx 2 Bo*oMips to start (note initial shift), and will
230 * still work even if initially too large, it will just take slightly longer
231 */
232unsigned long loops_per_jiffy = (1<<12);
233
234EXPORT_SYMBOL(loops_per_jiffy);
235
236static int __init debug_kernel(char *str)
237{
238        console_loglevel = 10;
239        return 0;
240}
241
242static int __init quiet_kernel(char *str)
243{
244        console_loglevel = 4;
245        return 0;
246}
247
248early_param("debug", debug_kernel);
249early_param("quiet", quiet_kernel);
250
251static int __init loglevel(char *str)
252{
253        get_option(&str, &console_loglevel);
254        return 0;
255}
256
257early_param("loglevel", loglevel);
258
259/*
260 * Unknown boot options get handed to init, unless they look like
261 * failed parameters
262 */
263static int __init unknown_bootoption(char *param, char *val)
264{
265        /* Change NUL term back to "=", to make "param" the whole string. */
266        if (val) {
267                /* param=val or param="val"? */
268                if (val == param+strlen(param)+1)
269                        val[-1] = '=';
270                else if (val == param+strlen(param)+2) {
271                        val[-2] = '=';
272                        memmove(val-1, val, strlen(val)+1);
273                        val--;
274                } else
275                        BUG();
276        }
277
278        /* Handle obsolete-style parameters */
279        if (obsolete_checksetup(param))
280                return 0;
281
282        /*
283         * Preemptive maintenance for "why didn't my misspelled command
284         * line work?"
285         */
286        if (strchr(param, '.') && (!val || strchr(param, '.') < val)) {
287                printk(KERN_ERR "Unknown boot option `%s': ignoring\n", param);
288                return 0;
289        }
290
291        if (panic_later)
292                return 0;
293
294        if (val) {
295                /* Environment option */
296                unsigned int i;
297                for (i = 0; envp_init[i]; i++) {
298                        if (i == MAX_INIT_ENVS) {
299                                panic_later = "Too many boot env vars at `%s'";
300                                panic_param = param;
301                        }
302                        if (!strncmp(param, envp_init[i], val - param))
303                                break;
304                }
305                envp_init[i] = param;
306        } else {
307                /* Command line option */
308                unsigned int i;
309                for (i = 0; argv_init[i]; i++) {
310                        if (i == MAX_INIT_ARGS) {
311                                panic_later = "Too many boot init vars at `%s'";
312                                panic_param = param;
313                        }
314                }
315                argv_init[i] = param;
316        }
317        return 0;
318}
319
320#ifdef CONFIG_DEBUG_PAGEALLOC
321int __read_mostly debug_pagealloc_enabled = 0;
322#endif
323
324static int __init init_setup(char *str)
325{
326        unsigned int i;
327
328        execute_command = str;
329        /*
330         * In case LILO is going to boot us with default command line,
331         * it prepends "auto" before the whole cmdline which makes
332         * the shell think it should execute a script with such name.
333         * So we ignore all arguments entered _before_ init=... [MJ]
334         */
335        for (i = 1; i < MAX_INIT_ARGS; i++)
336                argv_init[i] = NULL;
337        return 1;
338}
339__setup("init=", init_setup);
340
341static int __init rdinit_setup(char *str)
342{
343        unsigned int i;
344
345        ramdisk_execute_command = str;
346        /* See "auto" comment in init_setup */
347        for (i = 1; i < MAX_INIT_ARGS; i++)
348                argv_init[i] = NULL;
349        return 1;
350}
351__setup("rdinit=", rdinit_setup);
352
353#ifndef CONFIG_SMP
354
355#ifdef CONFIG_X86_LOCAL_APIC
356static void __init smp_init(void)
357{
358        APIC_init_uniprocessor();
359}
360#else
361#define smp_init()        do { } while (0)
362#endif
363
364static inline void setup_per_cpu_areas(void) { }
365static inline void setup_nr_cpu_ids(void) { }
366static inline void smp_prepare_cpus(unsigned int maxcpus) { }
367
368#else
369
370#if NR_CPUS > BITS_PER_LONG
371cpumask_t cpu_mask_all __read_mostly = CPU_MASK_ALL;
372EXPORT_SYMBOL(cpu_mask_all);
373#endif
374
375/* Setup number of possible processor ids */
376int nr_cpu_ids __read_mostly = NR_CPUS;
377EXPORT_SYMBOL(nr_cpu_ids);
378
379/* An arch may set nr_cpu_ids earlier if needed, so this would be redundant */
380static void __init setup_nr_cpu_ids(void)
381{
382        int cpu, highest_cpu = 0;
383
384        for_each_possible_cpu(cpu)
385                highest_cpu = cpu;
386
387        nr_cpu_ids = highest_cpu + 1;
388}
389
390#ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
391unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
392
393EXPORT_SYMBOL(__per_cpu_offset);
394
395static void __init setup_per_cpu_areas(void)
396{
397        unsigned long size, i;
398        char *ptr;
399        unsigned long nr_possible_cpus = num_possible_cpus();
400
401        /* Copy section for each CPU (we discard the original) */
402        size = ALIGN(PERCPU_ENOUGH_ROOM, PAGE_SIZE);
403        ptr = alloc_bootmem_pages(size * nr_possible_cpus);
404
405        for_each_possible_cpu(i) {
406                __per_cpu_offset[i] = ptr - __per_cpu_start;
407                memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
408                ptr += size;
409        }
410}
411#endif /* CONFIG_HAVE_SETUP_PER_CPU_AREA */
412
413/* Called by boot processor to activate the rest. */
414static void __init smp_init(void)
415{
416        unsigned int cpu;
417
418        /*
419         * Set up the current CPU as possible to migrate to.
420         * The other ones will be done by cpu_up/cpu_down()
421         */
422        cpu = smp_processor_id();
423        cpu_set(cpu, cpu_active_map);
424
425        /* FIXME: This should be done in userspace --RR */
426        for_each_present_cpu(cpu) {
427                if (num_online_cpus() >= setup_max_cpus)
428                        break;
429                if (!cpu_online(cpu))
430                        cpu_up(cpu);
431        }
432
433        /* Any cleanup work */
434        printk(KERN_INFO "Brought up %ld CPUs\n", (long)num_online_cpus());
435        smp_cpus_done(setup_max_cpus);
436}
437
438#endif
439
440/*
441 * We need to store the untouched command line for future reference.
442 * We also need to store the touched command line since the parameter
443 * parsing is performed in place, and we should allow a component to
444 * store reference of name/value for future reference.
445 */
446static void __init setup_command_line(char *command_line)
447{
448        saved_command_line = alloc_bootmem(strlen (boot_command_line)+1);
449        static_command_line = alloc_bootmem(strlen (command_line)+1);
450        strcpy (saved_command_line, boot_command_line);
451        strcpy (static_command_line, command_line);
452}
453
454/*
455 * We need to finalize in a non-__init function or else race conditions
456 * between the root thread and the init thread may cause start_kernel to
457 * be reaped by free_initmem before the root thread has proceeded to
458 * cpu_idle.
459 *
460 * gcc-3.4 accidentally inlines this function, so use noinline.
461 */
462
463static void noinline __init_refok rest_init(void)
464        __releases(kernel_lock)
465{
466        int pid;
467
468        kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND);
469        numa_default_policy();
470        pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
471        kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
472        unlock_kernel();
473
474        /*
475         * The boot idle thread must execute schedule()
476         * at least once to get things moving:
477         */
478        init_idle_bootup_task(current);
479        preempt_enable_no_resched();
480        schedule();
481        preempt_disable();
482
483        /* Call into cpu_idle with preempt disabled */
484        cpu_idle();
485}
486
487/* Check for early params. */
488static int __init do_early_param(char *param, char *val)
489{
490        struct obs_kernel_param *p;
491
492        for (p = __setup_start; p < __setup_end; p++) {
493                if ((p->early && strcmp(param, p->str) == 0) ||
494                    (strcmp(param, "console") == 0 &&
495                     strcmp(p->str, "earlycon") == 0)
496                ) {
497                        if (p->setup_func(val) != 0)
498                                printk(KERN_WARNING
499                                       "Malformed early option '%s'\n", param);
500                }
501        }
502        /* We accept everything at this stage. */
503        return 0;
504}
505
506/* Arch code calls this early on, or if not, just before other parsing. */
507void __init parse_early_param(void)
508{
509        static __initdata int done = 0;
510        static __initdata char tmp_cmdline[COMMAND_LINE_SIZE];
511
512        if (done)
513                return;
514
515        /* All fall through to do_early_param. */
516        strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
517        parse_args("early options", tmp_cmdline, NULL, 0, do_early_param);
518        done = 1;
519}
520
521/*
522 *        Activate the first processor.
523 */
524
525static void __init boot_cpu_init(void)
526{
527        int cpu = smp_processor_id();
528        /* Mark the boot cpu "present", "online" etc for SMP and UP case */
529        cpu_set(cpu, cpu_online_map);
530        cpu_set(cpu, cpu_present_map);
531        cpu_set(cpu, cpu_possible_map);
532}
533
534void __init __weak smp_setup_processor_id(void)
535{
536}
537
538void __init __weak thread_info_cache_init(void)
539{
540}
541
542asmlinkage void __init start_kernel(void)
543{
544        char * command_line;
545        extern struct kernel_param __start___param[], __stop___param[];
546
547        smp_setup_processor_id();
548
549        /*
550         * Need to run as early as possible, to initialize the
551         * lockdep hash:
552         */
553        unwind_init();
554        lockdep_init();
555        debug_objects_early_init();
556        cgroup_init_early();
557
558        local_irq_disable();
559        early_boot_irqs_off();
560        early_init_irq_lock_class();
561
562/*
563 * Interrupts are still disabled. Do necessary setups, then
564 * enable them
565 */
566        lock_kernel();
567        tick_init();
568        boot_cpu_init();
569        page_address_init();
570        printk(KERN_NOTICE);
571        printk(linux_banner);
572        setup_arch(&command_line);
573        mm_init_owner(&init_mm, &init_task);
574        setup_command_line(command_line);
575        unwind_setup();
576        setup_per_cpu_areas();
577        setup_nr_cpu_ids();
578        smp_prepare_boot_cpu();        /* arch-specific boot-cpu hooks */
579
580        /*
581         * Set up the scheduler prior starting any interrupts (such as the
582         * timer interrupt). Full topology setup happens at smp_init()
583         * time - but meanwhile we still have a functioning scheduler.
584         */
585        sched_init();
586        /*
587         * Disable preemption - early bootup scheduling is extremely
588         * fragile until we cpu_idle() for the first time.
589         */
590        preempt_disable();
591        build_all_zonelists();
592        page_alloc_init();
593        printk(KERN_NOTICE "Kernel command line: %s\n", boot_command_line);
594        parse_early_param();
595        parse_args("Booting kernel", static_command_line, __start___param,
596                   __stop___param - __start___param,
597                   &unknown_bootoption);
598        if (!irqs_disabled()) {
599                printk(KERN_WARNING "start_kernel(): bug: interrupts were "
600                                "enabled *very* early, fixing it\n");
601                local_irq_disable();
602        }
603        sort_main_extable();
604        trap_init();
605        rcu_init();
606        init_IRQ();
607        pidhash_init();
608        init_timers();
609        hrtimers_init();
610        softirq_init();
611        timekeeping_init();
612        time_init();
613        sched_clock_init();
614        profile_init();
615        if (!irqs_disabled())
616                printk("start_kernel(): bug: interrupts were enabled early\n");
617        early_boot_irqs_on();
618        local_irq_enable();
619
620        /*
621         * HACK ALERT! This is early. We're enabling the console before
622         * we've done PCI setups etc, and console_init() must be aware of
623         * this. But we do want output early, in case something goes wrong.
624         */
625        console_init();
626        if (panic_later)
627                panic(panic_later, panic_param);
628
629        lockdep_info();
630
631        /*
632         * Need to run this when irqs are enabled, because it wants
633         * to self-test [hard/soft]-irqs on/off lock inversion bugs
634         * too:
635         */
636        locking_selftest();
637
638#ifdef CONFIG_BLK_DEV_INITRD
639        if (initrd_start && !initrd_below_start_ok &&
640            page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
641                printk(KERN_CRIT "initrd overwritten (0x%08lx < 0x%08lx) - "
642                    "disabling it.\n",
643                    page_to_pfn(virt_to_page((void *)initrd_start)),
644                    min_low_pfn);
645                initrd_start = 0;
646        }
647#endif
648        vmalloc_init();
649        vfs_caches_init_early();
650        cpuset_init_early();
651        page_cgroup_init();
652        mem_init();
653        enable_debug_pagealloc();
654        cpu_hotplug_init();
655        kmem_cache_init();
656        debug_objects_mem_init();
657        idr_init_cache();
658        setup_per_cpu_pageset();
659        numa_policy_init();
660        if (late_time_init)
661                late_time_init();
662        calibrate_delay();
663        pidmap_init();
664        pgtable_cache_init();
665        prio_tree_init();
666        anon_vma_init();
667#ifdef CONFIG_X86
668        if (efi_enabled)
669                efi_enter_virtual_mode();
670#endif
671        thread_info_cache_init();
672        fork_init(num_physpages);
673        proc_caches_init();
674        buffer_init();
675        key_init();
676        security_init();
677        vfs_caches_init(num_physpages);
678        radix_tree_init();
679        signals_init();
680        /* rootfs populating might need page-writeback */
681        page_writeback_init();
682#ifdef CONFIG_PROC_FS
683        proc_root_init();
684#endif
685        cgroup_init();
686        cpuset_init();
687        taskstats_init_early();
688        delayacct_init();
689
690        check_bugs();
691
692        acpi_early_init(); /* before LAPIC and SMP init */
693
694        ftrace_init();
695
696        /* Do the rest non-__init'ed, we're now alive */
697        rest_init();
698}
699
700static int initcall_debug;
701core_param(initcall_debug, initcall_debug, bool, 0644);
702
703int do_one_initcall(initcall_t fn)
704{
705        int count = preempt_count();
706        ktime_t delta;
707        char msgbuf[64];
708        struct boot_trace it;
709
710        if (initcall_debug) {
711                it.caller = task_pid_nr(current);
712                printk("calling  %pF @ %i\n", fn, it.caller);
713                it.calltime = ktime_get();
714        }
715
716        it.result = fn();
717
718        if (initcall_debug) {
719                it.rettime = ktime_get();
720                delta = ktime_sub(it.rettime, it.calltime);
721                it.duration = (unsigned long long) delta.tv64 >> 10;
722                printk("initcall %pF returned %d after %Ld usecs\n", fn,
723                        it.result, it.duration);
724                trace_boot(&it, fn);
725        }
726
727        msgbuf[0] = 0;
728
729        if (it.result && it.result != -ENODEV && initcall_debug)
730                sprintf(msgbuf, "error code %d ", it.result);
731
732        if (preempt_count() != count) {
733                strlcat(msgbuf, "preemption imbalance ", sizeof(msgbuf));
734                preempt_count() = count;
735        }
736        if (irqs_disabled()) {
737                strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf));
738                local_irq_enable();
739        }
740        if (msgbuf[0]) {
741                printk("initcall %pF returned with %s\n", fn, msgbuf);
742        }
743
744        return it.result;
745}
746
747
748extern initcall_t __initcall_start[], __initcall_end[], __early_initcall_end[];
749
750static void __init do_initcalls(void)
751{
752        initcall_t *call;
753
754        for (call = __early_initcall_end; call < __initcall_end; call++)
755                do_one_initcall(*call);
756
757        /* Make sure there is no pending stuff from the initcall sequence */
758        flush_scheduled_work();
759}
760
761/*
762 * Ok, the machine is now initialized. None of the devices
763 * have been touched yet, but the CPU subsystem is up and
764 * running, and memory and process management works.
765 *
766 * Now we can finally start doing some real work..
767 */
768static void __init do_basic_setup(void)
769{
770        rcu_init_sched(); /* needed by module_init stage. */
771        init_workqueues();
772        usermodehelper_init();
773        driver_init();
774        init_irq_proc();
775        do_initcalls();
776}
777
778static void __init do_pre_smp_initcalls(void)
779{
780        initcall_t *call;
781
782        for (call = __initcall_start; call < __early_initcall_end; call++)
783                do_one_initcall(*call);
784}
785
786static void run_init_process(char *init_filename)
787{
788        argv_init[0] = init_filename;
789        kernel_execve(init_filename, argv_init, envp_init);
790}
791
792/* This is a non __init function. Force it to be noinline otherwise gcc
793 * makes it inline to init() and it becomes part of init.text section
794 */
795static int noinline init_post(void)
796{
797        free_initmem();
798        unlock_kernel();
799        mark_rodata_ro();
800        system_state = SYSTEM_RUNNING;
801        numa_default_policy();
802
803        if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
804                printk(KERN_WARNING "Warning: unable to open an initial console.\n");
805
806        (void) sys_dup(0);
807        (void) sys_dup(0);
808
809        current->signal->flags |= SIGNAL_UNKILLABLE;
810
811        if (ramdisk_execute_command) {
812                run_init_process(ramdisk_execute_command);
813                printk(KERN_WARNING "Failed to execute %s\n",
814                                ramdisk_execute_command);
815        }
816
817        /*
818         * We try each of these until one succeeds.
819         *
820         * The Bourne shell can be used instead of init if we are
821         * trying to recover a really broken machine.
822         */
823        if (execute_command) {
824                run_init_process(execute_command);
825                printk(KERN_WARNING "Failed to execute %s.  Attempting "
826                                        "defaults...\n", execute_command);
827        }
828        run_init_process("/sbin/init");
829        run_init_process("/etc/init");
830        run_init_process("/bin/init");
831        run_init_process("/bin/sh");
832
833        panic("No init found.  Try passing init= option to kernel.");
834}
835
836static int __init kernel_init(void * unused)
837{
838        lock_kernel();
839        /*
840         * init can run on any cpu.
841         */
842        set_cpus_allowed_ptr(current, CPU_MASK_ALL_PTR);
843        /*
844         * Tell the world that we're going to be the grim
845         * reaper of innocent orphaned children.
846         *
847         * We don't want people to have to make incorrect
848         * assumptions about where in the task array this
849         * can be found.
850         */
851        init_pid_ns.child_reaper = current;
852
853        cad_pid = task_pid(current);
854
855        smp_prepare_cpus(setup_max_cpus);
856
857        do_pre_smp_initcalls();
858        start_boot_trace();
859
860        smp_init();
861        sched_init_smp();
862
863        cpuset_init_smp();
864
865        do_basic_setup();
866
867        /*
868         * check if there is an early userspace init.  If yes, let it do all
869         * the work
870         */
871
872        if (!ramdisk_execute_command)
873                ramdisk_execute_command = "/init";
874
875        if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
876                ramdisk_execute_command = NULL;
877                prepare_namespace();
878        }
879
880        /*
881         * Ok, we have completed the initial bootup, and
882         * we're essentially up and running. Get rid of the
883         * initmem segments and start the user-mode stuff..
884         */
885        stop_boot_trace();
886        init_post();
887        return 0;
888}