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-rw-r--r--kernel/init/main.c1035
1 files changed, 1035 insertions, 0 deletions
diff --git a/kernel/init/main.c b/kernel/init/main.c
new file mode 100644
index 000000000..0486a8e11
--- /dev/null
+++ b/kernel/init/main.c
@@ -0,0 +1,1035 @@
+/*
+ * linux/init/main.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * GK 2/5/95 - Changed to support mounting root fs via NFS
+ * Added initrd & change_root: Werner Almesberger & Hans Lermen, Feb '96
+ * Moan early if gcc is old, avoiding bogus kernels - Paul Gortmaker, May '96
+ * Simplified starting of init: Michael A. Griffith <grif@acm.org>
+ */
+
+#define DEBUG /* Enable initcall_debug */
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/kernel.h>
+#include <linux/syscalls.h>
+#include <linux/stackprotector.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/delay.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/initrd.h>
+#include <linux/bootmem.h>
+#include <linux/acpi.h>
+#include <linux/tty.h>
+#include <linux/percpu.h>
+#include <linux/kmod.h>
+#include <linux/vmalloc.h>
+#include <linux/kernel_stat.h>
+#include <linux/start_kernel.h>
+#include <linux/security.h>
+#include <linux/smp.h>
+#include <linux/profile.h>
+#include <linux/rcupdate.h>
+#include <linux/moduleparam.h>
+#include <linux/kallsyms.h>
+#include <linux/writeback.h>
+#include <linux/cpu.h>
+#include <linux/cpuset.h>
+#include <linux/cgroup.h>
+#include <linux/efi.h>
+#include <linux/tick.h>
+#include <linux/interrupt.h>
+#include <linux/taskstats_kern.h>
+#include <linux/delayacct.h>
+#include <linux/unistd.h>
+#include <linux/rmap.h>
+#include <linux/mempolicy.h>
+#include <linux/key.h>
+#include <linux/buffer_head.h>
+#include <linux/page_ext.h>
+#include <linux/debug_locks.h>
+#include <linux/debugobjects.h>
+#include <linux/lockdep.h>
+#include <linux/kmemleak.h>
+#include <linux/pid_namespace.h>
+#include <linux/device.h>
+#include <linux/kthread.h>
+#include <linux/sched.h>
+#include <linux/signal.h>
+#include <linux/idr.h>
+#include <linux/kgdb.h>
+#include <linux/ftrace.h>
+#include <linux/async.h>
+#include <linux/kmemcheck.h>
+#include <linux/sfi.h>
+#include <linux/shmem_fs.h>
+#include <linux/slab.h>
+#include <linux/perf_event.h>
+#include <linux/file.h>
+#include <linux/ptrace.h>
+#include <linux/blkdev.h>
+#include <linux/elevator.h>
+#include <linux/sched_clock.h>
+#include <linux/context_tracking.h>
+#include <linux/random.h>
+#include <linux/list.h>
+#include <linux/integrity.h>
+#include <linux/proc_ns.h>
+#include <linux/io.h>
+
+#include <asm/io.h>
+#include <asm/bugs.h>
+#include <asm/setup.h>
+#include <asm/sections.h>
+#include <asm/cacheflush.h>
+
+static int kernel_init(void *);
+
+extern void init_IRQ(void);
+extern void fork_init(void);
+extern void radix_tree_init(void);
+#ifndef CONFIG_DEBUG_RODATA
+static inline void mark_rodata_ro(void) { }
+#endif
+
+/*
+ * Debug helper: via this flag we know that we are in 'early bootup code'
+ * where only the boot processor is running with IRQ disabled. This means
+ * two things - IRQ must not be enabled before the flag is cleared and some
+ * operations which are not allowed with IRQ disabled are allowed while the
+ * flag is set.
+ */
+bool early_boot_irqs_disabled __read_mostly;
+
+enum system_states system_state __read_mostly;
+EXPORT_SYMBOL(system_state);
+
+/*
+ * Boot command-line arguments
+ */
+#define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
+#define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
+
+extern void time_init(void);
+/* Default late time init is NULL. archs can override this later. */
+void (*__initdata late_time_init)(void);
+
+/* Untouched command line saved by arch-specific code. */
+char __initdata boot_command_line[COMMAND_LINE_SIZE];
+/* Untouched saved command line (eg. for /proc) */
+char *saved_command_line;
+/* Command line for parameter parsing */
+static char *static_command_line;
+/* Command line for per-initcall parameter parsing */
+static char *initcall_command_line;
+
+static char *execute_command;
+static char *ramdisk_execute_command;
+
+/*
+ * Used to generate warnings if static_key manipulation functions are used
+ * before jump_label_init is called.
+ */
+bool static_key_initialized __read_mostly;
+EXPORT_SYMBOL_GPL(static_key_initialized);
+
+/*
+ * If set, this is an indication to the drivers that reset the underlying
+ * device before going ahead with the initialization otherwise driver might
+ * rely on the BIOS and skip the reset operation.
+ *
+ * This is useful if kernel is booting in an unreliable environment.
+ * For ex. kdump situation where previous kernel has crashed, BIOS has been
+ * skipped and devices will be in unknown state.
+ */
+unsigned int reset_devices;
+EXPORT_SYMBOL(reset_devices);
+
+static int __init set_reset_devices(char *str)
+{
+ reset_devices = 1;
+ return 1;
+}
+
+__setup("reset_devices", set_reset_devices);
+
+static const char *argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
+const char *envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
+static const char *panic_later, *panic_param;
+
+extern const struct obs_kernel_param __setup_start[], __setup_end[];
+
+static int __init obsolete_checksetup(char *line)
+{
+ const struct obs_kernel_param *p;
+ int had_early_param = 0;
+
+ p = __setup_start;
+ do {
+ int n = strlen(p->str);
+ if (parameqn(line, p->str, n)) {
+ if (p->early) {
+ /* Already done in parse_early_param?
+ * (Needs exact match on param part).
+ * Keep iterating, as we can have early
+ * params and __setups of same names 8( */
+ if (line[n] == '\0' || line[n] == '=')
+ had_early_param = 1;
+ } else if (!p->setup_func) {
+ pr_warn("Parameter %s is obsolete, ignored\n",
+ p->str);
+ return 1;
+ } else if (p->setup_func(line + n))
+ return 1;
+ }
+ p++;
+ } while (p < __setup_end);
+
+ return had_early_param;
+}
+
+/*
+ * This should be approx 2 Bo*oMips to start (note initial shift), and will
+ * still work even if initially too large, it will just take slightly longer
+ */
+unsigned long loops_per_jiffy = (1<<12);
+EXPORT_SYMBOL(loops_per_jiffy);
+
+static int __init debug_kernel(char *str)
+{
+ console_loglevel = CONSOLE_LOGLEVEL_DEBUG;
+ return 0;
+}
+
+static int __init quiet_kernel(char *str)
+{
+ console_loglevel = CONSOLE_LOGLEVEL_QUIET;
+ return 0;
+}
+
+early_param("debug", debug_kernel);
+early_param("quiet", quiet_kernel);
+
+static int __init loglevel(char *str)
+{
+ int newlevel;
+
+ /*
+ * Only update loglevel value when a correct setting was passed,
+ * to prevent blind crashes (when loglevel being set to 0) that
+ * are quite hard to debug
+ */
+ if (get_option(&str, &newlevel)) {
+ console_loglevel = newlevel;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+early_param("loglevel", loglevel);
+
+/* Change NUL term back to "=", to make "param" the whole string. */
+static int __init repair_env_string(char *param, char *val, const char *unused)
+{
+ if (val) {
+ /* param=val or param="val"? */
+ if (val == param+strlen(param)+1)
+ val[-1] = '=';
+ else if (val == param+strlen(param)+2) {
+ val[-2] = '=';
+ memmove(val-1, val, strlen(val)+1);
+ val--;
+ } else
+ BUG();
+ }
+ return 0;
+}
+
+/* Anything after -- gets handed straight to init. */
+static int __init set_init_arg(char *param, char *val, const char *unused)
+{
+ unsigned int i;
+
+ if (panic_later)
+ return 0;
+
+ repair_env_string(param, val, unused);
+
+ for (i = 0; argv_init[i]; i++) {
+ if (i == MAX_INIT_ARGS) {
+ panic_later = "init";
+ panic_param = param;
+ return 0;
+ }
+ }
+ argv_init[i] = param;
+ return 0;
+}
+
+/*
+ * Unknown boot options get handed to init, unless they look like
+ * unused parameters (modprobe will find them in /proc/cmdline).
+ */
+static int __init unknown_bootoption(char *param, char *val, const char *unused)
+{
+ repair_env_string(param, val, unused);
+
+ /* Handle obsolete-style parameters */
+ if (obsolete_checksetup(param))
+ return 0;
+
+ /* Unused module parameter. */
+ if (strchr(param, '.') && (!val || strchr(param, '.') < val))
+ return 0;
+
+ if (panic_later)
+ return 0;
+
+ if (val) {
+ /* Environment option */
+ unsigned int i;
+ for (i = 0; envp_init[i]; i++) {
+ if (i == MAX_INIT_ENVS) {
+ panic_later = "env";
+ panic_param = param;
+ }
+ if (!strncmp(param, envp_init[i], val - param))
+ break;
+ }
+ envp_init[i] = param;
+ } else {
+ /* Command line option */
+ unsigned int i;
+ for (i = 0; argv_init[i]; i++) {
+ if (i == MAX_INIT_ARGS) {
+ panic_later = "init";
+ panic_param = param;
+ }
+ }
+ argv_init[i] = param;
+ }
+ return 0;
+}
+
+static int __init init_setup(char *str)
+{
+ unsigned int i;
+
+ execute_command = str;
+ /*
+ * In case LILO is going to boot us with default command line,
+ * it prepends "auto" before the whole cmdline which makes
+ * the shell think it should execute a script with such name.
+ * So we ignore all arguments entered _before_ init=... [MJ]
+ */
+ for (i = 1; i < MAX_INIT_ARGS; i++)
+ argv_init[i] = NULL;
+ return 1;
+}
+__setup("init=", init_setup);
+
+static int __init rdinit_setup(char *str)
+{
+ unsigned int i;
+
+ ramdisk_execute_command = str;
+ /* See "auto" comment in init_setup */
+ for (i = 1; i < MAX_INIT_ARGS; i++)
+ argv_init[i] = NULL;
+ return 1;
+}
+__setup("rdinit=", rdinit_setup);
+
+#ifndef CONFIG_SMP
+static const unsigned int setup_max_cpus = NR_CPUS;
+static inline void setup_nr_cpu_ids(void) { }
+static inline void smp_prepare_cpus(unsigned int maxcpus) { }
+#endif
+
+/*
+ * We need to store the untouched command line for future reference.
+ * We also need to store the touched command line since the parameter
+ * parsing is performed in place, and we should allow a component to
+ * store reference of name/value for future reference.
+ */
+static void __init setup_command_line(char *command_line)
+{
+ saved_command_line =
+ memblock_virt_alloc(strlen(boot_command_line) + 1, 0);
+ initcall_command_line =
+ memblock_virt_alloc(strlen(boot_command_line) + 1, 0);
+ static_command_line = memblock_virt_alloc(strlen(command_line) + 1, 0);
+ strcpy(saved_command_line, boot_command_line);
+ strcpy(static_command_line, command_line);
+}
+
+/*
+ * We need to finalize in a non-__init function or else race conditions
+ * between the root thread and the init thread may cause start_kernel to
+ * be reaped by free_initmem before the root thread has proceeded to
+ * cpu_idle.
+ *
+ * gcc-3.4 accidentally inlines this function, so use noinline.
+ */
+
+static __initdata DECLARE_COMPLETION(kthreadd_done);
+
+static noinline void __init_refok rest_init(void)
+{
+ int pid;
+
+ rcu_scheduler_starting();
+ smpboot_thread_init();
+ /*
+ * We need to spawn init first so that it obtains pid 1, however
+ * the init task will end up wanting to create kthreads, which, if
+ * we schedule it before we create kthreadd, will OOPS.
+ */
+ kernel_thread(kernel_init, NULL, CLONE_FS);
+ numa_default_policy();
+ pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
+ rcu_read_lock();
+ kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
+ rcu_read_unlock();
+ complete(&kthreadd_done);
+
+ /*
+ * The boot idle thread must execute schedule()
+ * at least once to get things moving:
+ */
+ init_idle_bootup_task(current);
+ schedule_preempt_disabled();
+ /* Call into cpu_idle with preempt disabled */
+ cpu_startup_entry(CPUHP_ONLINE);
+}
+
+/* Check for early params. */
+static int __init do_early_param(char *param, char *val, const char *unused)
+{
+ const struct obs_kernel_param *p;
+
+ for (p = __setup_start; p < __setup_end; p++) {
+ if ((p->early && parameq(param, p->str)) ||
+ (strcmp(param, "console") == 0 &&
+ strcmp(p->str, "earlycon") == 0)
+ ) {
+ if (p->setup_func(val) != 0)
+ pr_warn("Malformed early option '%s'\n", param);
+ }
+ }
+ /* We accept everything at this stage. */
+ return 0;
+}
+
+void __init parse_early_options(char *cmdline)
+{
+ parse_args("early options", cmdline, NULL, 0, 0, 0, do_early_param);
+}
+
+/* Arch code calls this early on, or if not, just before other parsing. */
+void __init parse_early_param(void)
+{
+ static int done __initdata;
+ static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata;
+
+ if (done)
+ return;
+
+ /* All fall through to do_early_param. */
+ strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
+ parse_early_options(tmp_cmdline);
+ done = 1;
+}
+
+/*
+ * Activate the first processor.
+ */
+
+static void __init boot_cpu_init(void)
+{
+ int cpu = smp_processor_id();
+ /* Mark the boot cpu "present", "online" etc for SMP and UP case */
+ set_cpu_online(cpu, true);
+ set_cpu_active(cpu, true);
+ set_cpu_present(cpu, true);
+ set_cpu_possible(cpu, true);
+}
+
+void __init __weak smp_setup_processor_id(void)
+{
+}
+
+# if THREAD_SIZE >= PAGE_SIZE
+void __init __weak thread_info_cache_init(void)
+{
+}
+#endif
+
+/*
+ * Set up kernel memory allocators
+ */
+static void __init mm_init(void)
+{
+ /*
+ * page_ext requires contiguous pages,
+ * bigger than MAX_ORDER unless SPARSEMEM.
+ */
+ page_ext_init_flatmem();
+ mem_init();
+ kmem_cache_init();
+ percpu_init_late();
+ pgtable_init();
+ vmalloc_init();
+ ioremap_huge_init();
+}
+
+asmlinkage __visible void __init start_kernel(void)
+{
+ char *command_line;
+ char *after_dashes;
+
+ /*
+ * Need to run as early as possible, to initialize the
+ * lockdep hash:
+ */
+ lockdep_init();
+ set_task_stack_end_magic(&init_task);
+ smp_setup_processor_id();
+ debug_objects_early_init();
+
+ /*
+ * Set up the the initial canary ASAP:
+ */
+ boot_init_stack_canary();
+
+ cgroup_init_early();
+
+ local_irq_disable();
+ early_boot_irqs_disabled = true;
+
+/*
+ * Interrupts are still disabled. Do necessary setups, then
+ * enable them
+ */
+ boot_cpu_init();
+ page_address_init();
+ pr_notice("%s", linux_banner);
+ setup_arch(&command_line);
+ mm_init_cpumask(&init_mm);
+ setup_command_line(command_line);
+ setup_nr_cpu_ids();
+ setup_per_cpu_areas();
+ softirq_early_init();
+ smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
+
+ build_all_zonelists(NULL, NULL);
+ page_alloc_init();
+
+ pr_notice("Kernel command line: %s\n", boot_command_line);
+ parse_early_param();
+ after_dashes = parse_args("Booting kernel",
+ static_command_line, __start___param,
+ __stop___param - __start___param,
+ -1, -1, &unknown_bootoption);
+ if (!IS_ERR_OR_NULL(after_dashes))
+ parse_args("Setting init args", after_dashes, NULL, 0, -1, -1,
+ set_init_arg);
+
+ jump_label_init();
+
+ /*
+ * These use large bootmem allocations and must precede
+ * kmem_cache_init()
+ */
+ setup_log_buf(0);
+ pidhash_init();
+ vfs_caches_init_early();
+ sort_main_extable();
+ trap_init();
+ mm_init();
+
+ /*
+ * Set up the scheduler prior starting any interrupts (such as the
+ * timer interrupt). Full topology setup happens at smp_init()
+ * time - but meanwhile we still have a functioning scheduler.
+ */
+ sched_init();
+ /*
+ * Disable preemption - early bootup scheduling is extremely
+ * fragile until we cpu_idle() for the first time.
+ */
+ preempt_disable();
+ if (WARN(!irqs_disabled(),
+ "Interrupts were enabled *very* early, fixing it\n"))
+ local_irq_disable();
+ idr_init_cache();
+ rcu_init();
+
+ /* trace_printk() and trace points may be used after this */
+ trace_init();
+
+ context_tracking_init();
+ radix_tree_init();
+ /* init some links before init_ISA_irqs() */
+ early_irq_init();
+ init_IRQ();
+ tick_init();
+ rcu_init_nohz();
+ init_timers();
+ hrtimers_init();
+ softirq_init();
+ timekeeping_init();
+ time_init();
+ sched_clock_postinit();
+ perf_event_init();
+ profile_init();
+ call_function_init();
+ WARN(!irqs_disabled(), "Interrupts were enabled early\n");
+ early_boot_irqs_disabled = false;
+ local_irq_enable();
+
+ kmem_cache_init_late();
+
+ /*
+ * HACK ALERT! This is early. We're enabling the console before
+ * we've done PCI setups etc, and console_init() must be aware of
+ * this. But we do want output early, in case something goes wrong.
+ */
+ console_init();
+ if (panic_later)
+ panic("Too many boot %s vars at `%s'", panic_later,
+ panic_param);
+
+ lockdep_info();
+
+ /*
+ * Need to run this when irqs are enabled, because it wants
+ * to self-test [hard/soft]-irqs on/off lock inversion bugs
+ * too:
+ */
+ locking_selftest();
+
+#ifdef CONFIG_BLK_DEV_INITRD
+ if (initrd_start && !initrd_below_start_ok &&
+ page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
+ pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n",
+ page_to_pfn(virt_to_page((void *)initrd_start)),
+ min_low_pfn);
+ initrd_start = 0;
+ }
+#endif
+ page_ext_init();
+ debug_objects_mem_init();
+ kmemleak_init();
+ setup_per_cpu_pageset();
+ numa_policy_init();
+ if (late_time_init)
+ late_time_init();
+ sched_clock_init();
+ calibrate_delay();
+ pidmap_init();
+ anon_vma_init();
+ acpi_early_init();
+#ifdef CONFIG_X86
+ if (efi_enabled(EFI_RUNTIME_SERVICES))
+ efi_enter_virtual_mode();
+#endif
+#ifdef CONFIG_X86_ESPFIX64
+ /* Should be run before the first non-init thread is created */
+ init_espfix_bsp();
+#endif
+ thread_info_cache_init();
+ cred_init();
+ fork_init();
+ proc_caches_init();
+ buffer_init();
+ key_init();
+ security_init();
+ dbg_late_init();
+ vfs_caches_init(totalram_pages);
+ signals_init();
+ /* rootfs populating might need page-writeback */
+ page_writeback_init();
+ proc_root_init();
+ nsfs_init();
+ cpuset_init();
+ cgroup_init();
+ taskstats_init_early();
+ delayacct_init();
+
+ check_bugs();
+
+ acpi_subsystem_init();
+ sfi_init_late();
+
+ if (efi_enabled(EFI_RUNTIME_SERVICES)) {
+ efi_late_init();
+ efi_free_boot_services();
+ }
+
+ ftrace_init();
+
+ /* Do the rest non-__init'ed, we're now alive */
+ rest_init();
+}
+
+/* Call all constructor functions linked into the kernel. */
+static void __init do_ctors(void)
+{
+#ifdef CONFIG_CONSTRUCTORS
+ ctor_fn_t *fn = (ctor_fn_t *) __ctors_start;
+
+ for (; fn < (ctor_fn_t *) __ctors_end; fn++)
+ (*fn)();
+#endif
+}
+
+bool initcall_debug;
+core_param(initcall_debug, initcall_debug, bool, 0644);
+
+#ifdef CONFIG_KALLSYMS
+struct blacklist_entry {
+ struct list_head next;
+ char *buf;
+};
+
+static __initdata_or_module LIST_HEAD(blacklisted_initcalls);
+
+static int __init initcall_blacklist(char *str)
+{
+ char *str_entry;
+ struct blacklist_entry *entry;
+
+ /* str argument is a comma-separated list of functions */
+ do {
+ str_entry = strsep(&str, ",");
+ if (str_entry) {
+ pr_debug("blacklisting initcall %s\n", str_entry);
+ entry = alloc_bootmem(sizeof(*entry));
+ entry->buf = alloc_bootmem(strlen(str_entry) + 1);
+ strcpy(entry->buf, str_entry);
+ list_add(&entry->next, &blacklisted_initcalls);
+ }
+ } while (str_entry);
+
+ return 0;
+}
+
+static bool __init_or_module initcall_blacklisted(initcall_t fn)
+{
+ struct list_head *tmp;
+ struct blacklist_entry *entry;
+ char *fn_name;
+
+ fn_name = kasprintf(GFP_KERNEL, "%pf", fn);
+ if (!fn_name)
+ return false;
+
+ list_for_each(tmp, &blacklisted_initcalls) {
+ entry = list_entry(tmp, struct blacklist_entry, next);
+ if (!strcmp(fn_name, entry->buf)) {
+ pr_debug("initcall %s blacklisted\n", fn_name);
+ kfree(fn_name);
+ return true;
+ }
+ }
+
+ kfree(fn_name);
+ return false;
+}
+#else
+static int __init initcall_blacklist(char *str)
+{
+ pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n");
+ return 0;
+}
+
+static bool __init_or_module initcall_blacklisted(initcall_t fn)
+{
+ return false;
+}
+#endif
+__setup("initcall_blacklist=", initcall_blacklist);
+
+static int __init_or_module do_one_initcall_debug(initcall_t fn)
+{
+ ktime_t calltime, delta, rettime;
+ unsigned long long duration;
+ int ret;
+
+ printk(KERN_DEBUG "calling %pF @ %i\n", fn, task_pid_nr(current));
+ calltime = ktime_get();
+ ret = fn();
+ rettime = ktime_get();
+ delta = ktime_sub(rettime, calltime);
+ duration = (unsigned long long) ktime_to_ns(delta) >> 10;
+ printk(KERN_DEBUG "initcall %pF returned %d after %lld usecs\n",
+ fn, ret, duration);
+
+ return ret;
+}
+
+int __init_or_module do_one_initcall(initcall_t fn)
+{
+ int count = preempt_count();
+ int ret;
+ char msgbuf[64];
+
+ if (initcall_blacklisted(fn))
+ return -EPERM;
+
+ if (initcall_debug)
+ ret = do_one_initcall_debug(fn);
+ else
+ ret = fn();
+
+ msgbuf[0] = 0;
+
+ if (preempt_count() != count) {
+ sprintf(msgbuf, "preemption imbalance ");
+ preempt_count_set(count);
+ }
+ if (irqs_disabled()) {
+ strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf));
+ local_irq_enable();
+ }
+ WARN(msgbuf[0], "initcall %pF returned with %s\n", fn, msgbuf);
+
+ return ret;
+}
+
+
+extern initcall_t __initcall_start[];
+extern initcall_t __initcall0_start[];
+extern initcall_t __initcall1_start[];
+extern initcall_t __initcall2_start[];
+extern initcall_t __initcall3_start[];
+extern initcall_t __initcall4_start[];
+extern initcall_t __initcall5_start[];
+extern initcall_t __initcall6_start[];
+extern initcall_t __initcall7_start[];
+extern initcall_t __initcall_end[];
+
+static initcall_t *initcall_levels[] __initdata = {
+ __initcall0_start,
+ __initcall1_start,
+ __initcall2_start,
+ __initcall3_start,
+ __initcall4_start,
+ __initcall5_start,
+ __initcall6_start,
+ __initcall7_start,
+ __initcall_end,
+};
+
+/* Keep these in sync with initcalls in include/linux/init.h */
+static char *initcall_level_names[] __initdata = {
+ "early",
+ "core",
+ "postcore",
+ "arch",
+ "subsys",
+ "fs",
+ "device",
+ "late",
+};
+
+static void __init do_initcall_level(int level)
+{
+ initcall_t *fn;
+
+ strcpy(initcall_command_line, saved_command_line);
+ parse_args(initcall_level_names[level],
+ initcall_command_line, __start___param,
+ __stop___param - __start___param,
+ level, level,
+ &repair_env_string);
+
+ for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++)
+ do_one_initcall(*fn);
+}
+
+static void __init do_initcalls(void)
+{
+ int level;
+
+ for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++)
+ do_initcall_level(level);
+}
+
+/*
+ * Ok, the machine is now initialized. None of the devices
+ * have been touched yet, but the CPU subsystem is up and
+ * running, and memory and process management works.
+ *
+ * Now we can finally start doing some real work..
+ */
+static void __init do_basic_setup(void)
+{
+ cpuset_init_smp();
+ usermodehelper_init();
+ shmem_init();
+ driver_init();
+ init_irq_proc();
+ do_ctors();
+ usermodehelper_enable();
+ do_initcalls();
+ random_int_secret_init();
+}
+
+static void __init do_pre_smp_initcalls(void)
+{
+ initcall_t *fn;
+
+ for (fn = __initcall_start; fn < __initcall0_start; fn++)
+ do_one_initcall(*fn);
+}
+
+/*
+ * This function requests modules which should be loaded by default and is
+ * called twice right after initrd is mounted and right before init is
+ * exec'd. If such modules are on either initrd or rootfs, they will be
+ * loaded before control is passed to userland.
+ */
+void __init load_default_modules(void)
+{
+ load_default_elevator_module();
+}
+
+static int run_init_process(const char *init_filename)
+{
+ argv_init[0] = init_filename;
+ return do_execve(getname_kernel(init_filename),
+ (const char __user *const __user *)argv_init,
+ (const char __user *const __user *)envp_init);
+}
+
+static int try_to_run_init_process(const char *init_filename)
+{
+ int ret;
+
+ ret = run_init_process(init_filename);
+
+ if (ret && ret != -ENOENT) {
+ pr_err("Starting init: %s exists but couldn't execute it (error %d)\n",
+ init_filename, ret);
+ }
+
+ return ret;
+}
+
+static noinline void __init kernel_init_freeable(void);
+
+static int __ref kernel_init(void *unused)
+{
+ int ret;
+
+ kernel_init_freeable();
+ /* need to finish all async __init code before freeing the memory */
+ async_synchronize_full();
+ free_initmem();
+ mark_rodata_ro();
+ system_state = SYSTEM_RUNNING;
+ numa_default_policy();
+
+ flush_delayed_fput();
+
+ if (ramdisk_execute_command) {
+ ret = run_init_process(ramdisk_execute_command);
+ if (!ret)
+ return 0;
+ pr_err("Failed to execute %s (error %d)\n",
+ ramdisk_execute_command, ret);
+ }
+
+ /*
+ * We try each of these until one succeeds.
+ *
+ * The Bourne shell can be used instead of init if we are
+ * trying to recover a really broken machine.
+ */
+ if (execute_command) {
+ ret = run_init_process(execute_command);
+ if (!ret)
+ return 0;
+ panic("Requested init %s failed (error %d).",
+ execute_command, ret);
+ }
+ if (!try_to_run_init_process("/sbin/init") ||
+ !try_to_run_init_process("/etc/init") ||
+ !try_to_run_init_process("/bin/init") ||
+ !try_to_run_init_process("/bin/sh"))
+ return 0;
+
+ panic("No working init found. Try passing init= option to kernel. "
+ "See Linux Documentation/init.txt for guidance.");
+}
+
+static noinline void __init kernel_init_freeable(void)
+{
+ /*
+ * Wait until kthreadd is all set-up.
+ */
+ wait_for_completion(&kthreadd_done);
+
+ /* Now the scheduler is fully set up and can do blocking allocations */
+ gfp_allowed_mask = __GFP_BITS_MASK;
+
+ /*
+ * init can allocate pages on any node
+ */
+ set_mems_allowed(node_states[N_MEMORY]);
+ /*
+ * init can run on any cpu.
+ */
+ set_cpus_allowed_ptr(current, cpu_all_mask);
+
+ cad_pid = task_pid(current);
+
+ smp_prepare_cpus(setup_max_cpus);
+
+ do_pre_smp_initcalls();
+ lockup_detector_init();
+
+ smp_init();
+ sched_init_smp();
+
+ do_basic_setup();
+
+ /* Open the /dev/console on the rootfs, this should never fail */
+ if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
+ pr_err("Warning: unable to open an initial console.\n");
+
+ (void) sys_dup(0);
+ (void) sys_dup(0);
+ /*
+ * check if there is an early userspace init. If yes, let it do all
+ * the work
+ */
+
+ if (!ramdisk_execute_command)
+ ramdisk_execute_command = "/init";
+
+ if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
+ ramdisk_execute_command = NULL;
+ prepare_namespace();
+ }
+
+ /*
+ * Ok, we have completed the initial bootup, and
+ * we're essentially up and running. Get rid of the
+ * initmem segments and start the user-mode stuff..
+ *
+ * rootfs is available now, try loading the public keys
+ * and default modules
+ */
+
+ integrity_load_keys();
+ load_default_modules();
+}