* Simplified starting of init: Michael A. Griffith <grif@acm.org>
*/
-#define __KERNEL_SYSCALLS__
-
-#include <linux/config.h>
#include <linux/types.h>
#include <linux/module.h>
#include <linux/proc_fs.h>
-#include <linux/devfs_fs_kernel.h>
#include <linux/kernel.h>
#include <linux/syscalls.h>
#include <linux/string.h>
#include <linux/percpu.h>
#include <linux/kmod.h>
#include <linux/kernel_stat.h>
+#include <linux/start_kernel.h>
#include <linux/security.h>
#include <linux/workqueue.h>
#include <linux/profile.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/unwind.h>
+#include <linux/buffer_head.h>
+#include <linux/debug_locks.h>
+#include <linux/lockdep.h>
+#include <linux/pid_namespace.h>
+#include <linux/device.h>
+#include <linux/kthread.h>
+#include <linux/sched.h>
#include <asm/io.h>
#include <asm/bugs.h>
#include <asm/setup.h>
#include <asm/sections.h>
-
-/*
- * This is one of the first .c files built. Error out early
- * if we have compiler trouble..
- */
-#if __GNUC__ == 2 && __GNUC_MINOR__ == 96
-#ifdef CONFIG_FRAME_POINTER
-#error This compiler cannot compile correctly with frame pointers enabled
-#endif
-#endif
+#include <asm/cacheflush.h>
#ifdef CONFIG_X86_LOCAL_APIC
#include <asm/smp.h>
#endif
/*
- * Versions of gcc older than that listed below may actually compile
- * and link okay, but the end product can have subtle run time bugs.
- * To avoid associated bogus bug reports, we flatly refuse to compile
- * with a gcc that is known to be too old from the very beginning.
+ * This is one of the first .c files built. Error out early if we have compiler
+ * trouble.
*/
-#if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 95)
-#error Sorry, your GCC is too old. It builds incorrect kernels.
+
+#if __GNUC__ == 4 && __GNUC_MINOR__ == 1 && __GNUC_PATCHLEVEL__ == 0
+#warning gcc-4.1.0 is known to miscompile the kernel. A different compiler version is recommended.
#endif
-static int init(void *);
+static int kernel_init(void *);
extern void init_IRQ(void);
-extern void sock_init(void);
extern void fork_init(unsigned long);
extern void mca_init(void);
extern void sbus_init(void);
-extern void sysctl_init(void);
extern void signals_init(void);
-extern void buffer_init(void);
extern void pidhash_init(void);
extern void pidmap_init(void);
extern void prio_tree_init(void);
extern void radix_tree_init(void);
extern void free_initmem(void);
-extern void populate_rootfs(void);
-extern void driver_init(void);
-extern void prepare_namespace(void);
#ifdef CONFIG_ACPI
extern void acpi_early_init(void);
#else
static inline void acpi_early_init(void) { }
#endif
+#ifndef CONFIG_DEBUG_RODATA
+static inline void mark_rodata_ro(void) { }
+#endif
#ifdef CONFIG_TC
extern void tc_init(void);
void (*late_time_init)(void);
extern void softirq_init(void);
-/* Untouched command line (eg. for /proc) saved by arch-specific code. */
-char saved_command_line[COMMAND_LINE_SIZE];
+/* 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;
static char *execute_command;
+static char *ramdisk_execute_command;
+#ifdef CONFIG_SMP
/* Setup configured maximum number of CPUs to activate */
-static unsigned int max_cpus = NR_CPUS;
+unsigned int __initdata setup_max_cpus = NR_CPUS;
/*
* Setup routine for controlling SMP activation
* greater than 0, limits the maximum number of CPUs activated in
* SMP mode to <NUM>.
*/
+#ifndef CONFIG_X86_IO_APIC
+static inline void disable_ioapic_setup(void) {};
+#endif
+
static int __init nosmp(char *str)
{
- max_cpus = 0;
- return 1;
+ setup_max_cpus = 0;
+ disable_ioapic_setup();
+ return 0;
}
-__setup("nosmp", nosmp);
+early_param("nosmp", nosmp);
static int __init maxcpus(char *str)
{
- get_option(&str, &max_cpus);
+ get_option(&str, &setup_max_cpus);
+ if (setup_max_cpus == 0)
+ disable_ioapic_setup();
+
+ return 0;
+}
+
+early_param("maxcpus", maxcpus);
+#else
+#define setup_max_cpus NR_CPUS
+#endif
+
+/*
+ * 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 situaiton 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("maxcpus=", maxcpus);
+__setup("reset_devices", set_reset_devices);
static char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
static int __init obsolete_checksetup(char *line)
{
struct obs_kernel_param *p;
+ int had_early_param = 0;
p = __setup_start;
do {
int n = strlen(p->str);
if (!strncmp(line, p->str, n)) {
if (p->early) {
- /* Already done in parse_early_param? (Needs
- * exact match on param part) */
+ /* 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] == '=')
- return 1;
+ had_early_param = 1;
} else if (!p->setup_func) {
printk(KERN_WARNING "Parameter %s is obsolete,"
" ignored\n", p->str);
}
p++;
} while (p < __setup_end);
- return 0;
+
+ return had_early_param;
}
/*
return 0;
/*
- * Preemptive maintenance for "why didn't my mispelled command
+ * Preemptive maintenance for "why didn't my misspelled command
* line work?"
*/
if (strchr(param, '.') && (!val || strchr(param, '.') < val)) {
return 0;
}
+#ifdef CONFIG_DEBUG_PAGEALLOC
+int __read_mostly debug_pagealloc_enabled = 0;
+#endif
+
static int __init init_setup(char *str)
{
unsigned int i;
}
__setup("init=", init_setup);
-extern void setup_arch(char **);
+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
#else
-#ifdef __GENERIC_PER_CPU
-unsigned long __per_cpu_offset[NR_CPUS];
+#ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
+unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
EXPORT_SYMBOL(__per_cpu_offset);
{
unsigned long size, i;
char *ptr;
+ unsigned long nr_possible_cpus = num_possible_cpus();
/* Copy section for each CPU (we discard the original) */
- size = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES);
-#ifdef CONFIG_MODULES
- if (size < PERCPU_ENOUGH_ROOM)
- size = PERCPU_ENOUGH_ROOM;
-#endif
+ size = ALIGN(PERCPU_ENOUGH_ROOM, PAGE_SIZE);
+ ptr = alloc_bootmem_pages(size * nr_possible_cpus);
- ptr = alloc_bootmem(size * NR_CPUS);
-
- for (i = 0; i < NR_CPUS; i++, ptr += size) {
+ for_each_possible_cpu(i) {
__per_cpu_offset[i] = ptr - __per_cpu_start;
memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
+ ptr += size;
}
}
-#endif /* !__GENERIC_PER_CPU */
+#endif /* CONFIG_HAVE_SETUP_PER_CPU_AREA */
/* Called by boot processor to activate the rest. */
static void __init smp_init(void)
{
- unsigned int i;
+ unsigned int cpu;
/* FIXME: This should be done in userspace --RR */
- for_each_present_cpu(i) {
- if (num_online_cpus() >= max_cpus)
+ for_each_present_cpu(cpu) {
+ if (num_online_cpus() >= setup_max_cpus)
break;
- if (!cpu_online(i))
- cpu_up(i);
+ if (!cpu_online(cpu))
+ cpu_up(cpu);
}
/* Any cleanup work */
printk(KERN_INFO "Brought up %ld CPUs\n", (long)num_online_cpus());
- smp_cpus_done(max_cpus);
-#if 0
- /* Get other processors into their bootup holding patterns. */
-
- smp_commence();
-#endif
+ smp_cpus_done(setup_max_cpus);
}
#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 = alloc_bootmem(strlen (boot_command_line)+1);
+ static_command_line = alloc_bootmem(strlen (command_line)+1);
+ 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
* gcc-3.4 accidentally inlines this function, so use noinline.
*/
-static void noinline rest_init(void)
+static void noinline __init_refok rest_init(void)
__releases(kernel_lock)
{
- kernel_thread(init, NULL, CLONE_FS | CLONE_SIGHAND);
+ int pid;
+
+ kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND);
numa_default_policy();
+ pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
+ kthreadd_task = find_task_by_pid(pid);
unlock_kernel();
- preempt_enable_no_resched();
/*
* The boot idle thread must execute schedule()
- * at least one to get things moving:
+ * at least once to get things moving:
*/
+ init_idle_bootup_task(current);
+ preempt_enable_no_resched();
schedule();
+ preempt_disable();
+ /* Call into cpu_idle with preempt disabled */
cpu_idle();
-}
+}
/* Check for early params. */
static int __init do_early_param(char *param, char *val)
struct obs_kernel_param *p;
for (p = __setup_start; p < __setup_end; p++) {
- if (p->early && strcmp(param, p->str) == 0) {
+ if ((p->early && strcmp(param, p->str) == 0) ||
+ (strcmp(param, "console") == 0 &&
+ strcmp(p->str, "earlycon") == 0)
+ ) {
if (p->setup_func(val) != 0)
printk(KERN_WARNING
"Malformed early option '%s'\n", param);
return;
/* All fall through to do_early_param. */
- strlcpy(tmp_cmdline, saved_command_line, COMMAND_LINE_SIZE);
+ strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
parse_args("early options", tmp_cmdline, NULL, 0, do_early_param);
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 */
+ cpu_set(cpu, cpu_online_map);
+ cpu_set(cpu, cpu_present_map);
+ cpu_set(cpu, cpu_possible_map);
+}
+
+void __init __attribute__((weak)) smp_setup_processor_id(void)
+{
+}
+
asmlinkage void __init start_kernel(void)
{
char * command_line;
extern struct kernel_param __start___param[], __stop___param[];
+
+ smp_setup_processor_id();
+
+ /*
+ * Need to run as early as possible, to initialize the
+ * lockdep hash:
+ */
+ unwind_init();
+ lockdep_init();
+ cgroup_init_early();
+
+ local_irq_disable();
+ early_boot_irqs_off();
+ early_init_irq_lock_class();
+
/*
* Interrupts are still disabled. Do necessary setups, then
* enable them
*/
lock_kernel();
+ tick_init();
+ boot_cpu_init();
page_address_init();
printk(KERN_NOTICE);
printk(linux_banner);
setup_arch(&command_line);
+ setup_command_line(command_line);
+ unwind_setup();
setup_per_cpu_areas();
-
- /*
- * Mark the boot cpu "online" so that it can call console drivers in
- * printk() and can access its per-cpu storage.
- */
- smp_prepare_boot_cpu();
+ smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
/*
* Set up the scheduler prior starting any interrupts (such as the
preempt_disable();
build_all_zonelists();
page_alloc_init();
- printk(KERN_NOTICE "Kernel command line: %s\n", saved_command_line);
+ enable_debug_pagealloc();
+ printk(KERN_NOTICE "Kernel command line: %s\n", boot_command_line);
parse_early_param();
- parse_args("Booting kernel", command_line, __start___param,
+ parse_args("Booting kernel", static_command_line, __start___param,
__stop___param - __start___param,
&unknown_bootoption);
+ if (!irqs_disabled()) {
+ printk(KERN_WARNING "start_kernel(): bug: interrupts were "
+ "enabled *very* early, fixing it\n");
+ local_irq_disable();
+ }
sort_main_extable();
trap_init();
rcu_init();
init_IRQ();
pidhash_init();
init_timers();
+ hrtimers_init();
softirq_init();
+ timekeeping_init();
time_init();
+ profile_init();
+ if (!irqs_disabled())
+ printk("start_kernel(): bug: interrupts were enabled early\n");
+ early_boot_irqs_on();
+ local_irq_enable();
/*
* HACK ALERT! This is early. We're enabling the console before
console_init();
if (panic_later)
panic(panic_later, panic_param);
- profile_init();
- local_irq_enable();
+
+ 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 &&
initrd_start < min_low_pfn << PAGE_SHIFT) {
}
#endif
vfs_caches_init_early();
+ cpuset_init_early();
mem_init();
+ cpu_hotplug_init();
kmem_cache_init();
setup_per_cpu_pageset();
numa_policy_init();
#ifdef CONFIG_PROC_FS
proc_root_init();
#endif
+ cgroup_init();
cpuset_init();
+ taskstats_init_early();
+ delayacct_init();
check_bugs();
}
__setup("initcall_debug", initcall_debug_setup);
-struct task_struct *child_reaper = &init_task;
-
extern initcall_t __initcall_start[], __initcall_end[];
static void __init do_initcalls(void)
int count = preempt_count();
for (call = __initcall_start; call < __initcall_end; call++) {
- char *msg;
+ ktime_t t0, t1, delta;
+ char *msg = NULL;
+ char msgbuf[40];
+ int result;
if (initcall_debug) {
- printk(KERN_DEBUG "Calling initcall 0x%p", *call);
- print_fn_descriptor_symbol(": %s()", (unsigned long) *call);
+ printk("Calling initcall 0x%p", *call);
+ print_fn_descriptor_symbol(": %s()",
+ (unsigned long) *call);
printk("\n");
+ t0 = ktime_get();
}
- (*call)();
+ result = (*call)();
+
+ if (initcall_debug) {
+ t1 = ktime_get();
+ delta = ktime_sub(t1, t0);
+
+ printk("initcall 0x%p", *call);
+ print_fn_descriptor_symbol(": %s()",
+ (unsigned long) *call);
+ printk(" returned %d.\n", result);
+
+ printk("initcall 0x%p ran for %Ld msecs: ",
+ *call, (unsigned long long)delta.tv64 >> 20);
+ print_fn_descriptor_symbol("%s()\n",
+ (unsigned long) *call);
+ }
- msg = NULL;
+ if (result && result != -ENODEV && initcall_debug) {
+ sprintf(msgbuf, "error code %d", result);
+ msg = msgbuf;
+ }
if (preempt_count() != count) {
msg = "preemption imbalance";
preempt_count() = count;
local_irq_enable();
}
if (msg) {
- printk(KERN_WARNING "error in initcall at 0x%p: "
- "returned with %s\n", *call, msg);
+ printk(KERN_WARNING "initcall at 0x%p", *call);
+ print_fn_descriptor_symbol(": %s()",
+ (unsigned long) *call);
+ printk(": returned with %s\n", msg);
}
}
init_workqueues();
usermodehelper_init();
driver_init();
+ init_irq_proc();
+ do_initcalls();
+}
-#ifdef CONFIG_SYSCTL
- sysctl_init();
-#endif
-
- /* Networking initialization needs a process context */
- sock_init();
+static int __initdata nosoftlockup;
- do_initcalls();
+static int __init nosoftlockup_setup(char *str)
+{
+ nosoftlockup = 1;
+ return 1;
}
+__setup("nosoftlockup", nosoftlockup_setup);
-static void do_pre_smp_initcalls(void)
+static void __init do_pre_smp_initcalls(void)
{
extern int spawn_ksoftirqd(void);
-#ifdef CONFIG_SMP
- extern int migration_init(void);
migration_init();
-#endif
spawn_ksoftirqd();
+ if (!nosoftlockup)
+ spawn_softlockup_task();
}
static void run_init_process(char *init_filename)
{
argv_init[0] = init_filename;
- execve(init_filename, argv_init, envp_init);
+ kernel_execve(init_filename, argv_init, envp_init);
}
-static inline void fixup_cpu_present_map(void)
+/* This is a non __init function. Force it to be noinline otherwise gcc
+ * makes it inline to init() and it becomes part of init.text section
+ */
+static int noinline init_post(void)
{
-#ifdef CONFIG_SMP
- int i;
+ free_initmem();
+ unlock_kernel();
+ mark_rodata_ro();
+ system_state = SYSTEM_RUNNING;
+ numa_default_policy();
+
+ if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
+ printk(KERN_WARNING "Warning: unable to open an initial console.\n");
+
+ (void) sys_dup(0);
+ (void) sys_dup(0);
+
+ if (ramdisk_execute_command) {
+ run_init_process(ramdisk_execute_command);
+ printk(KERN_WARNING "Failed to execute %s\n",
+ ramdisk_execute_command);
+ }
/*
- * If arch is not hotplug ready and did not populate
- * cpu_present_map, just make cpu_present_map same as cpu_possible_map
- * for other cpu bringup code to function as normal. e.g smp_init() etc.
+ * 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 (cpus_empty(cpu_present_map)) {
- for_each_cpu(i) {
- cpu_set(i, cpu_present_map);
- }
+ if (execute_command) {
+ run_init_process(execute_command);
+ printk(KERN_WARNING "Failed to execute %s. Attempting "
+ "defaults...\n", execute_command);
}
-#endif
+ run_init_process("/sbin/init");
+ run_init_process("/etc/init");
+ run_init_process("/bin/init");
+ run_init_process("/bin/sh");
+
+ panic("No init found. Try passing init= option to kernel.");
}
-static int init(void * unused)
+static int __init kernel_init(void * unused)
{
lock_kernel();
/*
* assumptions about where in the task array this
* can be found.
*/
- child_reaper = current;
+ init_pid_ns.child_reaper = current;
- /* Sets up cpus_possible() */
- smp_prepare_cpus(max_cpus);
+ __set_special_pids(1, 1);
+ cad_pid = task_pid(current);
+
+ smp_prepare_cpus(setup_max_cpus);
do_pre_smp_initcalls();
- fixup_cpu_present_map();
smp_init();
sched_init_smp();
cpuset_init_smp();
- /*
- * Do this before initcalls, because some drivers want to access
- * firmware files.
- */
- populate_rootfs();
-
do_basic_setup();
/*
* check if there is an early userspace init. If yes, let it do all
* the work
*/
- if (sys_access((const char __user *) "/init", 0) == 0)
- execute_command = "/init";
- else
+
+ 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..
*/
- free_initmem();
- unlock_kernel();
- system_state = SYSTEM_RUNNING;
- numa_default_policy();
-
- if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
- printk(KERN_WARNING "Warning: unable to open an initial console.\n");
-
- (void) sys_dup(0);
- (void) sys_dup(0);
-
- /*
- * 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)
- run_init_process(execute_command);
-
- run_init_process("/sbin/init");
- run_init_process("/etc/init");
- run_init_process("/bin/init");
- run_init_process("/bin/sh");
-
- panic("No init found. Try passing init= option to kernel.");
+ init_post();
+ return 0;
}