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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  *  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/extable.h>
 #include <linux/module.h>
 #include <linux/proc_fs.h>
 #include <linux/binfmts.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/memblock.h>
 #include <linux/acpi.h>
 #include <linux/bootconfig.h>
 #include <linux/console.h>
 #include <linux/nmi.h>
 #include <linux/percpu.h>
 #include <linux/kmod.h>
 #include <linux/kprobes.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/kfence.h>
 #include <linux/rcupdate.h>
 #include <linux/srcu.h>
 #include <linux/moduleparam.h>
 #include <linux/kallsyms.h>
 #include <linux/buildid.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/sched/isolation.h>
 #include <linux/interrupt.h>
 #include <linux/taskstats_kern.h>
 #include <linux/delayacct.h>
 #include <linux/unistd.h>
 #include <linux/utsname.h>
 #include <linux/rmap.h>
 #include <linux/mempolicy.h>
 #include <linux/key.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/padata.h>
 #include <linux/pid_namespace.h>
 #include <linux/device/driver.h>
 #include <linux/kthread.h>
 #include <linux/sched.h>
 #include <linux/sched/init.h>
 #include <linux/signal.h>
 #include <linux/idr.h>
 #include <linux/kgdb.h>
 #include <linux/ftrace.h>
 #include <linux/async.h>
 #include <linux/shmem_fs.h>
 #include <linux/slab.h>
 #include <linux/perf_event.h>
 #include <linux/ptrace.h>
 #include <linux/pti.h>
 #include <linux/blkdev.h>
 #include <linux/sched/clock.h>
 #include <linux/sched/task.h>
 #include <linux/sched/task_stack.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 <linux/cache.h>
 #include <linux/rodata_test.h>
 #include <linux/jump_label.h>
 #include <linux/mem_encrypt.h>
 #include <linux/kcsan.h>
 #include <linux/init_syscalls.h>
 #include <linux/stackdepot.h>
 #include <linux/randomize_kstack.h>
 #include <net/net_namespace.h>
 
 #include <asm/io.h>
 #include <asm/bugs.h>
 #include <asm/setup.h>
 #include <asm/sections.h>
 #include <asm/cacheflush.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/initcall.h>
 
 #include <kunit/test.h>
 
 static int kernel_init(void *);
 
 extern void init_IRQ(void);
 extern void radix_tree_init(void);
 
 /*
  * 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;
 /* Untouched extra command line */
 static char *extra_command_line;
 /* Extra init arguments */
 static char *extra_init_args;
 
 #ifdef CONFIG_BOOT_CONFIG
 /* Is bootconfig on command line? */
 static bool bootconfig_found;
 static size_t initargs_offs;
 #else
 # define bootconfig_found false
 # define initargs_offs 0
 #endif
 
 static char *execute_command;
 static char *ramdisk_execute_command = "/init";
 
 /*
  * 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 bool __init obsolete_checksetup(char *line)
 {
     const struct obs_kernel_param *p;
     bool had_early_param = false;
 
     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 = true;
             } else if (!p->setup_func) {
                 pr_warn("Parameter %s is obsolete, ignored\n",
                     p->str);
                 return true;
             } else if (p->setup_func(line + n))
                 return true;
         }
         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);
 
 #ifdef CONFIG_BLK_DEV_INITRD
 static void * __init get_boot_config_from_initrd(size_t *_size)
 {
     u32 size, csum;
     char *data;
     u32 *hdr;
     int i;
 
     if (!initrd_end)
         return NULL;
 
     data = (char *)initrd_end - BOOTCONFIG_MAGIC_LEN;
     /*
      * Since Grub may align the size of initrd to 4, we must
      * check the preceding 3 bytes as well.
      */
     for (i = 0; i < 4; i++) {
         if (!memcmp(data, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN))
             goto found;
         data--;
     }
     return NULL;
 
 found:
     hdr = (u32 *)(data - 8);
     size = le32_to_cpu(hdr[0]);
     csum = le32_to_cpu(hdr[1]);
 
     data = ((void *)hdr) - size;
     if ((unsigned long)data < initrd_start) {
         pr_err("bootconfig size %d is greater than initrd size %ld\n",
             size, initrd_end - initrd_start);
         return NULL;
     }
 
     if (xbc_calc_checksum(data, size) != csum) {
         pr_err("bootconfig checksum failed\n");
         return NULL;
     }
 
     /* Remove bootconfig from initramfs/initrd */
     initrd_end = (unsigned long)data;
     if (_size)
         *_size = size;
 
     return data;
 }
 #else
 static void * __init get_boot_config_from_initrd(size_t *_size)
 {
     return NULL;
 }
 #endif
 
 #ifdef CONFIG_BOOT_CONFIG
 
 static char xbc_namebuf[XBC_KEYLEN_MAX] __initdata;
 
 #define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0)
 
 static int __init xbc_snprint_cmdline(char *buf, size_t size,
                       struct xbc_node *root)
 {
     struct xbc_node *knode, *vnode;
     char *end = buf + size;
     const char *val;
     int ret;
 
     xbc_node_for_each_key_value(root, knode, val) {
         ret = xbc_node_compose_key_after(root, knode,
                     xbc_namebuf, XBC_KEYLEN_MAX);
         if (ret < 0)
             return ret;
 
         vnode = xbc_node_get_child(knode);
         if (!vnode) {
             ret = snprintf(buf, rest(buf, end), "%s ", xbc_namebuf);
             if (ret < 0)
                 return ret;
             buf += ret;
             continue;
         }
         xbc_array_for_each_value(vnode, val) {
             ret = snprintf(buf, rest(buf, end), "%s=\"%s\" ",
                        xbc_namebuf, val);
             if (ret < 0)
                 return ret;
             buf += ret;
         }
     }
 
     return buf - (end - size);
 }
 #undef rest
 
 /* Make an extra command line under given key word */
 static char * __init xbc_make_cmdline(const char *key)
 {
     struct xbc_node *root;
     char *new_cmdline;
     int ret, len = 0;
 
     root = xbc_find_node(key);
     if (!root)
         return NULL;
 
     /* Count required buffer size */
     len = xbc_snprint_cmdline(NULL, 0, root);
     if (len <= 0)
         return NULL;
 
     new_cmdline = memblock_alloc(len + 1, SMP_CACHE_BYTES);
     if (!new_cmdline) {
         pr_err("Failed to allocate memory for extra kernel cmdline.\n");
         return NULL;
     }
 
     ret = xbc_snprint_cmdline(new_cmdline, len + 1, root);
     if (ret < 0 || ret > len) {
         pr_err("Failed to print extra kernel cmdline.\n");
         memblock_free(new_cmdline, len + 1);
         return NULL;
     }
 
     return new_cmdline;
 }
 
 static int __init bootconfig_params(char *param, char *val,
                     const char *unused, void *arg)
 {
     if (strcmp(param, "bootconfig") == 0) {
         bootconfig_found = true;
     }
     return 0;
 }
 
 static int __init warn_bootconfig(char *str)
 {
     /* The 'bootconfig' has been handled by bootconfig_params(). */
     return 0;
 }
 
 static void __init setup_boot_config(void)
 {
     static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata;
     const char *msg, *data;
     int pos, ret;
     size_t size;
     char *err;
 
     /* Cut out the bootconfig data even if we have no bootconfig option */
     data = get_boot_config_from_initrd(&size);
     /* If there is no bootconfig in initrd, try embedded one. */
     if (!data)
         data = xbc_get_embedded_bootconfig(&size);
 
     strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
     err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL,
              bootconfig_params);
 
     if (IS_ERR(err) || !bootconfig_found)
         return;
 
     /* parse_args() stops at the next param of '--' and returns an address */
     if (err)
         initargs_offs = err - tmp_cmdline;
 
     if (!data) {
         pr_err("'bootconfig' found on command line, but no bootconfig found\n");
         return;
     }
 
     if (size >= XBC_DATA_MAX) {
         pr_err("bootconfig size %ld greater than max size %d\n",
             (long)size, XBC_DATA_MAX);
         return;
     }
 
     ret = xbc_init(data, size, &msg, &pos);
     if (ret < 0) {
         if (pos < 0)
             pr_err("Failed to init bootconfig: %s.\n", msg);
         else
             pr_err("Failed to parse bootconfig: %s at %d.\n",
                 msg, pos);
     } else {
         xbc_get_info(&ret, NULL);
         pr_info("Load bootconfig: %ld bytes %d nodes\n", (long)size, ret);
         /* keys starting with "kernel." are passed via cmdline */
         extra_command_line = xbc_make_cmdline("kernel");
         /* Also, "init." keys are init arguments */
         extra_init_args = xbc_make_cmdline("init");
     }
     return;
 }
 
 static void __init exit_boot_config(void)
 {
     xbc_exit();
 }
 
 #else   /* !CONFIG_BOOT_CONFIG */
 
 static void __init setup_boot_config(void)
 {
     /* Remove bootconfig data from initrd */
     get_boot_config_from_initrd(NULL);
 }
 
 static int __init warn_bootconfig(char *str)
 {
     pr_warn("WARNING: 'bootconfig' found on the kernel command line but CONFIG_BOOT_CONFIG is not set.\n");
     return 0;
 }
 
 #define exit_boot_config()  do {} while (0)
 
 #endif  /* CONFIG_BOOT_CONFIG */
 
 early_param("bootconfig", warn_bootconfig);
 
 /* Change NUL term back to "=", to make "param" the whole string. */
 static void __init repair_env_string(char *param, char *val)
 {
     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);
         } else
             BUG();
     }
 }
 
 /* Anything after -- gets handed straight to init. */
 static int __init set_init_arg(char *param, char *val,
                    const char *unused, void *arg)
 {
     unsigned int i;
 
     if (panic_later)
         return 0;
 
     repair_env_string(param, val);
 
     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, void *arg)
 {
     size_t len = strlen(param);
 
     repair_env_string(param, val);
 
     /* Handle obsolete-style parameters */
     if (obsolete_checksetup(param))
         return 0;
 
     /* Unused module parameter. */
     if (strnchr(param, len, '.'))
         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], len+1))
                 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)
 {
     size_t len, xlen = 0, ilen = 0;
 
     if (extra_command_line)
         xlen = strlen(extra_command_line);
     if (extra_init_args)
         ilen = strlen(extra_init_args) + 4; /* for " -- " */
 
     len = xlen + strlen(boot_command_line) + 1;
 
     saved_command_line = memblock_alloc(len + ilen, SMP_CACHE_BYTES);
     if (!saved_command_line)
         panic("%s: Failed to allocate %zu bytes\n", __func__, len + ilen);
 
     static_command_line = memblock_alloc(len, SMP_CACHE_BYTES);
     if (!static_command_line)
         panic("%s: Failed to allocate %zu bytes\n", __func__, len);
 
     if (xlen) {
         /*
          * We have to put extra_command_line before boot command
          * lines because there could be dashes (separator of init
          * command line) in the command lines.
          */
         strcpy(saved_command_line, extra_command_line);
         strcpy(static_command_line, extra_command_line);
     }
     strcpy(saved_command_line + xlen, boot_command_line);
     strcpy(static_command_line + xlen, command_line);
 
     if (ilen) {
         /*
          * Append supplemental init boot args to saved_command_line
          * so that user can check what command line options passed
          * to init.
          * The order should always be
          * " -- "[bootconfig init-param][cmdline init-param]
          */
         if (initargs_offs) {
             len = xlen + initargs_offs;
             strcpy(saved_command_line + len, extra_init_args);
             len += ilen - 4;    /* strlen(extra_init_args) */
             strcpy(saved_command_line + len,
                 boot_command_line + initargs_offs - 1);
         } else {
             len = strlen(saved_command_line);
             strcpy(saved_command_line + len, " -- ");
             len += 4;
             strcpy(saved_command_line + len, extra_init_args);
         }
     }
 }
 
 /*
  * 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);
 
 noinline void __ref rest_init(void)
 {
     struct task_struct *tsk;
     int pid;
 
     rcu_scheduler_starting();
     /*
      * 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.
      */
     pid = user_mode_thread(kernel_init, NULL, CLONE_FS);
     /*
      * Pin init on the boot CPU. Task migration is not properly working
      * until sched_init_smp() has been run. It will set the allowed
      * CPUs for init to the non isolated CPUs.
      */
     rcu_read_lock();
     tsk = find_task_by_pid_ns(pid, &init_pid_ns);
     tsk->flags |= PF_NO_SETAFFINITY;
     set_cpus_allowed_ptr(tsk, cpumask_of(smp_processor_id()));
     rcu_read_unlock();
 
     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();
 
     /*
      * Enable might_sleep() and smp_processor_id() checks.
      * They cannot be enabled earlier because with CONFIG_PREEMPTION=y
      * kernel_thread() would trigger might_sleep() splats. With
      * CONFIG_PREEMPT_VOLUNTARY=y the init task might have scheduled
      * already, but it's stuck on the kthreadd_done completion.
      */
     system_state = SYSTEM_SCHEDULING;
 
     complete(&kthreadd_done);
 
     /*
      * The boot idle thread must execute schedule()
      * at least once to get things moving:
      */
     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, void *arg)
 {
     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, NULL,
            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;
 }
 
 void __init __weak arch_post_acpi_subsys_init(void) { }
 
 void __init __weak smp_setup_processor_id(void)
 {
 }
 
 # if THREAD_SIZE >= PAGE_SIZE
 void __init __weak thread_stack_cache_init(void)
 {
 }
 #endif
 
 void __init __weak mem_encrypt_init(void) { }
 
 void __init __weak poking_init(void) { }
 
 void __init __weak pgtable_cache_init(void) { }
 
 void __init __weak trap_init(void) { }
 
 bool initcall_debug;
 core_param(initcall_debug, initcall_debug, bool, 0644);
 
 #ifdef TRACEPOINTS_ENABLED
 static void __init initcall_debug_enable(void);
 #else
 static inline void initcall_debug_enable(void)
 {
 }
 #endif
 
 /* Report memory auto-initialization states for this boot. */
 static void __init report_meminit(void)
 {
     const char *stack;
 
     if (IS_ENABLED(CONFIG_INIT_STACK_ALL_PATTERN))
         stack = "all(pattern)";
     else if (IS_ENABLED(CONFIG_INIT_STACK_ALL_ZERO))
         stack = "all(zero)";
     else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL))
         stack = "byref_all(zero)";
     else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF))
         stack = "byref(zero)";
     else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_USER))
         stack = "__user(zero)";
     else
         stack = "off";
 
     pr_info("mem auto-init: stack:%s, heap alloc:%s, heap free:%s\n",
         stack, want_init_on_alloc(GFP_KERNEL) ? "on" : "off",
         want_init_on_free() ? "on" : "off");
     if (want_init_on_free())
         pr_info("mem auto-init: clearing system memory may take some time...\n");
 }
 
 /*
  * 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();
     init_mem_debugging_and_hardening();
     kfence_alloc_pool();
     report_meminit();
     stack_depot_early_init();
     mem_init();
     mem_init_print_info();
     kmem_cache_init();
     /*
      * page_owner must be initialized after buddy is ready, and also after
      * slab is ready so that stack_depot_init() works properly
      */
     page_ext_init_flatmem_late();
     kmemleak_init();
     pgtable_init();
     debug_objects_mem_init();
     vmalloc_init();
     /* Should be run before the first non-init thread is created */
     init_espfix_bsp();
     /* Should be run after espfix64 is set up. */
     pti_init();
 }
 
 #ifdef CONFIG_RANDOMIZE_KSTACK_OFFSET
 DEFINE_STATIC_KEY_MAYBE_RO(CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT,
                randomize_kstack_offset);
 DEFINE_PER_CPU(u32, kstack_offset);
 
 static int __init early_randomize_kstack_offset(char *buf)
 {
     int ret;
     bool bool_result;
 
     ret = kstrtobool(buf, &bool_result);
     if (ret)
         return ret;
 
     if (bool_result)
         static_branch_enable(&randomize_kstack_offset);
     else
         static_branch_disable(&randomize_kstack_offset);
     return 0;
 }
 early_param("randomize_kstack_offset", early_randomize_kstack_offset);
 #endif
 
 void __init __weak arch_call_rest_init(void)
 {
     rest_init();
 }
 
 static void __init print_unknown_bootoptions(void)
 {
     char *unknown_options;
     char *end;
     const char *const *p;
     size_t len;
 
     if (panic_later || (!argv_init[1] && !envp_init[2]))
         return;
 
     /*
      * Determine how many options we have to print out, plus a space
      * before each
      */
     len = 1; /* null terminator */
     for (p = &argv_init[1]; *p; p++) {
         len++;
         len += strlen(*p);
     }
     for (p = &envp_init[2]; *p; p++) {
         len++;
         len += strlen(*p);
     }
 
     unknown_options = memblock_alloc(len, SMP_CACHE_BYTES);
     if (!unknown_options) {
         pr_err("%s: Failed to allocate %zu bytes\n",
             __func__, len);
         return;
     }
     end = unknown_options;
 
     for (p = &argv_init[1]; *p; p++)
         end += sprintf(end, " %s", *p);
     for (p = &envp_init[2]; *p; p++)
         end += sprintf(end, " %s", *p);
 
     /* Start at unknown_options[1] to skip the initial space */
     pr_notice("Unknown kernel command line parameters \"%s\", will be passed to user space.\n",
         &unknown_options[1]);
     memblock_free(unknown_options, len);
 }
 
 asmlinkage __visible void __init __no_sanitize_address start_kernel(void)
 {
     char *command_line;
     char *after_dashes;
 
     set_task_stack_end_magic(&init_task);
     smp_setup_processor_id();
     debug_objects_early_init();
     init_vmlinux_build_id();
 
     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);
     early_security_init();
     setup_arch(&command_line);
     setup_boot_config();
     setup_command_line(command_line);
     setup_nr_cpu_ids();
     setup_per_cpu_areas();
     smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
     boot_cpu_hotplug_init();
 
     build_all_zonelists(NULL);
     page_alloc_init();
 
     pr_notice("Kernel command line: %s\n", saved_command_line);
     /* parameters may set static keys */
     jump_label_init();
     parse_early_param();
     after_dashes = parse_args("Booting kernel",
                   static_command_line, __start___param,
                   __stop___param - __start___param,
                   -1, -1, NULL, &unknown_bootoption);
     print_unknown_bootoptions();
     if (!IS_ERR_OR_NULL(after_dashes))
         parse_args("Setting init args", after_dashes, NULL, 0, -1, -1,
                NULL, set_init_arg);
     if (extra_init_args)
         parse_args("Setting extra init args", extra_init_args,
                NULL, 0, -1, -1, NULL, set_init_arg);
 
     /*
      * These use large bootmem allocations and must precede
      * kmem_cache_init()
      */
     setup_log_buf(0);
     vfs_caches_init_early();
     sort_main_extable();
     trap_init();
     mm_init();
 
     ftrace_init();
 
     /* trace_printk can be enabled here */
     early_trace_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();
 
     if (WARN(!irqs_disabled(),
          "Interrupts were enabled *very* early, fixing it\n"))
         local_irq_disable();
     radix_tree_init();
 
     /*
      * Set up housekeeping before setting up workqueues to allow the unbound
      * workqueue to take non-housekeeping into account.
      */
     housekeeping_init();
 
     /*
      * Allow workqueue creation and work item queueing/cancelling
      * early.  Work item execution depends on kthreads and starts after
      * workqueue_init().
      */
     workqueue_init_early();
 
     rcu_init();
 
     /* Trace events are available after this */
     trace_init();
 
     if (initcall_debug)
         initcall_debug_enable();
 
     context_tracking_init();
     /* init some links before init_ISA_irqs() */
     early_irq_init();
     init_IRQ();
     tick_init();
     rcu_init_nohz();
     init_timers();
     srcu_init();
     hrtimers_init();
     softirq_init();
     timekeeping_init();
     kfence_init();
     time_init();
 
     /*
      * For best initial stack canary entropy, prepare it after:
      * - setup_arch() for any UEFI RNG entropy and boot cmdline access
      * - timekeeping_init() for ktime entropy used in random_init()
      * - time_init() for making random_get_entropy() work on some platforms
      * - random_init() to initialize the RNG from from early entropy sources
      */
     random_init(command_line);
     boot_init_stack_canary();
 
     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_init();
 
     /*
      * 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();
 
     /*
      * This needs to be called before any devices perform DMA
      * operations that might use the SWIOTLB bounce buffers. It will
      * mark the bounce buffers as decrypted so that their usage will
      * not cause "plain-text" data to be decrypted when accessed.
      */
     mem_encrypt_init();
 
 #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
     setup_per_cpu_pageset();
     numa_policy_init();
     acpi_early_init();
     if (late_time_init)
         late_time_init();
     sched_clock_init();
     calibrate_delay();
     pid_idr_init();
     anon_vma_init();
 #ifdef CONFIG_X86
     if (efi_enabled(EFI_RUNTIME_SERVICES))
         efi_enter_virtual_mode();
 #endif
     thread_stack_cache_init();
     cred_init();
     fork_init();
     proc_caches_init();
     uts_ns_init();
     key_init();
     security_init();
     dbg_late_init();
     net_ns_init();
     vfs_caches_init();
     pagecache_init();
     signals_init();
     seq_file_init();
     proc_root_init();
     nsfs_init();
     cpuset_init();
     cgroup_init();
     taskstats_init_early();
     delayacct_init();
 
     poking_init();
     check_bugs();
 
     acpi_subsystem_init();
     arch_post_acpi_subsys_init();
     kcsan_init();
 
     /* Do the rest non-__init'ed, we're now alive */
     arch_call_rest_init();
 
     prevent_tail_call_optimization();
 }
 
 /* Call all constructor functions linked into the kernel. */
 static void __init do_ctors(void)
 {
 /*
  * For UML, the constructors have already been called by the
  * normal setup code as it's just a normal ELF binary, so we
  * cannot do it again - but we do need CONFIG_CONSTRUCTORS
  * even on UML for modules.
  */
 #if defined(CONFIG_CONSTRUCTORS) && !defined(CONFIG_UML)
     ctor_fn_t *fn = (ctor_fn_t *) __ctors_start;
 
     for (; fn < (ctor_fn_t *) __ctors_end; fn++)
         (*fn)();
 #endif
 }
 
 #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 = memblock_alloc(sizeof(*entry),
                            SMP_CACHE_BYTES);
             if (!entry)
                 panic("%s: Failed to allocate %zu bytes\n",
                       __func__, sizeof(*entry));
             entry->buf = memblock_alloc(strlen(str_entry) + 1,
                             SMP_CACHE_BYTES);
             if (!entry->buf)
                 panic("%s: Failed to allocate %zu bytes\n",
                       __func__, strlen(str_entry) + 1);
             strcpy(entry->buf, str_entry);
             list_add(&entry->next, &blacklisted_initcalls);
         }
     } while (str_entry);
 
     return 1;
 }
 
 static bool __init_or_module initcall_blacklisted(initcall_t fn)
 {
     struct blacklist_entry *entry;
     char fn_name[KSYM_SYMBOL_LEN];
     unsigned long addr;
 
     if (list_empty(&blacklisted_initcalls))
         return false;
 
     addr = (unsigned long) dereference_function_descriptor(fn);
     sprint_symbol_no_offset(fn_name, addr);
 
     /*
      * fn will be "function_name [module_name]" where [module_name] is not
      * displayed for built-in init functions.  Strip off the [module_name].
      */
     strreplace(fn_name, ' ', '\0');
 
     list_for_each_entry(entry, &blacklisted_initcalls, next) {
         if (!strcmp(fn_name, entry->buf)) {
             pr_debug("initcall %s blacklisted\n", fn_name);
             return true;
         }
     }
 
     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 __init_or_module void
 trace_initcall_start_cb(void *data, initcall_t fn)
 {
     ktime_t *calltime = (ktime_t *)data;
 
     printk(KERN_DEBUG "calling  %pS @ %i\n", fn, task_pid_nr(current));
     *calltime = ktime_get();
 }
 
 static __init_or_module void
 trace_initcall_finish_cb(void *data, initcall_t fn, int ret)
 {
     ktime_t rettime, *calltime = (ktime_t *)data;
 
     rettime = ktime_get();
     printk(KERN_DEBUG "initcall %pS returned %d after %lld usecs\n",
          fn, ret, (unsigned long long)ktime_us_delta(rettime, *calltime));
 }
 
 static ktime_t initcall_calltime;
 
 #ifdef TRACEPOINTS_ENABLED
 static void __init initcall_debug_enable(void)
 {
     int ret;
 
     ret = register_trace_initcall_start(trace_initcall_start_cb,
                         &initcall_calltime);
     ret |= register_trace_initcall_finish(trace_initcall_finish_cb,
                           &initcall_calltime);
     WARN(ret, "Failed to register initcall tracepoints\n");
 }
 # define do_trace_initcall_start    trace_initcall_start
 # define do_trace_initcall_finish   trace_initcall_finish
 #else
 static inline void do_trace_initcall_start(initcall_t fn)
 {
     if (!initcall_debug)
         return;
     trace_initcall_start_cb(&initcall_calltime, fn);
 }
 static inline void do_trace_initcall_finish(initcall_t fn, int ret)
 {
     if (!initcall_debug)
         return;
     trace_initcall_finish_cb(&initcall_calltime, fn, ret);
 }
 #endif /* !TRACEPOINTS_ENABLED */
 
 int __init_or_module do_one_initcall(initcall_t fn)
 {
     int count = preempt_count();
     char msgbuf[64];
     int ret;
 
     if (initcall_blacklisted(fn))
         return -EPERM;
 
     do_trace_initcall_start(fn);
     ret = fn();
     do_trace_initcall_finish(fn, ret);
 
     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 %pS returned with %s\n", fn, msgbuf);
 
     add_latent_entropy();
     return ret;
 }
 
 
 extern initcall_entry_t __initcall_start[];
 extern initcall_entry_t __initcall0_start[];
 extern initcall_entry_t __initcall1_start[];
 extern initcall_entry_t __initcall2_start[];
 extern initcall_entry_t __initcall3_start[];
 extern initcall_entry_t __initcall4_start[];
 extern initcall_entry_t __initcall5_start[];
 extern initcall_entry_t __initcall6_start[];
 extern initcall_entry_t __initcall7_start[];
 extern initcall_entry_t __initcall_end[];
 
 static initcall_entry_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 const char *initcall_level_names[] __initdata = {
     "pure",
     "core",
     "postcore",
     "arch",
     "subsys",
     "fs",
     "device",
     "late",
 };
 
 static int __init ignore_unknown_bootoption(char *param, char *val,
                    const char *unused, void *arg)
 {
     return 0;
 }
 
 static void __init do_initcall_level(int level, char *command_line)
 {
     initcall_entry_t *fn;
 
     parse_args(initcall_level_names[level],
            command_line, __start___param,
            __stop___param - __start___param,
            level, level,
            NULL, ignore_unknown_bootoption);
 
     trace_initcall_level(initcall_level_names[level]);
     for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++)
         do_one_initcall(initcall_from_entry(fn));
 }
 
 static void __init do_initcalls(void)
 {
     int level;
     size_t len = strlen(saved_command_line) + 1;
     char *command_line;
 
     command_line = kzalloc(len, GFP_KERNEL);
     if (!command_line)
         panic("%s: Failed to allocate %zu bytes\n", __func__, len);
 
     for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) {
         /* Parser modifies command_line, restore it each time */
         strcpy(command_line, saved_command_line);
         do_initcall_level(level, command_line);
     }
 
     kfree(command_line);
 }
 
 /*
  * 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();
     driver_init();
     init_irq_proc();
     do_ctors();
     do_initcalls();
 }
 
 static void __init do_pre_smp_initcalls(void)
 {
     initcall_entry_t *fn;
 
     trace_initcall_level("early");
     for (fn = __initcall_start; fn < __initcall0_start; fn++)
         do_one_initcall(initcall_from_entry(fn));
 }
 
 static int run_init_process(const char *init_filename)
 {
     const char *const *p;
 
     argv_init[0] = init_filename;
     pr_info("Run %s as init process\n", init_filename);
     pr_debug("  with arguments:\n");
     for (p = argv_init; *p; p++)
         pr_debug("    %s\n", *p);
     pr_debug("  with environment:\n");
     for (p = envp_init; *p; p++)
         pr_debug("    %s\n", *p);
     return kernel_execve(init_filename, argv_init, 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);
 
 #if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX)
 bool rodata_enabled __ro_after_init = true;
 
 #ifndef arch_parse_debug_rodata
 static inline bool arch_parse_debug_rodata(char *str) { return false; }
 #endif
 
 static int __init set_debug_rodata(char *str)
 {
     if (arch_parse_debug_rodata(str))
         return 0;
 
     if (str && !strcmp(str, "on"))
         rodata_enabled = true;
     else if (str && !strcmp(str, "off"))
         rodata_enabled = false;
     else
         pr_warn("Invalid option string for rodata: '%s'\n", str);
     return 0;
 }
 early_param("rodata", set_debug_rodata);
 #endif
 
 #ifdef CONFIG_STRICT_KERNEL_RWX
 static void mark_readonly(void)
 {
     if (rodata_enabled) {
         /*
          * load_module() results in W+X mappings, which are cleaned
          * up with call_rcu().  Let's make sure that queued work is
          * flushed so that we don't hit false positives looking for
          * insecure pages which are W+X.
          */
         rcu_barrier();
         mark_rodata_ro();
         rodata_test();
     } else
         pr_info("Kernel memory protection disabled.\n");
 }
 #elif defined(CONFIG_ARCH_HAS_STRICT_KERNEL_RWX)
 static inline void mark_readonly(void)
 {
     pr_warn("Kernel memory protection not selected by kernel config.\n");
 }
 #else
 static inline void mark_readonly(void)
 {
     pr_warn("This architecture does not have kernel memory protection.\n");
 }
 #endif
 
 void __weak free_initmem(void)
 {
     free_initmem_default(POISON_FREE_INITMEM);
 }
 
 static int __ref kernel_init(void *unused)
 {
     int ret;
 
     /*
      * Wait until kthreadd is all set-up.
      */
     wait_for_completion(&kthreadd_done);
 
     kernel_init_freeable();
     /* need to finish all async __init code before freeing the memory */
     async_synchronize_full();
 
     system_state = SYSTEM_FREEING_INITMEM;
     kprobe_free_init_mem();
     ftrace_free_init_mem();
     kgdb_free_init_mem();
     exit_boot_config();
     free_initmem();
     mark_readonly();
 
     /*
      * Kernel mappings are now finalized - update the userspace page-table
      * to finalize PTI.
      */
     pti_finalize();
 
     system_state = SYSTEM_RUNNING;
     numa_default_policy();
 
     rcu_end_inkernel_boot();
 
     do_sysctl_args();
 
     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 (CONFIG_DEFAULT_INIT[0] != '\0') {
         ret = run_init_process(CONFIG_DEFAULT_INIT);
         if (ret)
             pr_err("Default init %s failed (error %d)\n",
                    CONFIG_DEFAULT_INIT, ret);
         else
             return 0;
     }
 
     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/admin-guide/init.rst for guidance.");
 }
 
 /* Open /dev/console, for stdin/stdout/stderr, this should never fail */
 void __init console_on_rootfs(void)
 {
     struct file *file = filp_open("/dev/console", O_RDWR, 0);
 
     if (IS_ERR(file)) {
         pr_err("Warning: unable to open an initial console.\n");
         return;
     }
     init_dup(file);
     init_dup(file);
     init_dup(file);
     fput(file);
 }
 
 static noinline void __init kernel_init_freeable(void)
 {
     /* 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]);
 
     cad_pid = get_pid(task_pid(current));
 
     smp_prepare_cpus(setup_max_cpus);
 
     workqueue_init();
 
     init_mm_internals();
 
     rcu_init_tasks_generic();
     do_pre_smp_initcalls();
     lockup_detector_init();
 
     smp_init();
     sched_init_smp();
 
     padata_init();
     page_alloc_init_late();
     /* Initialize page ext after all struct pages are initialized. */
     page_ext_init();
 
     do_basic_setup();
 
     kunit_run_all_tests();
 
     wait_for_initramfs();
     console_on_rootfs();
 
     /*
      * check if there is an early userspace init.  If yes, let it do all
      * the work
      */
     if (init_eaccess(ramdisk_execute_command) != 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();
 }

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