init/init_task.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/init_task.h>
   3 #include <linux/export.h>
   4 #include <linux/mqueue.h>
   5 #include <linux/sched.h>
   6 #include <linux/sched/sysctl.h>
   7 #include <linux/sched/rt.h>
   8 #include <linux/sched/task.h>
   9 #include <linux/init.h>
  10 #include <linux/fs.h>
  11 #include <linux/mm.h>
  12 #include <linux/audit.h>
  13 #include <linux/numa.h>
  14 #include <linux/scs.h>
  15
  16 #include <asm/pgtable.h>
  17 #include <linux/uaccess.h>
  18
  19 static struct signal_struct init_signals = {
  20         .nr_threads     = 1,
  21         .thread_head    = LIST_HEAD_INIT(init_task.thread_node),
  22         .wait_chldexit  = __WAIT_QUEUE_HEAD_INITIALIZER(init_signals.wait_chldexit),
  23         .shared_pending = {
  24                 .list = LIST_HEAD_INIT(init_signals.shared_pending.list),
  25                 .signal =  {{0}}
  26         },
  27         .multiprocess   = HLIST_HEAD_INIT,
  28         .rlim           = INIT_RLIMITS,
  29         .cred_guard_mutex = __MUTEX_INITIALIZER(init_signals.cred_guard_mutex),
  30         .exec_update_mutex = __MUTEX_INITIALIZER(init_signals.exec_update_mutex),
  31 #ifdef CONFIG_POSIX_TIMERS
  32         .posix_timers = LIST_HEAD_INIT(init_signals.posix_timers),
  33         .cputimer       = {
  34                 .cputime_atomic = INIT_CPUTIME_ATOMIC,
  35         },
  36 #endif
  37         INIT_CPU_TIMERS(init_signals)
  38         .pids = {
  39                 [PIDTYPE_PID]   = &init_struct_pid,
  40                 [PIDTYPE_TGID]  = &init_struct_pid,
  41                 [PIDTYPE_PGID]  = &init_struct_pid,
  42                 [PIDTYPE_SID]   = &init_struct_pid,
  43         },
  44         INIT_PREV_CPUTIME(init_signals)
  45 };
  46
  47 static struct sighand_struct init_sighand = {
  48         .count          = REFCOUNT_INIT(1),
  49         .action         = { { { .sa_handler = SIG_DFL, } }, },
  50         .siglock        = __SPIN_LOCK_UNLOCKED(init_sighand.siglock),
  51         .signalfd_wqh   = __WAIT_QUEUE_HEAD_INITIALIZER(init_sighand.signalfd_wqh),
  52 };
  53
  54 #ifdef CONFIG_SHADOW_CALL_STACK
  55 unsigned long init_shadow_call_stack[SCS_SIZE / sizeof(long)]
  56                 __init_task_data = {
  57         [(SCS_SIZE / sizeof(long)) - 1] = SCS_END_MAGIC
  58 };
  59 #endif
  60
  61 /*
  62  * Set up the first task table, touch at your own risk!. Base=0,
  63  * limit=0x1fffff (=2MB)
  64  */
  65 struct task_struct init_task
  66 #ifdef CONFIG_ARCH_TASK_STRUCT_ON_STACK
  67         __init_task_data
  68 #endif
  69 = {
  70 #ifdef CONFIG_THREAD_INFO_IN_TASK
  71         .thread_info    = INIT_THREAD_INFO(init_task),
  72         .stack_refcount = REFCOUNT_INIT(1),
  73 #endif
  74         .state          = 0,
  75         .stack          = init_stack,
  76         .usage          = REFCOUNT_INIT(2),
  77         .flags          = PF_KTHREAD,
  78         .prio           = MAX_PRIO - 20,
  79         .static_prio    = MAX_PRIO - 20,
  80         .normal_prio    = MAX_PRIO - 20,
  81         .policy         = SCHED_NORMAL,
  82         .cpus_ptr       = &init_task.cpus_mask,
  83         .cpus_mask      = CPU_MASK_ALL,
  84         .nr_cpus_allowed= NR_CPUS,
  85         .mm             = NULL,
  86         .active_mm      = &init_mm,
  87         .restart_block  = {
  88                 .fn = do_no_restart_syscall,
  89         },
  90         .se             = {
  91                 .group_node     = LIST_HEAD_INIT(init_task.se.group_node),
  92         },
  93         .rt             = {
  94                 .run_list       = LIST_HEAD_INIT(init_task.rt.run_list),
  95                 .time_slice     = RR_TIMESLICE,
  96         },
  97         .tasks          = LIST_HEAD_INIT(init_task.tasks),
  98 #ifdef CONFIG_SMP
  99         .pushable_tasks = PLIST_NODE_INIT(init_task.pushable_tasks, MAX_PRIO),
 100 #endif
 101 #ifdef CONFIG_CGROUP_SCHED
 102         .sched_task_group = &root_task_group,
 103 #endif
 104         .ptraced        = LIST_HEAD_INIT(init_task.ptraced),
 105         .ptrace_entry   = LIST_HEAD_INIT(init_task.ptrace_entry),
 106         .real_parent    = &init_task,
 107         .parent         = &init_task,
 108         .children       = LIST_HEAD_INIT(init_task.children),
 109         .sibling        = LIST_HEAD_INIT(init_task.sibling),
 110         .group_leader   = &init_task,
 111         RCU_POINTER_INITIALIZER(real_cred, &init_cred),
 112         RCU_POINTER_INITIALIZER(cred, &init_cred),
 113         .comm           = INIT_TASK_COMM,
 114         .thread         = INIT_THREAD,
 115         .fs             = &init_fs,
 116         .files          = &init_files,
 117         .signal         = &init_signals,
 118         .sighand        = &init_sighand,
 119         .nsproxy        = &init_nsproxy,
 120         .pending        = {
 121                 .list = LIST_HEAD_INIT(init_task.pending.list),
 122                 .signal = {{0}}
 123         },
 124         .blocked        = {{0}},
 125         .alloc_lock     = __SPIN_LOCK_UNLOCKED(init_task.alloc_lock),
 126         .journal_info   = NULL,
 127         INIT_CPU_TIMERS(init_task)
 128         .pi_lock        = __RAW_SPIN_LOCK_UNLOCKED(init_task.pi_lock),
 129         .timer_slack_ns = 50000, /* 50 usec default slack */
 130         .thread_pid     = &init_struct_pid,
 131         .thread_group   = LIST_HEAD_INIT(init_task.thread_group),
 132         .thread_node    = LIST_HEAD_INIT(init_signals.thread_head),
 133 #ifdef CONFIG_AUDIT
 134         .loginuid       = INVALID_UID,
 135         .sessionid      = AUDIT_SID_UNSET,
 136 #endif
 137 #ifdef CONFIG_PERF_EVENTS
 138         .perf_event_mutex = __MUTEX_INITIALIZER(init_task.perf_event_mutex),
 139         .perf_event_list = LIST_HEAD_INIT(init_task.perf_event_list),
 140 #endif
 141 #ifdef CONFIG_PREEMPT_RCU
 142         .rcu_read_lock_nesting = 0,
 143         .rcu_read_unlock_special.s = 0,
 144         .rcu_node_entry = LIST_HEAD_INIT(init_task.rcu_node_entry),
 145         .rcu_blocked_node = NULL,
 146 #endif
 147 #ifdef CONFIG_TASKS_RCU
 148         .rcu_tasks_holdout = false,
 149         .rcu_tasks_holdout_list = LIST_HEAD_INIT(init_task.rcu_tasks_holdout_list),
 150         .rcu_tasks_idle_cpu = -1,
 151 #endif
 152 #ifdef CONFIG_TASKS_TRACE_RCU
 153         .trc_reader_nesting = 0,
 154         .trc_reader_special.s = 0,
 155         .trc_holdout_list = LIST_HEAD_INIT(init_task.trc_holdout_list),
 156 #endif
 157 #ifdef CONFIG_CPUSETS
 158         .mems_allowed_seq = SEQCNT_ZERO(init_task.mems_allowed_seq),
 159 #endif
 160 #ifdef CONFIG_RT_MUTEXES
 161         .pi_waiters     = RB_ROOT_CACHED,
 162         .pi_top_task    = NULL,
 163 #endif
 164         INIT_PREV_CPUTIME(init_task)
 165 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
 166         .vtime.seqcount = SEQCNT_ZERO(init_task.vtime_seqcount),
 167         .vtime.starttime = 0,
 168         .vtime.state    = VTIME_SYS,
 169 #endif
 170 #ifdef CONFIG_NUMA_BALANCING
 171         .numa_preferred_nid = NUMA_NO_NODE,
 172         .numa_group     = NULL,
 173         .numa_faults    = NULL,
 174 #endif
 175 #ifdef CONFIG_KASAN
 176         .kasan_depth    = 1,
 177 #endif
 178 #ifdef CONFIG_TRACE_IRQFLAGS
 179         .softirqs_enabled = 1,
 180 #endif
 181 #ifdef CONFIG_LOCKDEP
 182         .lockdep_depth = 0, /* no locks held yet */
 183         .curr_chain_key = INITIAL_CHAIN_KEY,
 184         .lockdep_recursion = 0,
 185 #endif
 186 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 187         .ret_stack      = NULL,
 188 #endif
 189 #if defined(CONFIG_TRACING) && defined(CONFIG_PREEMPTION)
 190         .trace_recursion = 0,
 191 #endif
 192 #ifdef CONFIG_LIVEPATCH
 193         .patch_state    = KLP_UNDEFINED,
 194 #endif
 195 #ifdef CONFIG_SECURITY
 196         .security       = NULL,
 197 #endif
 198 };
 199 EXPORT_SYMBOL(init_task);
 200
 201 /*
 202  * Initial thread structure. Alignment of this is handled by a special
 203  * linker map entry.
 204  */
 205 #ifndef CONFIG_THREAD_INFO_IN_TASK
 206 struct thread_info init_thread_info __init_thread_info = INIT_THREAD_INFO(init_task);
 207 #endif