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 <linux/uaccess.h>
  17
  18 static struct signal_struct init_signals = {
  19         .nr_threads     = 1,
  20         .thread_head    = LIST_HEAD_INIT(init_task.thread_node),
  21         .wait_chldexit  = __WAIT_QUEUE_HEAD_INITIALIZER(init_signals.wait_chldexit),
  22         .shared_pending = {
  23                 .list = LIST_HEAD_INIT(init_signals.shared_pending.list),
  24                 .signal =  {{0}}
  25         },
  26         .multiprocess   = HLIST_HEAD_INIT,
  27         .rlim           = INIT_RLIMITS,
  28         .cred_guard_mutex = __MUTEX_INITIALIZER(init_signals.cred_guard_mutex),
  29         .exec_update_lock = __RWSEM_INITIALIZER(init_signals.exec_update_lock),
  30 #ifdef CONFIG_POSIX_TIMERS
  31         .posix_timers = LIST_HEAD_INIT(init_signals.posix_timers),
  32         .cputimer       = {
  33                 .cputime_atomic = INIT_CPUTIME_ATOMIC,
  34         },
  35 #endif
  36         INIT_CPU_TIMERS(init_signals)
  37         .pids = {
  38                 [PIDTYPE_PID]   = &init_struct_pid,
  39                 [PIDTYPE_TGID]  = &init_struct_pid,
  40                 [PIDTYPE_PGID]  = &init_struct_pid,
  41                 [PIDTYPE_SID]   = &init_struct_pid,
  42         },
  43         INIT_PREV_CPUTIME(init_signals)
  44 };
  45
  46 static struct sighand_struct init_sighand = {
  47         .count          = REFCOUNT_INIT(1),
  48         .action         = { { { .sa_handler = SIG_DFL, } }, },
  49         .siglock        = __SPIN_LOCK_UNLOCKED(init_sighand.siglock),
  50         .signalfd_wqh   = __WAIT_QUEUE_HEAD_INITIALIZER(init_sighand.signalfd_wqh),
  51 };
  52
  53 #ifdef CONFIG_SHADOW_CALL_STACK
  54 unsigned long init_shadow_call_stack[SCS_SIZE / sizeof(long)]
  55                 __init_task_data = {
  56         [(SCS_SIZE / sizeof(long)) - 1] = SCS_END_MAGIC
  57 };
  58 #endif
  59
  60 /*
  61  * Set up the first task table, touch at your own risk!. Base=0,
  62  * limit=0x1fffff (=2MB)
  63  */
  64 struct task_struct init_task
  65 #ifdef CONFIG_ARCH_TASK_STRUCT_ON_STACK
  66         __init_task_data
  67 #endif
  68         __aligned(L1_CACHE_BYTES)
  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         .user_cpus_ptr  = NULL,
  84         .cpus_mask      = CPU_MASK_ALL,
  85         .nr_cpus_allowed= NR_CPUS,
  86         .mm             = NULL,
  87         .active_mm      = &init_mm,
  88         .restart_block  = {
  89                 .fn = do_no_restart_syscall,
  90         },
  91         .se             = {
  92                 .group_node     = LIST_HEAD_INIT(init_task.se.group_node),
  93         },
  94         .rt             = {
  95                 .run_list       = LIST_HEAD_INIT(init_task.rt.run_list),
  96                 .time_slice     = RR_TIMESLICE,
  97         },
  98         .tasks          = LIST_HEAD_INIT(init_task.tasks),
  99 #ifdef CONFIG_SMP
 100         .pushable_tasks = PLIST_NODE_INIT(init_task.pushable_tasks, MAX_PRIO),
 101 #endif
 102 #ifdef CONFIG_CGROUP_SCHED
 103         .sched_task_group = &root_task_group,
 104 #endif
 105         .ptraced        = LIST_HEAD_INIT(init_task.ptraced),
 106         .ptrace_entry   = LIST_HEAD_INIT(init_task.ptrace_entry),
 107         .real_parent    = &init_task,
 108         .parent         = &init_task,
 109         .children       = LIST_HEAD_INIT(init_task.children),
 110         .sibling        = LIST_HEAD_INIT(init_task.sibling),
 111         .group_leader   = &init_task,
 112         RCU_POINTER_INITIALIZER(real_cred, &init_cred),
 113         RCU_POINTER_INITIALIZER(cred, &init_cred),
 114         .comm           = INIT_TASK_COMM,
 115         .thread         = INIT_THREAD,
 116         .fs             = &init_fs,
 117         .files          = &init_files,
 118 #ifdef CONFIG_IO_URING
 119         .io_uring       = NULL,
 120 #endif
 121         .signal         = &init_signals,
 122         .sighand        = &init_sighand,
 123         .nsproxy        = &init_nsproxy,
 124         .pending        = {
 125                 .list = LIST_HEAD_INIT(init_task.pending.list),
 126                 .signal = {{0}}
 127         },
 128         .blocked        = {{0}},
 129         .alloc_lock     = __SPIN_LOCK_UNLOCKED(init_task.alloc_lock),
 130         .journal_info   = NULL,
 131         INIT_CPU_TIMERS(init_task)
 132         .pi_lock        = __RAW_SPIN_LOCK_UNLOCKED(init_task.pi_lock),
 133         .timer_slack_ns = 50000, /* 50 usec default slack */
 134         .thread_pid     = &init_struct_pid,
 135         .thread_group   = LIST_HEAD_INIT(init_task.thread_group),
 136         .thread_node    = LIST_HEAD_INIT(init_signals.thread_head),
 137 #ifdef CONFIG_AUDIT
 138         .loginuid       = INVALID_UID,
 139         .sessionid      = AUDIT_SID_UNSET,
 140 #endif
 141 #ifdef CONFIG_PERF_EVENTS
 142         .perf_event_mutex = __MUTEX_INITIALIZER(init_task.perf_event_mutex),
 143         .perf_event_list = LIST_HEAD_INIT(init_task.perf_event_list),
 144 #endif
 145 #ifdef CONFIG_PREEMPT_RCU
 146         .rcu_read_lock_nesting = 0,
 147         .rcu_read_unlock_special.s = 0,
 148         .rcu_node_entry = LIST_HEAD_INIT(init_task.rcu_node_entry),
 149         .rcu_blocked_node = NULL,
 150 #endif
 151 #ifdef CONFIG_TASKS_RCU
 152         .rcu_tasks_holdout = false,
 153         .rcu_tasks_holdout_list = LIST_HEAD_INIT(init_task.rcu_tasks_holdout_list),
 154         .rcu_tasks_idle_cpu = -1,
 155 #endif
 156 #ifdef CONFIG_TASKS_TRACE_RCU
 157         .trc_reader_nesting = 0,
 158         .trc_reader_special.s = 0,
 159         .trc_holdout_list = LIST_HEAD_INIT(init_task.trc_holdout_list),
 160 #endif
 161 #ifdef CONFIG_CPUSETS
 162         .mems_allowed_seq = SEQCNT_SPINLOCK_ZERO(init_task.mems_allowed_seq,
 163                                                  &init_task.alloc_lock),
 164 #endif
 165 #ifdef CONFIG_RT_MUTEXES
 166         .pi_waiters     = RB_ROOT_CACHED,
 167         .pi_top_task    = NULL,
 168 #endif
 169         INIT_PREV_CPUTIME(init_task)
 170 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
 171         .vtime.seqcount = SEQCNT_ZERO(init_task.vtime_seqcount),
 172         .vtime.starttime = 0,
 173         .vtime.state    = VTIME_SYS,
 174 #endif
 175 #ifdef CONFIG_NUMA_BALANCING
 176         .numa_preferred_nid = NUMA_NO_NODE,
 177         .numa_group     = NULL,
 178         .numa_faults    = NULL,
 179 #endif
 180 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 181         .kasan_depth    = 1,
 182 #endif
 183 #ifdef CONFIG_KCSAN
 184         .kcsan_ctx = {
 185                 .scoped_accesses        = {LIST_POISON1, NULL},
 186         },
 187 #endif
 188 #ifdef CONFIG_TRACE_IRQFLAGS
 189         .softirqs_enabled = 1,
 190 #endif
 191 #ifdef CONFIG_LOCKDEP
 192         .lockdep_depth = 0, /* no locks held yet */
 193         .curr_chain_key = INITIAL_CHAIN_KEY,
 194         .lockdep_recursion = 0,
 195 #endif
 196 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 197         .ret_stack              = NULL,
 198         .tracing_graph_pause    = ATOMIC_INIT(0),
 199 #endif
 200 #if defined(CONFIG_TRACING) && defined(CONFIG_PREEMPTION)
 201         .trace_recursion = 0,
 202 #endif
 203 #ifdef CONFIG_LIVEPATCH
 204         .patch_state    = KLP_UNDEFINED,
 205 #endif
 206 #ifdef CONFIG_SECURITY
 207         .security       = NULL,
 208 #endif
 209 #ifdef CONFIG_SECCOMP_FILTER
 210         .seccomp        = { .filter_count = ATOMIC_INIT(0) },
 211 #endif
 212 };
 213 EXPORT_SYMBOL(init_task);
 214
 215 /*
 216  * Initial thread structure. Alignment of this is handled by a special
 217  * linker map entry.
 218  */
 219 #ifndef CONFIG_THREAD_INFO_IN_TASK
 220 struct thread_info init_thread_info __init_thread_info = INIT_THREAD_INFO(init_task);
 221 #endif