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         .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 #ifdef CONFIG_IO_URING
 118         .io_uring       = NULL,
 119 #endif
 120         .signal         = &init_signals,
 121         .sighand        = &init_sighand,
 122         .nsproxy        = &init_nsproxy,
 123         .pending        = {
 124                 .list = LIST_HEAD_INIT(init_task.pending.list),
 125                 .signal = {{0}}
 126         },
 127         .blocked        = {{0}},
 128         .alloc_lock     = __SPIN_LOCK_UNLOCKED(init_task.alloc_lock),
 129         .journal_info   = NULL,
 130         INIT_CPU_TIMERS(init_task)
 131         .pi_lock        = __RAW_SPIN_LOCK_UNLOCKED(init_task.pi_lock),
 132         .timer_slack_ns = 50000, /* 50 usec default slack */
 133         .thread_pid     = &init_struct_pid,
 134         .thread_group   = LIST_HEAD_INIT(init_task.thread_group),
 135         .thread_node    = LIST_HEAD_INIT(init_signals.thread_head),
 136 #ifdef CONFIG_AUDIT
 137         .loginuid       = INVALID_UID,
 138         .sessionid      = AUDIT_SID_UNSET,
 139 #endif
 140 #ifdef CONFIG_PERF_EVENTS
 141         .perf_event_mutex = __MUTEX_INITIALIZER(init_task.perf_event_mutex),
 142         .perf_event_list = LIST_HEAD_INIT(init_task.perf_event_list),
 143 #endif
 144 #ifdef CONFIG_PREEMPT_RCU
 145         .rcu_read_lock_nesting = 0,
 146         .rcu_read_unlock_special.s = 0,
 147         .rcu_node_entry = LIST_HEAD_INIT(init_task.rcu_node_entry),
 148         .rcu_blocked_node = NULL,
 149 #endif
 150 #ifdef CONFIG_TASKS_RCU
 151         .rcu_tasks_holdout = false,
 152         .rcu_tasks_holdout_list = LIST_HEAD_INIT(init_task.rcu_tasks_holdout_list),
 153         .rcu_tasks_idle_cpu = -1,
 154 #endif
 155 #ifdef CONFIG_TASKS_TRACE_RCU
 156         .trc_reader_nesting = 0,
 157         .trc_reader_special.s = 0,
 158         .trc_holdout_list = LIST_HEAD_INIT(init_task.trc_holdout_list),
 159 #endif
 160 #ifdef CONFIG_CPUSETS
 161         .mems_allowed_seq = SEQCNT_SPINLOCK_ZERO(init_task.mems_allowed_seq,
 162                                                  &init_task.alloc_lock),
 163 #endif
 164 #ifdef CONFIG_RT_MUTEXES
 165         .pi_waiters     = RB_ROOT_CACHED,
 166         .pi_top_task    = NULL,
 167 #endif
 168         INIT_PREV_CPUTIME(init_task)
 169 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
 170         .vtime.seqcount = SEQCNT_ZERO(init_task.vtime_seqcount),
 171         .vtime.starttime = 0,
 172         .vtime.state    = VTIME_SYS,
 173 #endif
 174 #ifdef CONFIG_NUMA_BALANCING
 175         .numa_preferred_nid = NUMA_NO_NODE,
 176         .numa_group     = NULL,
 177         .numa_faults    = NULL,
 178 #endif
 179 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 180         .kasan_depth    = 1,
 181 #endif
 182 #ifdef CONFIG_KCSAN
 183         .kcsan_ctx = {
 184                 .disable_count          = 0,
 185                 .atomic_next            = 0,
 186                 .atomic_nest_count      = 0,
 187                 .in_flat_atomic         = false,
 188                 .access_mask            = 0,
 189                 .scoped_accesses        = {LIST_POISON1, NULL},
 190         },
 191 #endif
 192 #ifdef CONFIG_TRACE_IRQFLAGS
 193         .softirqs_enabled = 1,
 194 #endif
 195 #ifdef CONFIG_LOCKDEP
 196         .lockdep_depth = 0, /* no locks held yet */
 197         .curr_chain_key = INITIAL_CHAIN_KEY,
 198         .lockdep_recursion = 0,
 199 #endif
 200 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 201         .ret_stack              = NULL,
 202         .tracing_graph_pause    = ATOMIC_INIT(0),
 203 #endif
 204 #if defined(CONFIG_TRACING) && defined(CONFIG_PREEMPTION)
 205         .trace_recursion = 0,
 206 #endif
 207 #ifdef CONFIG_LIVEPATCH
 208         .patch_state    = KLP_UNDEFINED,
 209 #endif
 210 #ifdef CONFIG_SECURITY
 211         .security       = NULL,
 212 #endif
 213 #ifdef CONFIG_SECCOMP
 214         .seccomp        = { .filter_count = ATOMIC_INIT(0) },
 215 #endif
 216 };
 217 EXPORT_SYMBOL(init_task);
 218
 219 /*
 220  * Initial thread structure. Alignment of this is handled by a special
 221  * linker map entry.
 222  */
 223 #ifndef CONFIG_THREAD_INFO_IN_TASK
 224 struct thread_info init_thread_info __init_thread_info = INIT_THREAD_INFO(init_task);
 225 #endif