xref: /linux/init/init_task.c (revision dbcedec3a31119d7594baacc743300d127c99c56)
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 #include <linux/plist.h>
16 
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_lock = __RWSEM_INITIALIZER(init_signals.exec_update_lock),
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 	[(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 __aligned(L1_CACHE_BYTES) = {
65 #ifdef CONFIG_THREAD_INFO_IN_TASK
66 	.thread_info	= INIT_THREAD_INFO(init_task),
67 	.stack_refcount	= REFCOUNT_INIT(1),
68 #endif
69 	.__state	= 0,
70 	.stack		= init_stack,
71 	.usage		= REFCOUNT_INIT(2),
72 	.flags		= PF_KTHREAD,
73 	.prio		= MAX_PRIO - 20,
74 	.static_prio	= MAX_PRIO - 20,
75 	.normal_prio	= MAX_PRIO - 20,
76 	.policy		= SCHED_NORMAL,
77 	.cpus_ptr	= &init_task.cpus_mask,
78 	.user_cpus_ptr	= NULL,
79 	.cpus_mask	= CPU_MASK_ALL,
80 	.nr_cpus_allowed= NR_CPUS,
81 	.mm		= NULL,
82 	.active_mm	= &init_mm,
83 	.faults_disabled_mapping = NULL,
84 	.restart_block	= {
85 		.fn = do_no_restart_syscall,
86 	},
87 	.se		= {
88 		.group_node 	= LIST_HEAD_INIT(init_task.se.group_node),
89 	},
90 	.rt		= {
91 		.run_list	= LIST_HEAD_INIT(init_task.rt.run_list),
92 		.time_slice	= RR_TIMESLICE,
93 	},
94 	.tasks		= LIST_HEAD_INIT(init_task.tasks),
95 #ifdef CONFIG_SMP
96 	.pushable_tasks	= PLIST_NODE_INIT(init_task.pushable_tasks, MAX_PRIO),
97 #endif
98 #ifdef CONFIG_CGROUP_SCHED
99 	.sched_task_group = &root_task_group,
100 #endif
101 	.ptraced	= LIST_HEAD_INIT(init_task.ptraced),
102 	.ptrace_entry	= LIST_HEAD_INIT(init_task.ptrace_entry),
103 	.real_parent	= &init_task,
104 	.parent		= &init_task,
105 	.children	= LIST_HEAD_INIT(init_task.children),
106 	.sibling	= LIST_HEAD_INIT(init_task.sibling),
107 	.group_leader	= &init_task,
108 	RCU_POINTER_INITIALIZER(real_cred, &init_cred),
109 	RCU_POINTER_INITIALIZER(cred, &init_cred),
110 	.comm		= INIT_TASK_COMM,
111 	.thread		= INIT_THREAD,
112 	.fs		= &init_fs,
113 	.files		= &init_files,
114 #ifdef CONFIG_IO_URING
115 	.io_uring	= NULL,
116 #endif
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_node	= LIST_HEAD_INIT(init_signals.thread_head),
132 #ifdef CONFIG_AUDIT
133 	.loginuid	= INVALID_UID,
134 	.sessionid	= AUDIT_SID_UNSET,
135 #endif
136 #ifdef CONFIG_PERF_EVENTS
137 	.perf_event_mutex = __MUTEX_INITIALIZER(init_task.perf_event_mutex),
138 	.perf_event_list = LIST_HEAD_INIT(init_task.perf_event_list),
139 #endif
140 #ifdef CONFIG_PREEMPT_RCU
141 	.rcu_read_lock_nesting = 0,
142 	.rcu_read_unlock_special.s = 0,
143 	.rcu_node_entry = LIST_HEAD_INIT(init_task.rcu_node_entry),
144 	.rcu_blocked_node = NULL,
145 #endif
146 #ifdef CONFIG_TASKS_RCU
147 	.rcu_tasks_holdout = false,
148 	.rcu_tasks_holdout_list = LIST_HEAD_INIT(init_task.rcu_tasks_holdout_list),
149 	.rcu_tasks_idle_cpu = -1,
150 	.rcu_tasks_exit_list = LIST_HEAD_INIT(init_task.rcu_tasks_exit_list),
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 	.trc_blkd_node = LIST_HEAD_INIT(init_task.trc_blkd_node),
157 #endif
158 #ifdef CONFIG_CPUSETS
159 	.mems_allowed_seq = SEQCNT_SPINLOCK_ZERO(init_task.mems_allowed_seq,
160 						 &init_task.alloc_lock),
161 #endif
162 #ifdef CONFIG_RT_MUTEXES
163 	.pi_waiters	= RB_ROOT_CACHED,
164 	.pi_top_task	= NULL,
165 #endif
166 	INIT_PREV_CPUTIME(init_task)
167 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
168 	.vtime.seqcount	= SEQCNT_ZERO(init_task.vtime_seqcount),
169 	.vtime.starttime = 0,
170 	.vtime.state	= VTIME_SYS,
171 #endif
172 #ifdef CONFIG_NUMA_BALANCING
173 	.numa_preferred_nid = NUMA_NO_NODE,
174 	.numa_group	= NULL,
175 	.numa_faults	= NULL,
176 #endif
177 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
178 	.kasan_depth	= 1,
179 #endif
180 #ifdef CONFIG_KCSAN
181 	.kcsan_ctx = {
182 		.scoped_accesses	= {LIST_POISON1, NULL},
183 	},
184 #endif
185 #ifdef CONFIG_TRACE_IRQFLAGS
186 	.softirqs_enabled = 1,
187 #endif
188 #ifdef CONFIG_LOCKDEP
189 	.lockdep_depth = 0, /* no locks held yet */
190 	.curr_chain_key = INITIAL_CHAIN_KEY,
191 	.lockdep_recursion = 0,
192 #endif
193 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
194 	.ret_stack		= NULL,
195 	.tracing_graph_pause	= ATOMIC_INIT(0),
196 #endif
197 #if defined(CONFIG_TRACING) && defined(CONFIG_PREEMPTION)
198 	.trace_recursion = 0,
199 #endif
200 #ifdef CONFIG_LIVEPATCH
201 	.patch_state	= KLP_UNDEFINED,
202 #endif
203 #ifdef CONFIG_SECURITY
204 	.security	= NULL,
205 #endif
206 #ifdef CONFIG_SECCOMP_FILTER
207 	.seccomp	= { .filter_count = ATOMIC_INIT(0) },
208 #endif
209 };
210 EXPORT_SYMBOL(init_task);
211 
212 /*
213  * Initial thread structure. Alignment of this is handled by a special
214  * linker map entry.
215  */
216 #ifndef CONFIG_THREAD_INFO_IN_TASK
217 struct thread_info init_thread_info __init_thread_info = INIT_THREAD_INFO(init_task);
218 #endif
219