xref: /linux/init/init_task.c (revision fcc79e1714e8c2b8e216dc3149812edd37884eef)
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/sched/ext.h>
10 #include <linux/init.h>
11 #include <linux/fs.h>
12 #include <linux/mm.h>
13 #include <linux/audit.h>
14 #include <linux/numa.h>
15 #include <linux/scs.h>
16 #include <linux/plist.h>
17 
18 #include <linux/uaccess.h>
19 
20 static struct signal_struct init_signals = {
21 	.nr_threads	= 1,
22 	.thread_head	= LIST_HEAD_INIT(init_task.thread_node),
23 	.wait_chldexit	= __WAIT_QUEUE_HEAD_INITIALIZER(init_signals.wait_chldexit),
24 	.shared_pending	= {
25 		.list = LIST_HEAD_INIT(init_signals.shared_pending.list),
26 		.signal =  {{0}}
27 	},
28 	.multiprocess	= HLIST_HEAD_INIT,
29 	.rlim		= INIT_RLIMITS,
30 	.cred_guard_mutex = __MUTEX_INITIALIZER(init_signals.cred_guard_mutex),
31 	.exec_update_lock = __RWSEM_INITIALIZER(init_signals.exec_update_lock),
32 #ifdef CONFIG_POSIX_TIMERS
33 	.posix_timers		= HLIST_HEAD_INIT,
34 	.ignored_posix_timers	= HLIST_HEAD_INIT,
35 	.cputimer		= {
36 		.cputime_atomic	= INIT_CPUTIME_ATOMIC,
37 	},
38 #endif
39 	INIT_CPU_TIMERS(init_signals)
40 	.pids = {
41 		[PIDTYPE_PID]	= &init_struct_pid,
42 		[PIDTYPE_TGID]	= &init_struct_pid,
43 		[PIDTYPE_PGID]	= &init_struct_pid,
44 		[PIDTYPE_SID]	= &init_struct_pid,
45 	},
46 	INIT_PREV_CPUTIME(init_signals)
47 };
48 
49 static struct sighand_struct init_sighand = {
50 	.count		= REFCOUNT_INIT(1),
51 	.action		= { { { .sa_handler = SIG_DFL, } }, },
52 	.siglock	= __SPIN_LOCK_UNLOCKED(init_sighand.siglock),
53 	.signalfd_wqh	= __WAIT_QUEUE_HEAD_INITIALIZER(init_sighand.signalfd_wqh),
54 };
55 
56 #ifdef CONFIG_SHADOW_CALL_STACK
57 unsigned long init_shadow_call_stack[SCS_SIZE / sizeof(long)] = {
58 	[(SCS_SIZE / sizeof(long)) - 1] = SCS_END_MAGIC
59 };
60 #endif
61 
62 /*
63  * Set up the first task table, touch at your own risk!. Base=0,
64  * limit=0x1fffff (=2MB)
65  */
66 struct task_struct init_task __aligned(L1_CACHE_BYTES) = {
67 #ifdef CONFIG_THREAD_INFO_IN_TASK
68 	.thread_info	= INIT_THREAD_INFO(init_task),
69 	.stack_refcount	= REFCOUNT_INIT(1),
70 #endif
71 	.__state	= 0,
72 	.stack		= init_stack,
73 	.usage		= REFCOUNT_INIT(2),
74 	.flags		= PF_KTHREAD,
75 	.prio		= MAX_PRIO - 20,
76 	.static_prio	= MAX_PRIO - 20,
77 	.normal_prio	= MAX_PRIO - 20,
78 	.policy		= SCHED_NORMAL,
79 	.cpus_ptr	= &init_task.cpus_mask,
80 	.user_cpus_ptr	= NULL,
81 	.cpus_mask	= CPU_MASK_ALL,
82 	.max_allowed_capacity	= SCHED_CAPACITY_SCALE,
83 	.nr_cpus_allowed= NR_CPUS,
84 	.mm		= NULL,
85 	.active_mm	= &init_mm,
86 	.faults_disabled_mapping = NULL,
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 #ifdef CONFIG_SCHED_CLASS_EXT
105 	.scx		= {
106 		.dsq_list.node	= LIST_HEAD_INIT(init_task.scx.dsq_list.node),
107 		.sticky_cpu	= -1,
108 		.holding_cpu	= -1,
109 		.runnable_node	= LIST_HEAD_INIT(init_task.scx.runnable_node),
110 		.runnable_at	= INITIAL_JIFFIES,
111 		.ddsp_dsq_id	= SCX_DSQ_INVALID,
112 		.slice		= SCX_SLICE_DFL,
113 	},
114 #endif
115 	.ptraced	= LIST_HEAD_INIT(init_task.ptraced),
116 	.ptrace_entry	= LIST_HEAD_INIT(init_task.ptrace_entry),
117 	.real_parent	= &init_task,
118 	.parent		= &init_task,
119 	.children	= LIST_HEAD_INIT(init_task.children),
120 	.sibling	= LIST_HEAD_INIT(init_task.sibling),
121 	.group_leader	= &init_task,
122 	RCU_POINTER_INITIALIZER(real_cred, &init_cred),
123 	RCU_POINTER_INITIALIZER(cred, &init_cred),
124 	.comm		= INIT_TASK_COMM,
125 	.thread		= INIT_THREAD,
126 	.fs		= &init_fs,
127 	.files		= &init_files,
128 #ifdef CONFIG_IO_URING
129 	.io_uring	= NULL,
130 #endif
131 	.signal		= &init_signals,
132 	.sighand	= &init_sighand,
133 	.nsproxy	= &init_nsproxy,
134 	.pending	= {
135 		.list = LIST_HEAD_INIT(init_task.pending.list),
136 		.signal = {{0}}
137 	},
138 	.blocked	= {{0}},
139 	.alloc_lock	= __SPIN_LOCK_UNLOCKED(init_task.alloc_lock),
140 	.journal_info	= NULL,
141 	INIT_CPU_TIMERS(init_task)
142 	.pi_lock	= __RAW_SPIN_LOCK_UNLOCKED(init_task.pi_lock),
143 	.timer_slack_ns = 50000, /* 50 usec default slack */
144 	.thread_pid	= &init_struct_pid,
145 	.thread_node	= LIST_HEAD_INIT(init_signals.thread_head),
146 #ifdef CONFIG_AUDIT
147 	.loginuid	= INVALID_UID,
148 	.sessionid	= AUDIT_SID_UNSET,
149 #endif
150 #ifdef CONFIG_PERF_EVENTS
151 	.perf_event_mutex = __MUTEX_INITIALIZER(init_task.perf_event_mutex),
152 	.perf_event_list = LIST_HEAD_INIT(init_task.perf_event_list),
153 #endif
154 #ifdef CONFIG_PREEMPT_RCU
155 	.rcu_read_lock_nesting = 0,
156 	.rcu_read_unlock_special.s = 0,
157 	.rcu_node_entry = LIST_HEAD_INIT(init_task.rcu_node_entry),
158 	.rcu_blocked_node = NULL,
159 #endif
160 #ifdef CONFIG_TASKS_RCU
161 	.rcu_tasks_holdout = false,
162 	.rcu_tasks_holdout_list = LIST_HEAD_INIT(init_task.rcu_tasks_holdout_list),
163 	.rcu_tasks_idle_cpu = -1,
164 	.rcu_tasks_exit_list = LIST_HEAD_INIT(init_task.rcu_tasks_exit_list),
165 #endif
166 #ifdef CONFIG_TASKS_TRACE_RCU
167 	.trc_reader_nesting = 0,
168 	.trc_reader_special.s = 0,
169 	.trc_holdout_list = LIST_HEAD_INIT(init_task.trc_holdout_list),
170 	.trc_blkd_node = LIST_HEAD_INIT(init_task.trc_blkd_node),
171 #endif
172 #ifdef CONFIG_CPUSETS
173 	.mems_allowed_seq = SEQCNT_SPINLOCK_ZERO(init_task.mems_allowed_seq,
174 						 &init_task.alloc_lock),
175 #endif
176 #ifdef CONFIG_RT_MUTEXES
177 	.pi_waiters	= RB_ROOT_CACHED,
178 	.pi_top_task	= NULL,
179 #endif
180 	INIT_PREV_CPUTIME(init_task)
181 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
182 	.vtime.seqcount	= SEQCNT_ZERO(init_task.vtime_seqcount),
183 	.vtime.starttime = 0,
184 	.vtime.state	= VTIME_SYS,
185 #endif
186 #ifdef CONFIG_NUMA_BALANCING
187 	.numa_preferred_nid = NUMA_NO_NODE,
188 	.numa_group	= NULL,
189 	.numa_faults	= NULL,
190 #endif
191 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
192 	.kasan_depth	= 1,
193 #endif
194 #ifdef CONFIG_KCSAN
195 	.kcsan_ctx = {
196 		.scoped_accesses	= {LIST_POISON1, NULL},
197 	},
198 #endif
199 #ifdef CONFIG_TRACE_IRQFLAGS
200 	.softirqs_enabled = 1,
201 #endif
202 #ifdef CONFIG_LOCKDEP
203 	.lockdep_depth = 0, /* no locks held yet */
204 	.curr_chain_key = INITIAL_CHAIN_KEY,
205 	.lockdep_recursion = 0,
206 #endif
207 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
208 	.ret_stack		= NULL,
209 	.tracing_graph_pause	= ATOMIC_INIT(0),
210 #endif
211 #if defined(CONFIG_TRACING) && defined(CONFIG_PREEMPTION)
212 	.trace_recursion = 0,
213 #endif
214 #ifdef CONFIG_LIVEPATCH
215 	.patch_state	= KLP_TRANSITION_IDLE,
216 #endif
217 #ifdef CONFIG_SECURITY
218 	.security	= NULL,
219 #endif
220 #ifdef CONFIG_SECCOMP_FILTER
221 	.seccomp	= { .filter_count = ATOMIC_INIT(0) },
222 #endif
223 };
224 EXPORT_SYMBOL(init_task);
225 
226 /*
227  * Initial thread structure. Alignment of this is handled by a special
228  * linker map entry.
229  */
230 #ifndef CONFIG_THREAD_INFO_IN_TASK
231 struct thread_info init_thread_info __init_thread_info = INIT_THREAD_INFO(init_task);
232 #endif
233