73 	struct task_struct *g, *task;  in klp_complete_transition()  local
110 	for_each_process_thread(g, task) {  in klp_complete_transition()
111 		WARN_ON_ONCE(test_tsk_thread_flag(task, TIF_PATCH_PENDING));  in klp_complete_transition()
112 		task->patch_state = KLP_UNDEFINED;  in klp_complete_transition()
117 		task = idle_task(cpu);  in klp_complete_transition()
118 		WARN_ON_ONCE(test_tsk_thread_flag(task, TIF_PATCH_PENDING));  in klp_complete_transition()
119 		task->patch_state = KLP_UNDEFINED;  in klp_complete_transition()
157  * Switch the patched state of the task to the set of functions in the target
160  * NOTE: If task is not 'current', the caller must ensure the task is inactive.
163 void klp_update_patch_state(struct task_struct *task)  in klp_update_patch_state()  argument
183 	if (test_and_clear_tsk_thread_flag(task, TIF_PATCH_PENDING))  in klp_update_patch_state()
184 		task->patch_state = READ_ONCE(klp_target_state);  in klp_update_patch_state()
239  * Determine whether it's safe to transition the task to the target patch state
242 static int klp_check_stack(struct task_struct *task, char *err_buf)  in klp_check_stack()  argument
249 	ret = stack_trace_save_tsk_reliable(task, entries, ARRAY_SIZE(entries));  in klp_check_stack()
253 			 __func__, task->comm, task->pid);  in klp_check_stack()
266 					 __func__, task->comm, task->pid,  in klp_check_stack()
277  * Try to safely switch a task to the target patch state.  If it's currently
281 static bool klp_try_switch_task(struct task_struct *task)  in klp_try_switch_task()  argument
291 	/* check if this task has already switched over */  in klp_try_switch_task()
292 	if (task->patch_state == klp_target_state)  in klp_try_switch_task()
304 	 * functions.  If all goes well, switch the task to the target patch  in klp_try_switch_task()
307 	rq = task_rq_lock(task, &flags);  in klp_try_switch_task()
309 	if (task_running(rq, task) && task != current) {  in klp_try_switch_task()
311 			 "%s: %s:%d is running\n", __func__, task->comm,  in klp_try_switch_task()
312 			 task->pid);  in klp_try_switch_task()
316 	ret = klp_check_stack(task, err_buf);  in klp_try_switch_task()
322 	clear_tsk_thread_flag(task, TIF_PATCH_PENDING);  in klp_try_switch_task()
323 	task->patch_state = klp_target_state;  in klp_try_switch_task()
326 	task_rq_unlock(rq, task, &flags);  in klp_try_switch_task()
330 	 * holding the task rq lock.  Instead we have to use a temporary buffer  in klp_try_switch_task()
345 	struct task_struct *g, *task;  in klp_send_signals()  local
351 	for_each_process_thread(g, task) {  in klp_send_signals()
352 		if (!klp_patch_pending(task))  in klp_send_signals()
358 		 * Meanwhile the task could migrate itself and the action  in klp_send_signals()
361 		if (task->flags & PF_KTHREAD) {  in klp_send_signals()
366 			wake_up_state(task, TASK_INTERRUPTIBLE);  in klp_send_signals()
372 			spin_lock_irq(&task->sighand->siglock);  in klp_send_signals()
373 			signal_wake_up(task, 0);  in klp_send_signals()
374 			spin_unlock_irq(&task->sighand->siglock);  in klp_send_signals()
383  * to-be-unpatched functions.  If such functions are found, the task can't be
391 	struct task_struct *g, *task;  in klp_try_complete_transition()  local
401 	 * is deemed unreliable, the task can't be switched yet.  in klp_try_complete_transition()
407 	for_each_process_thread(g, task)  in klp_try_complete_transition()
408 		if (!klp_try_switch_task(task))  in klp_try_complete_transition()
417 		task = idle_task(cpu);  in klp_try_complete_transition()
419 			if (!klp_try_switch_task(task))  in klp_try_complete_transition()
421 		} else if (task->patch_state != klp_target_state) {  in klp_try_complete_transition()
423 			clear_tsk_thread_flag(task, TIF_PATCH_PENDING);  in klp_try_complete_transition()
424 			task->patch_state = klp_target_state;  in klp_try_complete_transition()
465 	struct task_struct *g, *task;  in klp_start_transition()  local
480 	for_each_process_thread(g, task)  in klp_start_transition()
481 		if (task->patch_state != klp_target_state)  in klp_start_transition()
482 			set_tsk_thread_flag(task, TIF_PATCH_PENDING);  in klp_start_transition()
491 		task = idle_task(cpu);  in klp_start_transition()
492 		if (task->patch_state != klp_target_state)  in klp_start_transition()
493 			set_tsk_thread_flag(task, TIF_PATCH_PENDING);  in klp_start_transition()
506 	struct task_struct *g, *task;  in klp_init_transition()  local
530 	for_each_process_thread(g, task) {  in klp_init_transition()
531 		WARN_ON_ONCE(task->patch_state != KLP_UNDEFINED);  in klp_init_transition()
532 		task->patch_state = initial_state;  in klp_init_transition()
540 		task = idle_task(cpu);  in klp_init_transition()
541 		WARN_ON_ONCE(task->patch_state != KLP_UNDEFINED);  in klp_init_transition()
542 		task->patch_state = initial_state;  in klp_init_transition()
546 	 * Enforce the order of the task->patch_state initializations and the  in klp_init_transition()
548 	 * see a func in transition with a task->patch_state of KLP_UNDEFINED.  in klp_init_transition()
552 	 * set a task->patch_state to KLP_UNDEFINED.  in klp_init_transition()
581 	struct task_struct *g, *task;  in klp_reverse_transition()  local
598 	for_each_process_thread(g, task)  in klp_reverse_transition()
599 		clear_tsk_thread_flag(task, TIF_PATCH_PENDING);  in klp_reverse_transition()
623  * NOTE: klp_update_patch_state(task) requires the task to be inactive or
631 	struct task_struct *g, *task;  in klp_force_transition()  local
637 	for_each_process_thread(g, task)  in klp_force_transition()
638 		klp_update_patch_state(task);  in klp_force_transition()