[PATCH 07/12] kthread: to_live_kthread() needs try_get_task_stack()

From: Oleg Nesterov get_task_struct(tsk) no longer pins tsk->stack so all users of to_live_kthread() should do try_get_task_stack/put_task_stack to protect "struct kthread" which lives on kthread's stack. TODO: Kill to_live_kthread(), perhaps we can even kill "struct kthread"

[PATCH 07/12] kthread: to_live_kthread() needs try_get_task_stack()

From: Oleg Nesterov get_task_struct(tsk) no longer pins tsk->stack so all users of to_live_kthread() should do try_get_task_stack/put_task_stack to protect "struct kthread" which lives on kthread's stack. TODO: Kill to_live_kthread(), perhaps we can even kill "struct kthread" too, and rework