--- zzzz-none-000/linux-4.4.271/arch/arm64/include/asm/thread_info.h	2021-06-03 06:22:09.000000000 +0000
+++ hawkeye-5590-750/linux-4.4.271/arch/arm64/include/asm/thread_info.h	2023-04-19 10:22:27.000000000 +0000
@@ -36,6 +36,7 @@
 
 struct task_struct;
 
+#include <asm/stack_pointer.h>
 #include <asm/types.h>
 
 typedef unsigned long mm_segment_t;
@@ -47,11 +48,22 @@
 struct thread_info {
 	unsigned long		flags;		/* low level flags */
 	mm_segment_t		addr_limit;	/* address limit */
+#ifndef CONFIG_THREAD_INFO_IN_TASK
 	struct task_struct	*task;		/* main task structure */
+#endif
 	int			preempt_count;	/* 0 => preemptable, <0 => bug */
+#ifndef CONFIG_THREAD_INFO_IN_TASK
 	int			cpu;		/* cpu */
+#endif
 };
 
+#ifdef CONFIG_THREAD_INFO_IN_TASK
+#define INIT_THREAD_INFO(tsk)						\
+{									\
+	.preempt_count	= INIT_PREEMPT_COUNT,				\
+	.addr_limit	= KERNEL_DS,					\
+}
+#else
 #define INIT_THREAD_INFO(tsk)						\
 {									\
 	.task		= &tsk,						\
@@ -61,23 +73,26 @@
 }
 
 #define init_thread_info	(init_thread_union.thread_info)
-#define init_stack		(init_thread_union.stack)
-
-/*
- * how to get the current stack pointer from C
- */
-register unsigned long current_stack_pointer asm ("sp");
 
 /*
  * how to get the thread information struct from C
  */
 static inline struct thread_info *current_thread_info(void) __attribute_const__;
 
+/*
+ * struct thread_info can be accessed directly via sp_el0.
+ */
 static inline struct thread_info *current_thread_info(void)
 {
-	return (struct thread_info *)
-		(current_stack_pointer & ~(THREAD_SIZE - 1));
+	unsigned long sp_el0;
+
+	asm ("mrs %0, sp_el0" : "=r" (sp_el0));
+
+	return (struct thread_info *)sp_el0;
 }
+#endif
+
+#define init_stack		(init_thread_union.stack)
 
 #define thread_saved_pc(tsk)	\
 	((unsigned long)(tsk->thread.cpu_context.pc))