--- zzzz-none-000/linux-3.10.107/arch/arm64/lib/Makefile	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/arm64/lib/Makefile	2021-02-04 17:41:59.000000000 +0000
@@ -1,6 +1,18 @@
-lib-y		:= bitops.o delay.o					\
-		   strncpy_from_user.o strnlen_user.o clear_user.o	\
-		   copy_from_user.o copy_to_user.o copy_in_user.o	\
-		   copy_page.o clear_page.o				\
-		   memchr.o memcpy.o memmove.o memset.o			\
+lib-y		:= bitops.o clear_user.o delay.o copy_from_user.o	\
+		   copy_to_user.o copy_in_user.o copy_page.o		\
+		   clear_page.o memchr.o memcpy.o memmove.o memset.o	\
+		   memcmp.o strcmp.o strncmp.o strlen.o strnlen.o	\
 		   strchr.o strrchr.o
+
+# Tell the compiler to treat all general purpose registers as
+# callee-saved, which allows for efficient runtime patching of the bl
+# instruction in the caller with an atomic instruction when supported by
+# the CPU. Result and argument registers are handled correctly, based on
+# the function prototype.
+lib-$(CONFIG_ARM64_LSE_ATOMICS) += atomic_ll_sc.o
+CFLAGS_atomic_ll_sc.o	:= -fcall-used-x0 -ffixed-x1 -ffixed-x2		\
+		   -ffixed-x3 -ffixed-x4 -ffixed-x5 -ffixed-x6		\
+		   -ffixed-x7 -fcall-saved-x8 -fcall-saved-x9		\
+		   -fcall-saved-x10 -fcall-saved-x11 -fcall-saved-x12	\
+		   -fcall-saved-x13 -fcall-saved-x14 -fcall-saved-x15	\
+		   -fcall-saved-x16 -fcall-saved-x17 -fcall-saved-x18