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-rw-r--r--arch/arm64/lib/Makefile21
-rw-r--r--arch/arm64/lib/atomic_ll_sc.c3
-rw-r--r--arch/arm64/lib/error-inject.c18
3 files changed, 20 insertions, 22 deletions
diff --git a/arch/arm64/lib/Makefile b/arch/arm64/lib/Makefile
index 33c2a4abda04..c21b936dc01d 100644
--- a/arch/arm64/lib/Makefile
+++ b/arch/arm64/lib/Makefile
@@ -11,25 +11,8 @@ CFLAGS_REMOVE_xor-neon.o += -mgeneral-regs-only
CFLAGS_xor-neon.o += -ffreestanding
endif
-# Tell the compiler to treat all general purpose registers (with the
-# exception of the IP registers, which are already handled by the caller
-# in case of a PLT) 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 := -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-x18 -fomit-frame-pointer
-CFLAGS_REMOVE_atomic_ll_sc.o := $(CC_FLAGS_FTRACE)
-GCOV_PROFILE_atomic_ll_sc.o := n
-KASAN_SANITIZE_atomic_ll_sc.o := n
-KCOV_INSTRUMENT_atomic_ll_sc.o := n
-UBSAN_SANITIZE_atomic_ll_sc.o := n
-
lib-$(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) += uaccess_flushcache.o
obj-$(CONFIG_CRC32) += crc32.o
+
+obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o
diff --git a/arch/arm64/lib/atomic_ll_sc.c b/arch/arm64/lib/atomic_ll_sc.c
deleted file mode 100644
index b0c538b0da28..000000000000
--- a/arch/arm64/lib/atomic_ll_sc.c
+++ /dev/null
@@ -1,3 +0,0 @@
-#include <asm/atomic.h>
-#define __ARM64_IN_ATOMIC_IMPL
-#include <asm/atomic_ll_sc.h>
diff --git a/arch/arm64/lib/error-inject.c b/arch/arm64/lib/error-inject.c
new file mode 100644
index 000000000000..ed15021da3ed
--- /dev/null
+++ b/arch/arm64/lib/error-inject.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/error-injection.h>
+#include <linux/kprobes.h>
+
+void override_function_with_return(struct pt_regs *regs)
+{
+ /*
+ * 'regs' represents the state on entry of a predefined function in
+ * the kernel/module and which is captured on a kprobe.
+ *
+ * When kprobe returns back from exception it will override the end
+ * of probed function and directly return to the predefined
+ * function's caller.
+ */
+ instruction_pointer_set(regs, procedure_link_pointer(regs));
+}
+NOKPROBE_SYMBOL(override_function_with_return);