diff --git a/sys/arm64/include/asm.h b/sys/arm64/include/asm.h
--- a/sys/arm64/include/asm.h
+++ b/sys/arm64/include/asm.h
@@ -142,6 +142,58 @@
 #define	BTI_J
 #endif
 
+/*
+ * GNU_PROPERTY_AARCH64_FEATURE_1_NOTE can be used to insert a note that
+ * the current assembly file is built with Pointer Authentication (PAC) or
+ * Branch Target Identification support (BTI). As the linker requires all
+ * object files in an executable or library to have the GNU property
+ * note to emit it in the created elf file we need to add a note to all
+ * assembly files that support BTI so the kernel and dynamic linker can
+ * mark memory used by the file as guarded.
+ *
+ * The GNU_PROPERTY_AARCH64_FEATURE_1_VAL macro encodes the combination
+ * of PAC and BTI that have been enabled. It can be used as follows:
+ * GNU_PROPERTY_AARCH64_FEATURE_1_NOTE(GNU_PROPERTY_AARCH64_FEATURE_1_VAL);
+ *
+ * To use this you need to include <sys/elf_common.h> for
+ * GNU_PROPERTY_AARCH64_FEATURE_1_*
+ */
+#if defined(__ARM_FEATURE_BTI_DEFAULT)
+#if defined(__ARM_FEATURE_PAC_DEFAULT)
+/* BTI, PAC */
+#define	GNU_PROPERTY_AARCH64_FEATURE_1_VAL				\
+    (GNU_PROPERTY_AARCH64_FEATURE_1_BTI | GNU_PROPERTY_AARCH64_FEATURE_1_PAC)
+#else
+/* BTI, no PAC */
+#define	GNU_PROPERTY_AARCH64_FEATURE_1_VAL				\
+    (GNU_PROPERTY_AARCH64_FEATURE_1_BTI)
+#endif
+#elif defined(__ARM_FEATURE_PAC_DEFAULT)
+/* No BTI, PAC */
+#define	GNU_PROPERTY_AARCH64_FEATURE_1_VAL				\
+    (GNU_PROPERTY_AARCH64_FEATURE_1_PAC)
+#else
+/* No BTI, no PAC */
+#define	GNU_PROPERTY_AARCH64_FEATURE_1_VAL	0
+#endif
+
+#if defined(__ARM_FEATURE_BTI_DEFAULT) || defined(__ARM_FEATURE_PAC_DEFAULT)
+#define	GNU_PROPERTY_AARCH64_FEATURE_1_NOTE(x)				\
+    .section .note.gnu.property, "a";					\
+    .balign 8;								\
+    .4byte 0x4;				/* sizeof(vendor) */		\
+    .4byte 0x10;			/* sizeof(note data) */		\
+    .4byte (NT_GNU_PROPERTY_TYPE_0);					\
+    .asciz "GNU";			/* vendor */			\
+    /* note data: */							\
+    .4byte (GNU_PROPERTY_AARCH64_FEATURE_1_AND);			\
+    .4byte 0x4;				/* sizeof(property) */		\
+    .4byte (x);				/* property */			\
+    .4byte 0
+#else
+#define	GNU_PROPERTY_AARCH64_FEATURE_1_NOTE(x)
+#endif
+
 #endif /* _MACHINE_ASM_H_ */
 
 #endif /* !__arm__ */