diff --git a/sys/arm64/arm64/identcpu.c b/sys/arm64/arm64/identcpu.c
--- a/sys/arm64/arm64/identcpu.c
+++ b/sys/arm64/arm64/identcpu.c
@@ -2496,23 +2496,6 @@
 	return (a - b);
 }
 
-bool
-extract_user_id_field(u_int reg, u_int field_shift, uint8_t *val)
-{
-	uint64_t value;
-	int i;
-
-	for (i = 0; i < nitems(user_regs); i++) {
-		if (user_regs[i].reg == reg) {
-			value = CPU_DESC_FIELD(user_cpu_desc, i);
-			*val = value >> field_shift;
-			return (true);
-		}
-	}
-
-	return (false);
-}
-
 bool
 get_kernel_reg(u_int reg, uint64_t *val)
 {
diff --git a/sys/arm64/include/cpu.h b/sys/arm64/include/cpu.h
--- a/sys/arm64/include/cpu.h
+++ b/sys/arm64/include/cpu.h
@@ -233,7 +233,6 @@
 /* Functions to read the sanitised view of the special registers */
 void	update_special_regs(u_int);
 void	update_special_reg(u_int reg, uint64_t, uint64_t);
-bool	extract_user_id_field(u_int, u_int, uint8_t *);
 bool	get_kernel_reg(u_int, uint64_t *);
 bool	get_kernel_reg_masked(u_int, uint64_t *, uint64_t);
 bool	get_user_reg(u_int, uint64_t *, bool);