diff --git a/config/kernel-super-userns.m4 b/config/kernel-super-userns.m4
deleted file mode 100644
index 1ad35f2d1..000000000
--- a/config/kernel-super-userns.m4
+++ /dev/null
@@ -1,25 +0,0 @@
-dnl #
-dnl # 4.8 API change
-dnl # struct user_namespace was added to struct super_block as
-dnl # super->s_user_ns member
-dnl #
-AC_DEFUN([ZFS_AC_KERNEL_SRC_SUPER_USER_NS], [
-	ZFS_LINUX_TEST_SRC([super_user_ns], [
-		#include <linux/fs.h>
-		#include <linux/user_namespace.h>
-	], [
-		struct super_block super;
-		super.s_user_ns = (struct user_namespace *)NULL;
-	])
-])
-
-AC_DEFUN([ZFS_AC_KERNEL_SUPER_USER_NS], [
-	AC_MSG_CHECKING([whether super_block->s_user_ns exists])
-	ZFS_LINUX_TEST_RESULT([super_user_ns], [
-		AC_MSG_RESULT(yes)
-		AC_DEFINE(HAVE_SUPER_USER_NS, 1,
-		    [super_block->s_user_ns exists])
-	],[
-		AC_MSG_RESULT(no)
-	])
-])
diff --git a/config/kernel.m4 b/config/kernel.m4
index d6a198f6c..f9777a8dc 100644
--- a/config/kernel.m4
+++ b/config/kernel.m4
@@ -53,7 +53,6 @@ AC_DEFUN([ZFS_AC_KERNEL_TEST_SRC], [
 	ZFS_AC_KERNEL_SRC_INODE_TIMES
 	ZFS_AC_KERNEL_SRC_RW
 	ZFS_AC_KERNEL_SRC_TIMER_SETUP
-	ZFS_AC_KERNEL_SRC_SUPER_USER_NS
 	ZFS_AC_KERNEL_SRC_PROC_OPERATIONS
 	ZFS_AC_KERNEL_SRC_BLOCK_DEVICE_OPERATIONS
 	ZFS_AC_KERNEL_SRC_BIO
@@ -183,7 +182,6 @@ AC_DEFUN([ZFS_AC_KERNEL_TEST_RESULT], [
 	ZFS_AC_KERNEL_INODE_TIMES
 	ZFS_AC_KERNEL_RW
 	ZFS_AC_KERNEL_TIMER_SETUP
-	ZFS_AC_KERNEL_SUPER_USER_NS
 	ZFS_AC_KERNEL_PROC_OPERATIONS
 	ZFS_AC_KERNEL_BLOCK_DEVICE_OPERATIONS
 	ZFS_AC_KERNEL_BIO
diff --git a/include/os/linux/spl/sys/cred.h b/include/os/linux/spl/sys/cred.h
index c19c3c071..1c5120c24 100644
--- a/include/os/linux/spl/sys/cred.h
+++ b/include/os/linux/spl/sys/cred.h
@@ -63,11 +63,7 @@ zfs_is_init_userns(struct user_namespace *user_ns)
 
 static inline struct user_namespace *zfs_i_user_ns(struct inode *inode)
 {
-#ifdef HAVE_SUPER_USER_NS
 	return (inode->i_sb->s_user_ns);
-#else
-	return (kcred->user_ns);
-#endif
 }
 
 static inline boolean_t zfs_no_idmapping(struct user_namespace *mnt_userns,