diff --git a/stand/libsa/zfs/spl/sys/blake3.h b/stand/libsa/zfs/spl/sys/blake3.h
new file mode 100644
index 000000000000..aa2d3b7e55cc
--- /dev/null
+++ b/stand/libsa/zfs/spl/sys/blake3.h
@@ -0,0 +1,17 @@
+/*
+ * Copyright 2022, Netflix, Inc
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+/*
+ * Gross and ugly hack to cope with upstream's sys/blake3.h not being standalone
+ * safe.
+ */
+#define _KERNEL
+
+#include_next <sys/blake3.h>
+
+#undef _KERNEL