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diff --git a/include/linux/kho/abi/luo.h b/include/linux/kho/abi/luo.h
new file mode 100644
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+++ b/include/linux/kho/abi/luo.h
@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*
+ * Copyright (c) 2025, Google LLC.
+ * Pasha Tatashin <pasha.tatashin@soleen.com>
+ */
+
+/**
+ * DOC: Live Update Orchestrator ABI
+ *
+ * This header defines the stable Application Binary Interface used by the
+ * Live Update Orchestrator to pass state from a pre-update kernel to a
+ * post-update kernel. The ABI is built upon the Kexec HandOver framework
+ * and uses a Flattened Device Tree to describe the preserved data.
+ *
+ * This interface is a contract. Any modification to the FDT structure, node
+ * properties, compatible strings, or the layout of the `__packed` serialization
+ * structures defined here constitutes a breaking change. Such changes require
+ * incrementing the version number in the relevant `_COMPATIBLE` string to
+ * prevent a new kernel from misinterpreting data from an old kernel.
+ *
+ * Changes are allowed provided the compatibility version is incremented;
+ * however, backward/forward compatibility is only guaranteed for kernels
+ * supporting the same ABI version.
+ *
+ * FDT Structure Overview:
+ *   The entire LUO state is encapsulated within a single KHO entry named "LUO".
+ *   This entry contains an FDT with the following layout:
+ *
+ *   .. code-block:: none
+ *
+ *     / {
+ *         compatible = "luo-v1";
+ *         liveupdate-number = <...>;
+ *     };
+ *
+ * Main LUO Node (/):
+ *
+ *   - compatible: "luo-v1"
+ *     Identifies the overall LUO ABI version.
+ *   - liveupdate-number: u64
+ *     A counter tracking the number of successful live updates performed.
+ */
+
+#ifndef _LINUX_KHO_ABI_LUO_H
+#define _LINUX_KHO_ABI_LUO_H
+
+/*
+ * The LUO FDT hooks all LUO state for sessions, fds, etc.
+ * In the root it also carries "liveupdate-number" 64-bit property that
+ * corresponds to the number of live-updates performed on this machine.
+ */
+#define LUO_FDT_SIZE		PAGE_SIZE
+#define LUO_FDT_KHO_ENTRY_NAME	"LUO"
+#define LUO_FDT_COMPATIBLE	"luo-v1"
+#define LUO_FDT_LIVEUPDATE_NUM	"liveupdate-number"
+
+#endif /* _LINUX_KHO_ABI_LUO_H */