v4.19.13 snapshot.
diff --git a/arch/arm/include/asm/shmparam.h b/arch/arm/include/asm/shmparam.h
new file mode 100644
index 0000000..367a9da
--- /dev/null
+++ b/arch/arm/include/asm/shmparam.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASMARM_SHMPARAM_H
+#define _ASMARM_SHMPARAM_H
+
+/*
+ * This should be the size of the virtually indexed cache/ways,
+ * or page size, whichever is greater since the cache aliases
+ * every size/ways bytes.
+ */
+#define SHMLBA (4 * PAGE_SIZE) /* attach addr a multiple of this */
+
+/*
+ * Enforce SHMLBA in shmat
+ */
+#define __ARCH_FORCE_SHMLBA
+
+#endif /* _ASMARM_SHMPARAM_H */