diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 22c6758b01aa690b5027b1ed378a9c0c33bdec86..8c3d7dd91c25c237a5b8fc400bf1f6294adeec1e 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -170,6 +170,13 @@ void __init arm64_memblock_init(void)
 {
 	const s64 linear_region_size = -(s64)PAGE_OFFSET;
 
+	/*
+	 * Ensure that the linear region takes up exactly half of the kernel
+	 * virtual address space. This way, we can distinguish a linear address
+	 * from a kernel/module/vmalloc address by testing a single bit.
+	 */
+	BUILD_BUG_ON(linear_region_size != BIT(VA_BITS - 1));
+
 	/*
 	 * Select a suitable value for the base of physical memory.
 	 */