diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 13ba533f462b..bf5379135e39 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -176,7 +176,7 @@ void __init setup_bootmem(void)
 	 * Make sure that any memory beyond mem_start + (-PAGE_OFFSET) is removed
 	 * as it is unusable by kernel.
 	 */
-	memblock_enforce_memory_limit(mem_start - PAGE_OFFSET);
+	memblock_enforce_memory_limit(-PAGE_OFFSET);
 
 	/* Reserve from the start of the kernel to the end of the kernel */
 	memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);