diff --git a/mm/cma.c b/mm/cma.c
index 5aa1a6f74dec..62a5dccc3fb8 100644
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -245,6 +245,9 @@ int __init cma_declare_contiguous(phys_addr_t base,
 	size = ALIGN(size, alignment);
 	limit &= ~(alignment - 1);
 
+	if (!base)
+		fixed = false;
+
 	/* size should be aligned with order_per_bit */
 	if (!IS_ALIGNED(size >> PAGE_SHIFT, 1 << order_per_bit))
 		return -EINVAL;
@@ -268,7 +271,7 @@ int __init cma_declare_contiguous(phys_addr_t base,
 	}
 
 	/* Reserve memory */
-	if (base && fixed) {
+	if (fixed) {
 		if (memblock_is_region_reserved(base, size) ||
 		    memblock_reserve(base, size) < 0) {
 			ret = -EBUSY;