diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c
index 32e0771d6477..e212270d4e09 100644
--- a/arch/arm64/mm/mmap.c
+++ b/arch/arm64/mm/mmap.c
@@ -61,7 +61,9 @@ int valid_phys_addr_range(phys_addr_t addr, size_t size)
  */
 int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
 {
-	return !(((pfn << PAGE_SHIFT) + size) & ~PHYS_MASK);
+	const phys_addr_t limit = PHYS_MASK + 1;
+
+	return size <= limit && pfn <= (limit - size) >> PAGE_SHIFT;
 }
 
 static int __init adjust_protection_map(void)