diff --git a/mm/cma.c b/mm/cma.c
index 126a6d3bdc9b..6d347864693a 100644
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -44,6 +44,7 @@
 
 struct cma cma_areas[MAX_CMA_AREAS];
 unsigned cma_area_count;
+static DEFINE_MUTEX(cma_mutex);
 
 phys_addr_t cma_get_base(const struct cma *cma)
 {
@@ -508,7 +509,9 @@ struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align,
 		mutex_unlock(&cma->lock);
 
 		pfn = cma->base_pfn + (bitmap_no << cma->order_per_bit);
+		mutex_lock(&cma_mutex);
 		ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA, gfp_mask, &info);
+		mutex_unlock(&cma_mutex);
 		cma_info.nr_migrated += info.nr_migrated;
 		cma_info.nr_reclaimed += info.nr_reclaimed;
 		cma_info.nr_mapped += info.nr_mapped;