diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
index 3beb6a862e80..22ae7babf46b 100644
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -276,12 +276,14 @@ static int usbdev_mmap(struct file *file, struct vm_area_struct *vma)
 		if (remap_pfn_range(vma, vma->vm_start,
 				    virt_to_phys(usbm->mem) >> PAGE_SHIFT,
 				    size, vma->vm_page_prot) < 0) {
+			pr_info("==> if* vma_use_count %d\n", usbm->vma_use_count);
 			dec_usb_memory_use_count(usbm, &usbm->vma_use_count);
 			return -EAGAIN;
 		}
 	} else {
 		if (dma_mmap_coherent(hcd->self.sysdev, vma, mem, dma_handle,
 				      size)) {
+			pr_info("==> else* vma_use_count %d\n", usbm->vma_use_count);
 			dec_usb_memory_use_count(usbm, &usbm->vma_use_count);
 			return -EAGAIN;
 		}