1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index db516c90a977..23c24fe98c00 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -37,7 +37,6 @@
 #include <linux/vfio.h>
 #include <linux/workqueue.h>
 #include <linux/notifier.h>
-#include <linux/dma-iommu.h>
 #include <linux/irqdomain.h>
 #include "vfio.h"
 
@@ -558,6 +557,18 @@ static int vaddr_get_pfns(struct mm_struct *mm, unsigned long vaddr,
 	ret = pin_user_pages_remote(mm, vaddr, npages, flags | FOLL_LONGTERM,
 				    pages, NULL, NULL);
 	if (ret > 0) {
+		int i;
+
+		/*
+		 * The zero page is always resident, we don't need to pin it
+		 * and it falls into our invalid/reserved test so we don't
+		 * unpin in put_pfn().  Unpin all zero pages in the batch here.
+		 */
+		for (i = 0 ; i < ret; i++) {
+			if (unlikely(is_zero_pfn(page_to_pfn(pages[i]))))
+				unpin_user_page(pages[i]);
+		}
+
 		*pfn = page_to_pfn(pages[0]);
 		goto done;
 	}