Need to pass the pointer within the swiotlb internal buffer to the
swiotlb library, that in the case of xen_unmap_single is dev_addr, not
paddr.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: stable@vger.kernel.org
 
        /* NOTE: We use dev_addr here, not paddr! */
        if (is_xen_swiotlb_buffer(dev_addr)) {
-               swiotlb_tbl_unmap_single(hwdev, paddr, size, dir);
+               swiotlb_tbl_unmap_single(hwdev, dev_addr, size, dir);
                return;
        }