Linux 4.14.95

[thirdparty/kernel/stable-queue.git] / releases / 3.10.67 / revert-swiotlb-xen-pass-dev_addr-to-swiotlb_tbl_unmap_single.patch

From dbdd74763f1faf799fbb9ed30423182e92919378 Mon Sep 17 00:00:00 2001
From: David Vrabel <david.vrabel@citrix.com>
Date: Wed, 10 Dec 2014 14:48:43 +0000
Subject: Revert "swiotlb-xen: pass dev_addr to swiotlb_tbl_unmap_single"

From: David Vrabel <david.vrabel@citrix.com>

commit dbdd74763f1faf799fbb9ed30423182e92919378 upstream.

This reverts commit 2c3fc8d26dd09b9d7069687eead849ee81c78e46.

This commit broke on x86 PV because entries in the generic SWIOTLB are
indexed using (pseudo-)physical address not DMA address and these are
not the same in a x86 PV guest.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/xen/swiotlb-xen.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -390,7 +390,7 @@ static void xen_unmap_single(struct devi
 
 	/* NOTE: We use dev_addr here, not paddr! */
 	if (is_xen_swiotlb_buffer(dev_addr)) {
-		swiotlb_tbl_unmap_single(hwdev, dev_addr, size, dir);
+		swiotlb_tbl_unmap_single(hwdev, paddr, size, dir);
 		return;
 	}