[PATCH 5.4 10/13] xen-netback: dont "handle" error by BUG()

[Greg Kroah-Hartman]

From: Jan Beulich <jbeul...@suse.com>

commit 3194a1746e8aabe86075fd3c5e7cf1f4632d7f16 upstream.

In particular -ENOMEM may come back here, from set_foreign_p2m_mapping().
Don't make problems worse, the more that handling elsewhere (together
with map's status fields now indicating whether a mapping wasn't even
attempted, and hence has to be considered failed) doesn't require this
odd way of dealing with errors.

This is part of XSA-362.

Signed-off-by: Jan Beulich <jbeul...@suse.com>
Cc: sta...@vger.kernel.org
Reviewed-by: Juergen Gross <jgr...@suse.com>
Signed-off-by: Juergen Gross <jgr...@suse.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/net/xen-netback/netback.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -1335,13 +1335,11 @@ int xenvif_tx_action(struct xenvif_queue
                return 0;
 
        gnttab_batch_copy(queue->tx_copy_ops, nr_cops);
-       if (nr_mops != 0) {
+       if (nr_mops != 0)
                ret = gnttab_map_refs(queue->tx_map_ops,
                                      NULL,
                                      queue->pages_to_map,
                                      nr_mops);
-               BUG_ON(ret);
-       }
 
        work_done = xenvif_tx_submit(queue);