xen-netback: don't "handle" error by BUG()

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 <jbeulich@suse.com>
Cc: stable@vger.kernel.org
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
index b8100298017b9ac4a7cfb44452d49c7e5136ab58..fcaf4dd9d9c4c7de291861d0a741a371563df97e 100644 (file)
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -1328,13 +1328,11 @@ int xenvif_tx_action(struct xenvif_queue *queue, int budget)
                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);