xen-netback: fix error handling output

The connect function prints an unintialized error code after an
earlier initialization was removed:

drivers/net/xen-netback/xenbus.c: In function 'connect':
drivers/net/xen-netback/xenbus.c:938:3: error: 'err' may be used uninitialized in this function [-Werror=maybe-uninitialized]

This prints it as -EINVAL instead, which seems to be the most
appropriate error code. Before the patch that caused the warning,
this would print a positive number returned by vsscanf() instead,
which is also wrong. We probably don't need a backport though,
as fixing the warning here should be sufficient.

Fixes: f95842e7a9f2 ("xen: make use of xenbus_read_unsigned() in xen-netback")
Fixes: 8d3d53b3e433 ("xen-netback: Add support for multiple queues")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
OraBug: 25497392

(cherry picked from commit 0f06ac3b6616b9793b3fb5c398d94044a0423492)
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c
index 908411797097c19fda1cff54829c02fbbfdb5a55..961a3470084ba092b036e6053a38fc96f83a6aa0 100644 (file)
--- a/drivers/net/xen-netback/xenbus.c
+++ b/drivers/net/xen-netback/xenbus.c
@@ -849,7 +849,7 @@ static void connect(struct backend_info *be)
                                        "multi-queue-num-queues", 1);
        if (requested_num_queues > xenvif_max_queues) {
                /* buggy or malicious guest */
-               xenbus_dev_fatal(dev, err,
+               xenbus_dev_fatal(dev, -EINVAL,
                                 "guest requested %u queues, exceeding the maximum of %u.",
                                 requested_num_queues, xenvif_max_queues);
                return;