i40e: allocate memory safer

BugLink: http://bugs.launchpad.net/bugs/1547674

The sync_vsi_filter function was allocating memory in such
a way that it could sleep (GFP_KERNEL) which was causing a problem
when called by the team driver under rcu_read_lock(), which cannot
be held while sleeping.  Found with lockdep.

Change-ID: I4e59053cb5eedcf3d0ca151715be3dc42a94bdd5
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
(cherry picked from net-next commit 38c3cec7)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

drivers/net/ethernet/intel/i40e/i40e_main.c

@@ -1937,7 +1937,7 @@ int i40e_sync_vsi_filters(struct i40e_vsi *vsi)
 			    sizeof(struct i40e_aqc_remove_macvlan_element_data);
 		del_list_size = filter_list_len *
 			    sizeof(struct i40e_aqc_remove_macvlan_element_data);
-		del_list = kzalloc(del_list_size, GFP_KERNEL);
+		del_list = kzalloc(del_list_size, GFP_ATOMIC);
 		if (!del_list) {
 			i40e_cleanup_add_list(&tmp_add_list);
 
@@ -2015,7 +2015,7 @@ int i40e_sync_vsi_filters(struct i40e_vsi *vsi)
 			       sizeof(struct i40e_aqc_add_macvlan_element_data),
 		add_list_size = filter_list_len *
 			       sizeof(struct i40e_aqc_add_macvlan_element_data);
-		add_list = kzalloc(add_list_size, GFP_KERNEL);
+		add_list = kzalloc(add_list_size, GFP_ATOMIC);
 		if (!add_list) {
 			/* Purge element from temporary lists */
 			i40e_cleanup_add_list(&tmp_add_list);