[PATCH net-next 1/2] net: vlan: Replace BUG() with WARN_ON_ONCE() in vlan_dev_* stubs

[Gal Pressman <gal@nvidia.com>]

When CONFIG_VLAN_8021Q=n, a set of stub helpers are used, three of these
helpers use BUG() unconditionally.

This code should not be reached, as callers of these functions should
always check for is_vlan_dev() first, but the usage of BUG() is not
recommended, replace it with WARN_ON() instead.

This also resolves the following compilation error when:
* CONFIG_VLAN_8021Q=n
* CONFIG_OBJTOOL=y
* CONFIG_OBJTOOL_WERROR=y

drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.o: error: objtool: parse_mirred.isra.0+0x370: mlx5e_tc_act_vlan_add_push_action() missing __noreturn in .c/.h or NORETURN() in noreturns.h

Which is caused by the call to BUG(), which never returns.

Reviewed-by: Alex Lazar <alazar@nvidia.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Gal Pressman <gal@nvidia.com>
---
 include/linux/if_vlan.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index 38456b42cdb5..9135cbe6ae92 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -254,19 +254,19 @@ vlan_for_each(struct net_device *dev,
 
 static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev)
 {
-	BUG();
+	WARN_ON_ONCE(1);
 	return NULL;
 }
 
 static inline u16 vlan_dev_vlan_id(const struct net_device *dev)
 {
-	BUG();
+	WARN_ON_ONCE(1);
 	return 0;
 }
 
 static inline __be16 vlan_dev_vlan_proto(const struct net_device *dev)
 {
-	BUG();
+	WARN_ON_ONCE(1);
 	return 0;
 }
 
-- 
2.40.1