Merge branch 'bridge-prepare-lockless-br_port_fill_attrs-i'

Eric Dumazet says:

====================
bridge: prepare lockless br_port_fill_attrs() (I)

medium-term goal is to allow "ip link show" dump commands to run without RTNL.

This round of patches adds/fixes some lockess accesses in bridge.

This is not complete, more patches will come later.

Ultimately all changes to p->flags should use set_bit()/clear_bit().

I repeat (AI agents might read this cover ?):

Many p->flags accesses are racy, and will hopefully be fixed in a
future series.
====================

Link: https://patch.msgid.link/20260604141343.2124500-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 53 insertions, 25 deletions

diff --git a/include/linux/if_bridge.h b/include/linux/if_bridge.h
index ec9ffea1e46e..75673b8bffcb 100644
--- a/include/linux/if_bridge.h
+++ b/include/linux/if_bridge.h
@@ -36,32 +36,60 @@ struct br_ip_list {
 	struct br_ip addr;
 };
 
-#define BR_HAIRPIN_MODE		BIT(0)
-#define BR_BPDU_GUARD		BIT(1)
-#define BR_ROOT_BLOCK		BIT(2)
-#define BR_MULTICAST_FAST_LEAVE	BIT(3)
-#define BR_ADMIN_COST		BIT(4)
-#define BR_LEARNING		BIT(5)
-#define BR_FLOOD		BIT(6)
+enum bridge_flags_bit {
+	BR_HAIRPIN_MODE_BIT,
+	BR_BPDU_GUARD_BIT,
+	BR_ROOT_BLOCK_BIT,
+	BR_MULTICAST_FAST_LEAVE_BIT,
+	BR_ADMIN_COST_BIT,
+	BR_LEARNING_BIT,
+	BR_FLOOD_BIT,
+	BR_PROMISC_BIT,
+	BR_PROXYARP_BIT,
+	BR_LEARNING_SYNC_BIT,
+	BR_PROXYARP_WIFI_BIT,
+	BR_MCAST_FLOOD_BIT,
+	BR_MULTICAST_TO_UNICAST_BIT,
+	BR_VLAN_TUNNEL_BIT,
+	BR_BCAST_FLOOD_BIT,
+	BR_NEIGH_SUPPRESS_BIT,
+	BR_ISOLATED_BIT,
+	BR_MRP_AWARE_BIT,
+	BR_MRP_LOST_CONT_BIT,
+	BR_MRP_LOST_IN_CONT_BIT,
+	BR_TX_FWD_OFFLOAD_BIT,
+	BR_PORT_LOCKED_BIT,
+	BR_PORT_MAB_BIT,
+	BR_NEIGH_VLAN_SUPPRESS_BIT,
+	BR_NEIGH_FORWARD_GRAT_BIT,
+};
+
+#define BR_HAIRPIN_MODE		BIT(BR_HAIRPIN_MODE_BIT)
+#define BR_BPDU_GUARD		BIT(BR_BPDU_GUARD_BIT)
+#define BR_ROOT_BLOCK		BIT(BR_ROOT_BLOCK_BIT)
+#define BR_MULTICAST_FAST_LEAVE	BIT(BR_MULTICAST_FAST_LEAVE_BIT)
+#define BR_ADMIN_COST		BIT(BR_ADMIN_COST_BIT)
+#define BR_LEARNING		BIT(BR_LEARNING_BIT)
+#define BR_FLOOD		BIT(BR_FLOOD_BIT)
 #define BR_AUTO_MASK		(BR_FLOOD | BR_LEARNING)
-#define BR_PROMISC		BIT(7)
-#define BR_PROXYARP		BIT(8)
-#define BR_LEARNING_SYNC	BIT(9)
-#define BR_PROXYARP_WIFI	BIT(10)
-#define BR_MCAST_FLOOD		BIT(11)
-#define BR_MULTICAST_TO_UNICAST	BIT(12)
-#define BR_VLAN_TUNNEL		BIT(13)
-#define BR_BCAST_FLOOD		BIT(14)
-#define BR_NEIGH_SUPPRESS	BIT(15)
-#define BR_ISOLATED		BIT(16)
-#define BR_MRP_AWARE		BIT(17)
-#define BR_MRP_LOST_CONT	BIT(18)
-#define BR_MRP_LOST_IN_CONT	BIT(19)
-#define BR_TX_FWD_OFFLOAD	BIT(20)
-#define BR_PORT_LOCKED		BIT(21)
-#define BR_PORT_MAB		BIT(22)
-#define BR_NEIGH_VLAN_SUPPRESS	BIT(23)
-#define BR_NEIGH_FORWARD_GRAT	BIT(24)
+#define BR_PROMISC		BIT(BR_PROMISC_BIT)
+#define BR_PROXYARP		BIT(BR_PROXYARP_BIT)
+#define BR_LEARNING_SYNC	BIT(BR_LEARNING_SYNC_BIT)
+#define BR_PROXYARP_WIFI	BIT(BR_PROXYARP_WIFI_BIT)
+#define BR_MCAST_FLOOD		BIT(BR_MCAST_FLOOD_BIT)
+#define BR_MULTICAST_TO_UNICAST	BIT(BR_MULTICAST_TO_UNICAST_BIT)
+#define BR_VLAN_TUNNEL		BIT(BR_VLAN_TUNNEL_BIT)
+#define BR_BCAST_FLOOD		BIT(BR_BCAST_FLOOD_BIT)
+#define BR_NEIGH_SUPPRESS	BIT(BR_NEIGH_SUPPRESS_BIT)
+#define BR_ISOLATED		BIT(BR_ISOLATED_BIT)
+#define BR_MRP_AWARE		BIT(BR_MRP_AWARE_BIT)
+#define BR_MRP_LOST_CONT	BIT(BR_MRP_LOST_CONT_BIT)
+#define BR_MRP_LOST_IN_CONT	BIT(BR_MRP_LOST_IN_CONT_BIT)
+#define BR_TX_FWD_OFFLOAD	BIT(BR_TX_FWD_OFFLOAD_BIT)
+#define BR_PORT_LOCKED		BIT(BR_PORT_LOCKED_BIT)
+#define BR_PORT_MAB		BIT(BR_PORT_MAB_BIT)
+#define BR_NEIGH_VLAN_SUPPRESS	BIT(BR_NEIGH_VLAN_SUPPRESS_BIT)
+#define BR_NEIGH_FORWARD_GRAT	BIT(BR_NEIGH_FORWARD_GRAT_BIT)
 
 #define BR_DEFAULT_AGEING_TIME	(300 * HZ)