Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Daniel Borkmann says:

====================
pull-request: bpf 2019-12-19

The following pull-request contains BPF updates for your *net* tree.

We've added 10 non-merge commits during the last 8 day(s) which contain
a total of 21 files changed, 269 insertions(+), 108 deletions(-).

The main changes are:

1) Fix lack of synchronization between xsk wakeup and destroying resources
   used by xsk wakeup, from Maxim Mikityanskiy.

2) Fix pruning with tail call patching, untrack programs in case of verifier
   error and fix a cgroup local storage tracking bug, from Daniel Borkmann.

3) Fix clearing skb->tstamp in bpf_redirect() when going from ingress to
   egress which otherwise cause issues e.g. on fq qdisc, from Lorenz Bauer.

4) Fix compile warning of unused proc_dointvec_minmax_bpf_restricted() when
   only cBPF is present, from Alexander Lobakin.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/intel/i40e/i40e.h

@@ -1152,7 +1152,7 @@ void i40e_set_fec_in_flags(u8 fec_cfg, u32 *flags);
 
 static inline bool i40e_enabled_xdp_vsi(struct i40e_vsi *vsi)
 {
-	return !!vsi->xdp_prog;
+	return !!READ_ONCE(vsi->xdp_prog);
 }
 
 int i40e_create_queue_channel(struct i40e_vsi *vsi, struct i40e_channel *ch);

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

@@ -6823,8 +6823,8 @@ void i40e_down(struct i40e_vsi *vsi)
 	for (i = 0; i < vsi->num_queue_pairs; i++) {
 		i40e_clean_tx_ring(vsi->tx_rings[i]);
 		if (i40e_enabled_xdp_vsi(vsi)) {
-			/* Make sure that in-progress ndo_xdp_xmit
-			 * calls are completed.
+			/* Make sure that in-progress ndo_xdp_xmit and
+			 * ndo_xsk_wakeup calls are completed.
 			 */
 			synchronize_rcu();
 			i40e_clean_tx_ring(vsi->xdp_rings[i]);
@@ -12546,8 +12546,12 @@ static int i40e_xdp_setup(struct i40e_vsi *vsi,
 
 	old_prog = xchg(&vsi->xdp_prog, prog);
 
-	if (need_reset)
+	if (need_reset) {
+		if (!prog)
+			/* Wait until ndo_xsk_wakeup completes. */
+			synchronize_rcu();
 		i40e_reset_and_rebuild(pf, true, true);
+	}
 
 	for (i = 0; i < vsi->num_queue_pairs; i++)
 		WRITE_ONCE(vsi->rx_rings[i]->xdp_prog, vsi->xdp_prog);

drivers/net/ethernet/intel/i40e/i40e_xsk.c

@@ -787,8 +787,12 @@ int i40e_xsk_wakeup(struct net_device *dev, u32 queue_id, u32 flags)
 {
 	struct i40e_netdev_priv *np = netdev_priv(dev);
 	struct i40e_vsi *vsi = np->vsi;
+	struct i40e_pf *pf = vsi->back;
 	struct i40e_ring *ring;
 
+	if (test_bit(__I40E_CONFIG_BUSY, pf->state))
+		return -ENETDOWN;
+
 	if (test_bit(__I40E_VSI_DOWN, vsi->state))
 		return -ENETDOWN;
 

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c

@@ -10261,7 +10261,12 @@ static int ixgbe_xdp_setup(struct net_device *dev, struct bpf_prog *prog)
 
 	/* If transitioning XDP modes reconfigure rings */
 	if (need_reset) {
-		int err = ixgbe_setup_tc(dev, adapter->hw_tcs);
+		int err;
+
+		if (!prog)
+			/* Wait until ndo_xsk_wakeup completes. */
+			synchronize_rcu();
+		err = ixgbe_setup_tc(dev, adapter->hw_tcs);
 
 		if (err) {
 			rcu_assign_pointer(adapter->xdp_prog, old_prog);

drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c

@@ -709,10 +709,14 @@ int ixgbe_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags)
 	if (qid >= adapter->num_xdp_queues)
 		return -ENXIO;
 
-	if (!adapter->xdp_ring[qid]->xsk_umem)
+	ring = adapter->xdp_ring[qid];
+
+	if (test_bit(__IXGBE_TX_DISABLED, &ring->state))
+		return -ENETDOWN;
+
+	if (!ring->xsk_umem)
 		return -ENXIO;
 
-	ring = adapter->xdp_ring[qid];
 	if (!napi_if_scheduled_mark_missed(&ring->q_vector->napi)) {
 		u64 eics = BIT_ULL(ring->q_vector->v_idx);
 

drivers/net/ethernet/mellanox/mlx5/core/en.h

@@ -760,7 +760,7 @@ enum {
 	MLX5E_STATE_OPENED,
 	MLX5E_STATE_DESTROYING,
 	MLX5E_STATE_XDP_TX_ENABLED,
-	MLX5E_STATE_XDP_OPEN,
+	MLX5E_STATE_XDP_ACTIVE,
 };
 
 struct mlx5e_rqt {

drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h

@@ -75,12 +75,18 @@ int mlx5e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
 static inline void mlx5e_xdp_tx_enable(struct mlx5e_priv *priv)
 {
 	set_bit(MLX5E_STATE_XDP_TX_ENABLED, &priv->state);
+
+	if (priv->channels.params.xdp_prog)
+		set_bit(MLX5E_STATE_XDP_ACTIVE, &priv->state);
 }
 
 static inline void mlx5e_xdp_tx_disable(struct mlx5e_priv *priv)
 {
+	if (priv->channels.params.xdp_prog)
+		clear_bit(MLX5E_STATE_XDP_ACTIVE, &priv->state);
+
 	clear_bit(MLX5E_STATE_XDP_TX_ENABLED, &priv->state);
-	/* let other device's napi(s) see our new state */
+	/* Let other device's napi(s) and XSK wakeups see our new state. */
 	synchronize_rcu();
 }
 
@@ -89,19 +95,9 @@ static inline bool mlx5e_xdp_tx_is_enabled(struct mlx5e_priv *priv)
 	return test_bit(MLX5E_STATE_XDP_TX_ENABLED, &priv->state);
 }
 
-static inline void mlx5e_xdp_set_open(struct mlx5e_priv *priv)
+static inline bool mlx5e_xdp_is_active(struct mlx5e_priv *priv)
 {
-	set_bit(MLX5E_STATE_XDP_OPEN, &priv->state);
-}
-
-static inline void mlx5e_xdp_set_closed(struct mlx5e_priv *priv)
-{
-	clear_bit(MLX5E_STATE_XDP_OPEN, &priv->state);
-}
-
-static inline bool mlx5e_xdp_is_open(struct mlx5e_priv *priv)
-{
-	return test_bit(MLX5E_STATE_XDP_OPEN, &priv->state);
+	return test_bit(MLX5E_STATE_XDP_ACTIVE, &priv->state);
 }
 
 static inline void mlx5e_xmit_xdp_doorbell(struct mlx5e_xdpsq *sq)

drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c

@@ -144,6 +144,7 @@ void mlx5e_close_xsk(struct mlx5e_channel *c)
 {
 	clear_bit(MLX5E_CHANNEL_STATE_XSK, c->state);
 	napi_synchronize(&c->napi);
+	synchronize_rcu(); /* Sync with the XSK wakeup. */
 
 	mlx5e_close_rq(&c->xskrq);
 	mlx5e_close_cq(&c->xskrq.cq);

drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c

@@ -14,7 +14,7 @@ int mlx5e_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags)
 	struct mlx5e_channel *c;
 	u16 ix;
 
-	if (unlikely(!mlx5e_xdp_is_open(priv)))
+	if (unlikely(!mlx5e_xdp_is_active(priv)))
 		return -ENETDOWN;
 
 	if (unlikely(!mlx5e_qid_get_ch_if_in_group(params, qid, MLX5E_RQ_GROUP_XSK, &ix)))

drivers/net/ethernet/mellanox/mlx5/core/en_main.c

@@ -3000,12 +3000,9 @@ void mlx5e_timestamp_init(struct mlx5e_priv *priv)
 int mlx5e_open_locked(struct net_device *netdev)
 {
 	struct mlx5e_priv *priv = netdev_priv(netdev);
-	bool is_xdp = priv->channels.params.xdp_prog;
 	int err;
 
 	set_bit(MLX5E_STATE_OPENED, &priv->state);
-	if (is_xdp)
-		mlx5e_xdp_set_open(priv);
 
 	err = mlx5e_open_channels(priv, &priv->channels);
 	if (err)
@@ -3020,8 +3017,6 @@ int mlx5e_open_locked(struct net_device *netdev)
 	return 0;
 
 err_clear_state_opened_flag:
-	if (is_xdp)
-		mlx5e_xdp_set_closed(priv);
 	clear_bit(MLX5E_STATE_OPENED, &priv->state);
 	return err;
 }
@@ -3053,8 +3048,6 @@ int mlx5e_close_locked(struct net_device *netdev)
 	if (!test_bit(MLX5E_STATE_OPENED, &priv->state))
 		return 0;
 
-	if (priv->channels.params.xdp_prog)
-		mlx5e_xdp_set_closed(priv);
 	clear_bit(MLX5E_STATE_OPENED, &priv->state);
 
 	netif_carrier_off(priv->netdev);
@@ -4371,16 +4364,6 @@ static int mlx5e_xdp_allowed(struct mlx5e_priv *priv, struct bpf_prog *prog)
 	return 0;
 }
 
-static int mlx5e_xdp_update_state(struct mlx5e_priv *priv)
-{
-	if (priv->channels.params.xdp_prog)
-		mlx5e_xdp_set_open(priv);
-	else
-		mlx5e_xdp_set_closed(priv);
-
-	return 0;
-}
-
 static int mlx5e_xdp_set(struct net_device *netdev, struct bpf_prog *prog)
 {
 	struct mlx5e_priv *priv = netdev_priv(netdev);
@@ -4415,7 +4398,7 @@ static int mlx5e_xdp_set(struct net_device *netdev, struct bpf_prog *prog)
 		mlx5e_set_rq_type(priv->mdev, &new_channels.params);
 		old_prog = priv->channels.params.xdp_prog;
 
-		err = mlx5e_safe_switch_channels(priv, &new_channels, mlx5e_xdp_update_state);
+		err = mlx5e_safe_switch_channels(priv, &new_channels, NULL);
 		if (err)
 			goto unlock;
 	} else {