From 55131dec2b1c7417d216f861ea7a29dc7c4d2d20 Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Tue, 1 Oct 2019 10:33:51 +0200 Subject: [PATCH] net: socionext: netsec: always grab descriptor lock MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Always acquire tx descriptor spinlock even if a xdp program is not loaded on the netsec device since ndo_xdp_xmit can run concurrently with netsec_netdev_start_xmit and netsec_clean_tx_dring. This can happen loading a xdp program on a different device (e.g virtio-net) and xdp_do_redirect_map/xdp_do_redirect_slow can redirect to netsec even if we do not have a xdp program on it. Fixes: ba2b232108d3 ("net: netsec: add XDP support") Tested-by: Ilias Apalodimas Signed-off-by: Lorenzo Bianconi Reviewed-by: Ilias Apalodimas Acked-by: Toke Høiland-Jørgensen Signed-off-by: David S. Miller --- drivers/net/ethernet/socionext/netsec.c | 30 ++++++------------------- 1 file changed, 7 insertions(+), 23 deletions(-) diff --git a/drivers/net/ethernet/socionext/netsec.c b/drivers/net/ethernet/socionext/netsec.c index 55db7fbd43cc..f9e6744d8fd6 100644 --- a/drivers/net/ethernet/socionext/netsec.c +++ b/drivers/net/ethernet/socionext/netsec.c @@ -282,7 +282,6 @@ struct netsec_desc_ring { void *vaddr; u16 head, tail; u16 xdp_xmit; /* netsec_xdp_xmit packets */ - bool is_xdp; struct page_pool *page_pool; struct xdp_rxq_info xdp_rxq; spinlock_t lock; /* XDP tx queue locking */ @@ -634,8 +633,7 @@ static bool netsec_clean_tx_dring(struct netsec_priv *priv) unsigned int bytes; int cnt = 0; - if (dring->is_xdp) - spin_lock(&dring->lock); + spin_lock(&dring->lock); bytes = 0; entry = dring->vaddr + DESC_SZ * tail; @@ -682,8 +680,8 @@ next: entry = dring->vaddr + DESC_SZ * tail; cnt++; } - if (dring->is_xdp) - spin_unlock(&dring->lock); + + spin_unlock(&dring->lock); if (!cnt) return false; @@ -799,9 +797,6 @@ static void netsec_set_tx_de(struct netsec_priv *priv, de->data_buf_addr_lw = lower_32_bits(desc->dma_addr); de->buf_len_info = (tx_ctrl->tcp_seg_len << 16) | desc->len; de->attr = attr; - /* under spin_lock if using XDP */ - if (!dring->is_xdp) - dma_wmb(); dring->desc[idx] = *desc; if (desc->buf_type == TYPE_NETSEC_SKB) @@ -1123,12 +1118,10 @@ static netdev_tx_t netsec_netdev_start_xmit(struct sk_buff *skb, u16 tso_seg_len = 0; int filled; - if (dring->is_xdp) - spin_lock_bh(&dring->lock); + spin_lock_bh(&dring->lock); filled = netsec_desc_used(dring); if (netsec_check_stop_tx(priv, filled)) { - if (dring->is_xdp) - spin_unlock_bh(&dring->lock); + spin_unlock_bh(&dring->lock); net_warn_ratelimited("%s %s Tx queue full\n", dev_name(priv->dev), ndev->name); return NETDEV_TX_BUSY; @@ -1161,8 +1154,7 @@ static netdev_tx_t netsec_netdev_start_xmit(struct sk_buff *skb, tx_desc.dma_addr = dma_map_single(priv->dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE); if (dma_mapping_error(priv->dev, tx_desc.dma_addr)) { - if (dring->is_xdp) - spin_unlock_bh(&dring->lock); + spin_unlock_bh(&dring->lock); netif_err(priv, drv, priv->ndev, "%s: DMA mapping failed\n", __func__); ndev->stats.tx_dropped++; @@ -1177,8 +1169,7 @@ static netdev_tx_t netsec_netdev_start_xmit(struct sk_buff *skb, netdev_sent_queue(priv->ndev, skb->len); netsec_set_tx_de(priv, dring, &tx_ctrl, &tx_desc, skb); - if (dring->is_xdp) - spin_unlock_bh(&dring->lock); + spin_unlock_bh(&dring->lock); netsec_write(priv, NETSEC_REG_NRM_TX_PKTCNT, 1); /* submit another tx */ return NETDEV_TX_OK; @@ -1262,7 +1253,6 @@ err: static void netsec_setup_tx_dring(struct netsec_priv *priv) { struct netsec_desc_ring *dring = &priv->desc_ring[NETSEC_RING_TX]; - struct bpf_prog *xdp_prog = READ_ONCE(priv->xdp_prog); int i; for (i = 0; i < DESC_NUM; i++) { @@ -1275,12 +1265,6 @@ static void netsec_setup_tx_dring(struct netsec_priv *priv) */ de->attr = 1U << NETSEC_TX_SHIFT_OWN_FIELD; } - - if (xdp_prog) - dring->is_xdp = true; - else - dring->is_xdp = false; - } static int netsec_setup_rx_dring(struct netsec_priv *priv)