diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 4d7bef50ab53..0d2df7690238 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -125,10 +125,12 @@ struct netfront_queue { struct sk_buff *tx_skbs[NET_TX_RING_SIZE]; unsigned short tx_link[NET_TX_RING_SIZE]; #define TX_LINK_NONE 0xffff +#define TX_PENDING 0xfffe grant_ref_t gref_tx_head; grant_ref_t grant_tx_ref[NET_TX_RING_SIZE]; struct page *grant_tx_page[NET_TX_RING_SIZE]; unsigned tx_skb_freelist; + unsigned int tx_pend_queue; spinlock_t rx_lock ____cacheline_aligned_in_smp; struct xen_netif_rx_front_ring rx; @@ -154,6 +156,9 @@ struct netfront_info { struct netfront_stats __percpu *rx_stats; struct netfront_stats __percpu *tx_stats; + /* Is device behaving sane? */ + bool broken; + atomic_t rx_gso_checksum_fixup; }; @@ -338,7 +343,7 @@ static int xennet_open(struct net_device *dev) unsigned int i = 0; struct netfront_queue *queue = NULL; - if (!np->queues) + if (!np->queues || np->broken) return -ENODEV; for (i = 0; i < num_queues; ++i) { @@ -366,11 +371,17 @@ static void xennet_tx_buf_gc(struct netfront_queue *queue) unsigned short id; struct sk_buff *skb; bool more_to_do; + const struct device *dev = &queue->info->netdev->dev; BUG_ON(!netif_carrier_ok(queue->info->netdev)); do { prod = queue->tx.sring->rsp_prod; + if (RING_RESPONSE_PROD_OVERFLOW(&queue->tx, prod)) { + dev_alert(dev, "Illegal number of responses %u\n", + prod - queue->tx.rsp_cons); + goto err; + } rmb(); /* Ensure we see responses up to 'rp'. */ for (cons = queue->tx.rsp_cons; cons != prod; cons++) { @@ -380,14 +391,27 @@ static void xennet_tx_buf_gc(struct netfront_queue *queue) if (txrsp.status == XEN_NETIF_RSP_NULL) continue; - id = txrsp.id; + id = txrsp.id; + if (id >= RING_SIZE(&queue->tx)) { + dev_alert(dev, + "Response has incorrect id (%u)\n", + id); + goto err; + } + if (queue->tx_link[id] != TX_PENDING) { + dev_alert(dev, + "Response for inactive request\n"); + goto err; + } + + queue->tx_link[id] = TX_LINK_NONE; skb = queue->tx_skbs[id]; queue->tx_skbs[id] = NULL; if (unlikely(gnttab_query_foreign_access( queue->grant_tx_ref[id]) != 0)) { - pr_alert("%s: warning -- grant still in use by backend domain\n", - __func__); - BUG(); + dev_alert(dev, + "Grant still in use by backend domain\n"); + goto err; } gnttab_end_foreign_access_ref( queue->grant_tx_ref[id], GNTMAP_readonly); @@ -405,6 +429,12 @@ static void xennet_tx_buf_gc(struct netfront_queue *queue) } while (more_to_do); xennet_maybe_wake_tx(queue); + + return; + + err: + queue->info->broken = true; + dev_alert(dev, "Disabled for further use\n"); } struct xennet_gnttab_make_txreq { @@ -448,6 +478,12 @@ static void xennet_tx_setup_grant(unsigned long gfn, unsigned int offset, *tx = info->tx_local; + /* + * Put the request in the pending queue, it will be set to be pending + * when the producer index is about to be raised. + */ + add_id_to_list(&queue->tx_pend_queue, queue->tx_link, id); + info->tx = tx; info->size += info->tx_local.size; } @@ -540,6 +576,15 @@ static u16 xennet_select_queue(struct net_device *dev, struct sk_buff *skb, return queue_idx; } +static void xennet_mark_tx_pending(struct netfront_queue *queue) +{ + unsigned int i; + + while ((i = get_id_from_list(&queue->tx_pend_queue, queue->tx_link)) != + TX_LINK_NONE) + queue->tx_link[i] = TX_PENDING; +} + #define MAX_XEN_SKB_FRAGS (65536 / XEN_PAGE_SIZE + 1) static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev) @@ -563,6 +608,8 @@ static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev) /* Drop the packet if no queues are set up */ if (num_queues < 1) goto drop; + if (unlikely(np->broken)) + goto drop; /* Determine which queue to transmit this SKB on */ queue_index = skb_get_queue_mapping(skb); queue = &np->queues[queue_index]; @@ -666,6 +713,8 @@ static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev) /* First request has the packet length. */ first_tx->size = skb->len; + xennet_mark_tx_pending(queue); + RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&queue->tx, notify); if (notify) notify_remote_via_irq(queue->tx_irq); @@ -990,6 +1039,13 @@ static int xennet_poll(struct napi_struct *napi, int budget) skb_queue_head_init(&tmpq); rp = queue->rx.sring->rsp_prod; + if (RING_RESPONSE_PROD_OVERFLOW(&queue->rx, rp)) { + dev_alert(&dev->dev, "Illegal number of responses %u\n", + rp - queue->rx.rsp_cons); + queue->info->broken = true; + spin_unlock(&queue->rx_lock); + return 0; + } rmb(); /* Ensure we see queued responses up to 'rp'. */ i = queue->rx.rsp_cons; @@ -1230,6 +1286,9 @@ static irqreturn_t xennet_tx_interrupt(int irq, void *dev_id) struct netfront_queue *queue = dev_id; unsigned long flags; + if (queue->info->broken) + return IRQ_HANDLED; + spin_lock_irqsave(&queue->tx_lock, flags); xennet_tx_buf_gc(queue); spin_unlock_irqrestore(&queue->tx_lock, flags); @@ -1242,6 +1301,9 @@ static irqreturn_t xennet_rx_interrupt(int irq, void *dev_id) struct netfront_queue *queue = dev_id; struct net_device *dev = queue->info->netdev; + if (queue->info->broken) + return IRQ_HANDLED; + if (likely(netif_carrier_ok(dev) && RING_HAS_UNCONSUMED_RESPONSES(&queue->rx))) napi_schedule(&queue->napi); @@ -1263,6 +1325,10 @@ static void xennet_poll_controller(struct net_device *dev) struct netfront_info *info = netdev_priv(dev); unsigned int num_queues = dev->real_num_tx_queues; unsigned int i; + + if (info->broken) + return; + for (i = 0; i < num_queues; ++i) xennet_interrupt(0, &info->queues[i]); } @@ -1633,6 +1699,7 @@ static int xennet_init_queue(struct netfront_queue *queue) /* Initialise tx_skb_freelist as a free chain containing every entry. */ queue->tx_skb_freelist = 0; + queue->tx_pend_queue = TX_LINK_NONE; for (i = 0; i < NET_TX_RING_SIZE; i++) { queue->tx_link[i] = i + 1; queue->grant_tx_ref[i] = GRANT_INVALID_REF; @@ -1848,6 +1915,9 @@ static int talk_to_netback(struct xenbus_device *dev, if (info->queues) xennet_destroy_queues(info); + /* For the case of a reconnect reset the "broken" indicator. */ + info->broken = false; + err = xennet_create_queues(info, &num_queues); if (err < 0) { xenbus_dev_fatal(dev, err, "creating queues");