From 479a079663bd4c5f3d2714643b1b8c406aaba3e0 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Tue, 7 Feb 2006 16:37:08 -0800 Subject: [PATCH] IPoIB: Don't start send-only joins while multicast thread is stopped Fix the following race scenario: - Device is up. - Port event or set mcast list triggers ipoib_mcast_stop_thread, this cancels the query and waits on mcast "done" completion. - Completion is called and "done" is set. - Meanwhile, ipoib_mcast_send arrives and starts a new query, re-initializing "done". Fix this by adding a "multicast started" bit and checking it before starting a send-only join. Signed-off-by: Michael S. Tsirkin Signed-off-by: Roland Dreier --- drivers/infiniband/ulp/ipoib/ipoib.h | 1 + drivers/infiniband/ulp/ipoib/ipoib_multicast.c | 15 +++++++++++++++ 2 files changed, 16 insertions(+) diff --git a/drivers/infiniband/ulp/ipoib/ipoib.h b/drivers/infiniband/ulp/ipoib/ipoib.h index e0a5412b7e68..2f85a9a831b1 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib.h +++ b/drivers/infiniband/ulp/ipoib/ipoib.h @@ -78,6 +78,7 @@ enum { IPOIB_FLAG_SUBINTERFACE = 4, IPOIB_MCAST_RUN = 5, IPOIB_STOP_REAPER = 6, + IPOIB_MCAST_STARTED = 7, IPOIB_MAX_BACKOFF_SECONDS = 16, diff --git a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c index ccaa0c387076..1c7148208ce8 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c @@ -601,6 +601,10 @@ int ipoib_mcast_start_thread(struct net_device *dev) queue_work(ipoib_workqueue, &priv->mcast_task); mutex_unlock(&mcast_mutex); + spin_lock_irq(&priv->lock); + set_bit(IPOIB_MCAST_STARTED, &priv->flags); + spin_unlock_irq(&priv->lock); + return 0; } @@ -611,6 +615,10 @@ int ipoib_mcast_stop_thread(struct net_device *dev, int flush) ipoib_dbg_mcast(priv, "stopping multicast thread\n"); + spin_lock_irq(&priv->lock); + clear_bit(IPOIB_MCAST_STARTED, &priv->flags); + spin_unlock_irq(&priv->lock); + mutex_lock(&mcast_mutex); clear_bit(IPOIB_MCAST_RUN, &priv->flags); cancel_delayed_work(&priv->mcast_task); @@ -693,6 +701,12 @@ void ipoib_mcast_send(struct net_device *dev, union ib_gid *mgid, */ spin_lock(&priv->lock); + if (!test_bit(IPOIB_MCAST_STARTED, &priv->flags)) { + ++priv->stats.tx_dropped; + dev_kfree_skb_any(skb); + goto unlock; + } + mcast = __ipoib_mcast_find(dev, mgid); if (!mcast) { /* Let's create a new send only group now */ @@ -754,6 +768,7 @@ out: ipoib_send(dev, skb, mcast->ah, IB_MULTICAST_QPN); } +unlock: spin_unlock(&priv->lock); }