aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorShlomo Pongratz <shlomop@mellanox.com>2013-02-04 15:29:10 +0000
committerRoland Dreier <roland@purestorage.com>2013-02-05 09:35:06 -0800
commit7e5a90c25f89128c096dbdb0e5451962438b1e05 (patch)
tree0f7547c36c7d7ab5ed33a2922c18e452b1b627c7
parent949db153b6466c6f7cad5a427ecea94985927311 (diff)
IPoIB: Fix crash due to skb double destruct
After commit b13912bbb4a2 ("IPoIB: Call skb_dst_drop() once skb is enqueued for sending"), using connected mode and running multithreaded iperf for long time, ie iperf -c <IP> -P 16 -t 3600 results in a crash. After the above-mentioned patch, the driver is calling skb_orphan() and skb_dst_drop() after calling post_send() in ipoib_cm.c::ipoib_cm_send() (also in ipoib_ib.c::ipoib_send()) The problem with this is, as is written in a comment in both routines, "it's entirely possible that the completion handler will run before we execute anything after the post_send()." This leads to running the skb cleanup routines simultaneously in two different contexts. The solution is to always perform the skb_orphan() and skb_dst_drop() before queueing the send work request. If an error occurs, then it will be no different than the regular case where dev_free_skb_any() in the completion path, which is assumed to be after these two routines. Signed-off-by: Shlomo Pongratz <shlomop@mellanox.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
-rw-r--r--drivers/infiniband/ulp/ipoib/ipoib_cm.c6
-rw-r--r--drivers/infiniband/ulp/ipoib/ipoib_ib.c6
2 files changed, 6 insertions, 6 deletions
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_cm.c b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
index 03103d2bd64..67b0c1d2367 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_cm.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
@@ -741,6 +741,9 @@ void ipoib_cm_send(struct net_device *dev, struct sk_buff *skb, struct ipoib_cm_
tx_req->mapping = addr;
+ skb_orphan(skb);
+ skb_dst_drop(skb);
+
rc = post_send(priv, tx, tx->tx_head & (ipoib_sendq_size - 1),
addr, skb->len);
if (unlikely(rc)) {
@@ -752,9 +755,6 @@ void ipoib_cm_send(struct net_device *dev, struct sk_buff *skb, struct ipoib_cm_
dev->trans_start = jiffies;
++tx->tx_head;
- skb_orphan(skb);
- skb_dst_drop(skb);
-
if (++priv->tx_outstanding == ipoib_sendq_size) {
ipoib_dbg(priv, "TX ring 0x%x full, stopping kernel net queue\n",
tx->qp->qp_num);
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
index a1bca70e20a..2cfa76f5d99 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
@@ -600,6 +600,9 @@ void ipoib_send(struct net_device *dev, struct sk_buff *skb,
netif_stop_queue(dev);
}
+ skb_orphan(skb);
+ skb_dst_drop(skb);
+
rc = post_send(priv, priv->tx_head & (ipoib_sendq_size - 1),
address->ah, qpn, tx_req, phead, hlen);
if (unlikely(rc)) {
@@ -615,9 +618,6 @@ void ipoib_send(struct net_device *dev, struct sk_buff *skb,
address->last_send = priv->tx_head;
++priv->tx_head;
-
- skb_orphan(skb);
- skb_dst_drop(skb);
}
if (unlikely(priv->tx_outstanding > MAX_SEND_CQE))