[PATCH 3.16 038/212] IB/ipoib: Change list_del to list_del_init in the tx object

[Ben Hutchings]

3.16.44-rc1 review patch.  If anyone has any objections, please let me know.

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From: Feras Daoud <ferasda@xxxxxxxxxxxx>

commit 27d41d29c7f093f6f77843624fbb080c1b4a8b9c upstream.

Since ipoib_cm_tx_start function and ipoib_cm_tx_reap function
belong to different work queues, they can run in parallel.
In this case if ipoib_cm_tx_reap calls list_del and release the
lock, ipoib_cm_tx_start may acquire it and call list_del_init
on the already deleted object.
Changing list_del to list_del_init in ipoib_cm_tx_reap fixes the problem.

Fixes: 839fcaba355a ("IPoIB: Connected mode experimental support")
Signed-off-by: Feras Daoud <ferasda@xxxxxxxxxxxx>
Signed-off-by: Erez Shitrit <erezsh@xxxxxxxxxxxx>
Reviewed-by: Alex Vesker <valex@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx>
Reviewed-by: Yuval Shaia <yuval.shaia@xxxxxxxxxx>
Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/infiniband/ulp/ipoib/ipoib_cm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/infiniband/ulp/ipoib/ipoib_cm.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
@@ -1376,7 +1376,7 @@ static void ipoib_cm_tx_reap(struct work
 
 	while (!list_empty(&priv->cm.reap_list)) {
 		p = list_entry(priv->cm.reap_list.next, typeof(*p), list);
-		list_del(&p->list);
+		list_del_init(&p->list);
 		spin_unlock_irqrestore(&priv->lock, flags);
 		netif_tx_unlock_bh(dev);
 		ipoib_cm_tx_destroy(p);