rapidio/rionet: fix deadlock on SMP

commit 36915976eca58f2eefa040ba8f9939672564df61 upstream.

Fix deadlocking during concurrent receive and transmit operations on SMP
platforms caused by the use of incorrect lock: on transmit 'tx_lock'
spinlock should be used instead of 'lock' which is used for receive
operation.

This fix is applicable to kernel versions starting from v2.15.

Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/net/rionet.c b/drivers/net/rionet.c
index c0f097b..66cd4ce 100644 (file)
--- a/drivers/net/rionet.c
+++ b/drivers/net/rionet.c
@@ -269,7 +269,7 @@ static void rionet_outb_msg_event(struct rio_mport *mport, void *dev_id, int mbo
        struct net_device *ndev = dev_id;
        struct rionet_private *rnet = netdev_priv(ndev);
 
-       spin_lock(&rnet->lock);
+       spin_lock(&rnet->tx_lock);
 
        if (netif_msg_intr(rnet))
                printk(KERN_INFO
@@ -288,7 +288,7 @@ static void rionet_outb_msg_event(struct rio_mport *mport, void *dev_id, int mbo
        if (rnet->tx_cnt < RIONET_TX_RING_SIZE)
                netif_wake_queue(ndev);
 
-       spin_unlock(&rnet->lock);
+       spin_unlock(&rnet->tx_lock);
 }
 
 static int rionet_open(struct net_device *ndev)