fcoe: don't deliver FCP frames to target modules in softirq context

Under certain conditions when FCP frames arrive on the correct CPU
we deliver them in the softirq context.  This is unexpected for
target modules like tcm_fc and fcst, and causes them to get errors.

Add a check for the FC frame header F_CTL bit EX_CTX, and don't
deliver in softirq context if that bit is off.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>

---
 drivers/scsi/fcoe/fcoe.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)


---
diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
index 844d618..e4c3128 100644
--- a/drivers/scsi/fcoe/fcoe.c
+++ b/drivers/scsi/fcoe/fcoe.c
@@ -1340,8 +1340,11 @@ int fcoe_rcv(struct sk_buff *skb, struct net_device *netdev,
 	 * This lets us process completions without context switching from the
 	 * NET_RX softirq, to our receive processing thread, and then back to
 	 * BLOCK softirq context.
+	 * Don't do this if EX_CTX is off as it causes problems for target
+	 * modules that don't expect to be called in softirq context.
 	 */
 	if (fh->fh_type == FC_TYPE_FCP &&
+	    (ntoh24(fh->fh_f_ctl) & FC_FC_EX_CTX) &&
 	    cpu == smp_processor_id() &&
 	    skb_queue_empty(&fps->fcoe_rx_list)) {
 		spin_unlock_bh(&fps->fcoe_rx_list.lock);
