[dpdk-stable] patch 'net/ixgbe: fix mailbox interrupt handler' has been queued to LTS release 16.11.5

[luca.boccassi at gmail.com]

Hi,

FYI, your patch has been queued to LTS release 16.11.5

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 01/28/18. So please
shout if anyone has objections.

Thanks.

Luca Boccassi

---
>From 4dde0d6e4099818118804d0ee203e92a4a7ac313 Mon Sep 17 00:00:00 2001
From: Qi Zhang <qi.z.zhang at intel.com>
Date: Wed, 27 Dec 2017 15:22:29 -0500
Subject: [PATCH] net/ixgbe: fix mailbox interrupt handler

[ upstream commit 6810c6392656f05b3f9d45806a87ee683337a15b ]

Mailbox interrupt handler only takes care of PF reset notification, for
other message ixgbe_read_mbx should not be called since it gets chance
to break the foreground VF to PF communication.
This can be simply repeated by 'testpmd>rx_vlan rm all 0'.

Fixes: 77234603fba0 ("net/ixgbe: support VF mailbox interrupt for link up/down")

Signed-off-by: Qi Zhang <qi.z.zhang at intel.com>
Acked-by: Wei Dai <wei.dai at intel.com>
---
 drivers/net/ixgbe/ixgbe_ethdev.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c b/drivers/net/ixgbe/ixgbe_ethdev.c
index d9cc02f47..f870069a7 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.c
+++ b/drivers/net/ixgbe/ixgbe_ethdev.c
@@ -7571,12 +7571,17 @@ static void ixgbevf_mbx_process(struct rte_eth_dev *dev)
 	struct ixgbe_hw *hw = IXGBE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
 	u32 in_msg = 0;
 
-	if (ixgbe_read_mbx(hw, &in_msg, 1, 0))
-		return;
+	/* peek the message first */
+	in_msg = IXGBE_READ_REG(hw, IXGBE_VFMBMEM);
 
 	/* PF reset VF event */
-	if (in_msg == IXGBE_PF_CONTROL_MSG)
-		_rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_RESET, NULL);
+	if (in_msg == IXGBE_PF_CONTROL_MSG) {
+		/* dummy mbx read to ack pf */
+		if (ixgbe_read_mbx(hw, &in_msg, 1, 0))
+			return;
+		_rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_RESET,
+					      NULL);
+	}
 }
 
 static int
-- 
2.14.2