[dpdk-dev] [PATCH 2/2] net/e1000: fix mailbox interrupt handler

[Qi Zhang <qi.z.zhang@intel.com>]

Mailbox interrupt handler only take care of the PF reset notification,
for other message mbx->ops.read should not be called since it get chance
to break the foreground VF to PF communication.

Fixes: 316f4f1adc2e ("net/igb: support VF mailbox interrupt for link up/down")
Cc: stable@dpdk.org

Signed-off-by: Qi Zhang <qi.z.zhang@intel.com>
---
 drivers/net/e1000/igb_ethdev.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/net/e1000/igb_ethdev.c b/drivers/net/e1000/igb_ethdev.c
index fdc139f..0d8bc49 100644
--- a/drivers/net/e1000/igb_ethdev.c
+++ b/drivers/net/e1000/igb_ethdev.c
@@ -2970,13 +2970,17 @@ void igbvf_mbx_process(struct rte_eth_dev *dev)
 	struct e1000_mbx_info *mbx = &hw->mbx;
 	u32 in_msg = 0;
 
-	if (mbx->ops.read(hw, &in_msg, 1, 0))
-		return;
+	/* peek the message first */
+	in_msg = E1000_READ_REG(hw, E1000_VMBMEM(0));
 
 	/* PF reset VF event */
-	if (in_msg == E1000_PF_CONTROL_MSG)
+	if (in_msg == E1000_PF_CONTROL_MSG) {
+		/* dummy mbx read to ack pf */
+		if (mbx->ops.read(hw, &in_msg, 1, 0))
+			return;
 		_rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_RESET,
 					      NULL, NULL);
+	}
 }
 
 static int
-- 
2.7.4