net/ixgbe: fix mailbox interrupt handler

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")
Cc: stable@dpdk.org
Signed-off-by: Qi Zhang <qi.z.zhang@intel.com>
Acked-by: Wei Dai <wei.dai@intel.com>

diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c b/drivers/net/ixgbe/ixgbe_ethdev.c
index 6284ad8..4f4334d 100644 (file)
--- a/drivers/net/ixgbe/ixgbe_ethdev.c
+++ b/drivers/net/ixgbe/ixgbe_ethdev.c
@@ -8141,13 +8141,17 @@ 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)
+       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