From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gregory Etelson <gregory@weka.io>
Subject: IXBGE VF: link state detection
Date: Wed, 24 May 2017 12:50:19 +0300
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Cc: users@dpdk.org, Ferruh Yigit <ferruh.yigit@intel.com>, wenzhuo.lu@intel.com
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Hello,

In my tests DPDK-17.05.0 process queries link state with rte_eth_link_get() each 50 msec
during 5-20 MB/sec IOs flow.
I turn Ethernet switch port down and up and check IXGBE VF PMD reaction to link state changes. 
VF PMD correctly recognize link down events but may miss link up.
When the fault occurs, subsequent calls to rte_eth_link_get will return link_status == 0 forever.
I need to reset DPDK process to get correct link state value.
My debugging shows that in case of the fault, mbx->ops.read(hw, &in_msg, 1, 0) in ixgbe_check_mac_link_vf
keeps returning non-zero value

Regards,
Gregory