Xilinx Answer 76889
When using an HDIO or MIO output powered at 3.3V or 2.5V, a race condition can exist between output data and the tristate control that can result in an incorrect output value. The following use cases involving HDIO or MIO powered at 3.3V or 2.5V might be affected: HDIO OBUFT or IOBUFT, MIO system monitor I2C/PMBus interface, MIO SelectMAP interface, MIO USB 2.0 interface, JTAG TDO, JTAG HDIO and MIO EXTEST (board interconnect test), global tristate (GTS) assertion, or system reset (SRST) assertion.
There is no reliability concern if the device is not stuck in an incorrect output state for more than 1% of its lifetime.
This issue will not be fixed for the devices listed in the Errata Summary table.