New PCIe® good packets received will be discarded. There are no signals to indicate the Rx buffer is overflow for Hard IP and Soft IP. The error TLPs will be detected by the core and it will delete them without being presented to the application layer. Rx errors such as Receiver Overflow, Unexpected completion, etc. will be detected and handled by the core and this process is transparent to the application layer.
Please refer to solution rd11232010_135 for the steps to prevent Rx buffer overflow.