Please find the known bug of cisco fnic driver (storage) here and due to this esxi will get psod. Hence requesting to update this driver version . If your environment is quite stable please ignore it , No need to update the driver , in certain scenarios only you will get PSOD.
Latest Driver Version
Adapter Driver = 188.8.131.52a (FNIC) / 184.108.40.206 (ENIC)
Adapter Firmware = 4.0(1)
Before updating compulsory ensure that your device is compatible with this driver in cisco ucs manager interoperability tool.
also be in the safer side , check with TAC as well. This mostly applicable to CISCO UCS B200 M3 Blades with 6248 FI , 2204 /2208 IOM and MLOM VIC 1240