I have a PCI-E Dell Perc 6/i RAID card that I'd like to flash with the latest firmware. Apparently I need either a Redhat / Centos OS or Windows in order to flash the firmware, but I have a VMWare 5.0.1 ESX hypervisor installed on the box and a CentOS guest OS. My motherboard support IOMMU and I have successfully used VMWare's PCI Passthrough feature to give VMs exclusive access to a PCI-E device. Is it safe to flash the firmware of a PCI-E device if that device is passed through to a single VM using the passthrough feature of VMware? Or should I boot one of the supported OSes directly on the bare metal?