Hello, I am not sure if this is possible but is there a way to modify the BIOS in order to completely hide a PCIe device from the operating system/not allow the CPU to access it?

@zabadih12 - Much more details needed here, what are you trying to hide and why? I need to know what you're doing so I can think about this like you are
And, explain more, you want it hid from the OS, but not the BIOS?? How do you expect it to function if "hidden"?

I am currently using the a pcie screamer along with the pcileech project for a video game cheat. In short, PCILeech uses PCIe hardware devices to read and write target system memory. This is achieved by using DMA over PCIe. No drivers are needed on the target system.

This makes it very easy to read/write memory on a target pc from an "attacker" pc without installing any software onto the target pc that the anticheat would detect.

The anticheat have gotten very good recently and are able to detect the existence of the pciescreamer conducting these dma operations. https://blog.esea.net/esea-hardware-cheats/

This is why I would like to be able to hide the existence of this pcie device and I was told that this could be done by modifying the bios.


Currently, when setting the device and vendor id of this pcie screamer as 0xffff, the pcie card shows empty in the bios and doesn't show up in pcieslot analysis software such as SIV64, but I am still able to do dma operations just fine. However, the anticheat can still detect the presence of the pciescreamer in this scenario. This is why I would like to have a way to completely block the OS from seeing this device.

@zabadih12 - Thanks for the info, now I understand a little bit more. I think maybe disable load of option rom for PCI/PCIE devices could work, but then possibly no display, so not ideal.
Can you link me to any discussions of BIOS modification for this purpose? Disable slot directly via BIOS not ideal, then no power/function, so I really need to see someone talk about this BIOS mod and what they do, or set etc, so then I can do

Will the device still work if you run a VMWare system and dedicate the card to that system instead of your main system? Does this still allow the card to function for your usage, or it's completely unavailable to your system and only available to the VMWare system?

https://www.unknowncheats.me/forum/anti-...-cheats-10.html

Page 10 and 11 of the above topic and page 1 and 2 of the below is almost all I have unfortunately.

https://www.unknowncheats.me/forum/anti-...tml#post2685989


I haven't quite tested it's functionality with virtual machines, but I know that with intel vt-d enabled, I am unable to read memory of the target system.

Can you ask in one of those threads for someone to generally discuss/layout a BIOS mod, what is done, ask for answer to be in a detailed way saying that "someone else will read the info and mod the BIOS for you"
All this ID nulling makes me wonder, can't you set ID as some other card and then scans for such things will ignore it? Like set the ID as a LAN card or Ethernet Modem or something like that, instead of 0xFFFF?
Nothing in page 10-11 of first link for BIOS edit, post #7 of second link says exactly what I thought (if disable in BIOS = Disabled, you cannot use), nothing else there discusses or helps with BIOS editing either.

Sorry, without info on this actual edit you need, nothing I know to do really other than disable the port, but then that = disabled so will not start and is not what you want I think.

Im afraid no one will share such info with me. I have tried asking multiple people and they all declined to help.

Also, trying to spoof the card and changing it's IDs/pcie configuration space to that of a different card still leaves traces of the original card. In the "detecting hardware cheats" article they mention this.

Try asking again, maybe tell them one of the BIOS editing pro's over at this forum will help you in private, if they can give any edit details on what needs done/set/changed etc.
Maybe then they will know you are serious person who wants to use, and not some game company employee trying to figure out hacks people are using or trying to find cheaters etc.