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rb3

macrumors newbie
Original poster
Jun 9, 2015
1
0
Hi, I've been looking around for weeks for a way to read out the GPU ROM into a file. I have a Mid-2014 rMBP with the Nvidia GT 750m graphics card. I'm trying to get VGA passthrough to work on KVM+Qemu Arch Linux (see this forum thread: https://bbs.archlinux.org/viewtopic.php?pid=1528524#p1528524). Qemu is not able to read the contents of the GPU ROM, so I need to pass it a valid ROM file.

I have tried fiddling with the corresponding PCI files in the "/dev" directory on Linux, but issuing `cat rom` results in a "input/output error". I have looked around in "/sys/firmware/efi/efivars", but I haven't been able to figure out if the two ROM files in there are for the GPU (`cat` doesn't output valid ROM contents). I have also tried booting into a Windows To Go external hard-drive, and using GPU-Z to try and extract the ROM, but GPU-Z complains about not being able to read the ROM.

Is there some trick or hack that I can do to get the ROM file? Or does anyone actually have a ROM file for this machine?

Thanks in advance for the help!
 
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