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by timschumi 414 days ago
> Screwing up EFI vars doesn't make most systems unbootable. I have corrupted my EFI vars quite a few times trying to do funny things. UEFI implementations do tend to be buggy, but not all of them are that catastrophically bad.

For what it's worth, I have a laptop here that can be irrevocably (short of having a flash memory dump on-hand that can be flashed back) bricked just by messing around with EFI variables through fully intentional operations (i.e. operations that would be available to any program with Administrator privileges on Windows, or the root user on Linux).
1 comments
jchw 414 days ago
As far as I know virtually all of the EFI vars will be stored on battery-backed NVRAM, so the usual solution is to just clear that, by removing the CMOS battery. I am pretty sure the only solution are things you definitely can not read or write from the host OS (e.g. BIOS passwords.) Does require partially disassembling the laptop though, and I know there's at least a couple random models of laptop that actually stop working if you clear the NVRAM (lol)
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jchw 414 days ago
*only solution = only exceptions

Not sure how that happened.

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