alt Hacker NewsFun fact, the Nintendo Switch blows fuses [0] when they do a patch that’s for security/jailbreaking. If I recall there’s something like 12 or 16 fuses they can employ over the life of the product to ensure you can’t rollback updates that prevent piracy. Nvidia builds these fuses into the board.
So if you’ve blown 4 fuses you can’t do a patch that requires only 2 fuses to have blown, it’s a pretty wild solution.
Edit: it’s actually 22 fuses
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Wouldn't it be great if companies spent the time and effort needed for all these wonderful things that prevent the owner from using the hardware they own how they see fit and instead invested the resources into making the product better ?
All this is basically a fragile anti-user timebomb that will only generate more avoidable e-waste eventually.
I’m not following. Why would it be helpful to check how many fuses had been blown? And how could you have more blown fuses than you’re supposed to?
It isn't that wild; the typical name for it is anti-rollback, and you probably have at least one device that implements it. Most Android devices have anti-rollback efuses to prevent installing older versions of the bootchain\bootloader; they might still allow you to downgrade the OS (depends on the vendor, if memory serves). Instead of using efuse counters, anti-rollback counters can also be implemented by Replay Protected Memory Block (RPMB), which is implemented by many flash storage (eMMC often supports RPMB, but other storage types can as well). It is possible to implement anti-rollback mechanisms on x86_64 by utilizing a TPM [0], but as far as I know, only Chrome OS does this.
[0]: https://www.chromium.org/developers/design-documents/tpm-usa...