Oneplus phone update introduces hardware anti-rollback: Difference between revisions

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==Technical mechanism==
==Technical mechanism==


The anti-rollback mechanism uses Qfprom (Qualcomm Fuse Programmable Read-Only Memory), a region on Qualcomm processors containing one-time programmable electronic fuses. These microscopic components are physically altered when "blown"; a controlled voltage pulse permanently changes the fuse's state from "0" to "1." This change cannot be reversed by any software means.<ref name="xda-warning" />
The anti-rollback mechanism uses Qfprom (Qualcomm Fuse Programmable Read-Only Memory), a region on Qualcomm processors containing one-time programmable electronic fuses. These microscopic components are physically altered when "blown"; a controlled voltage pulse permanently changes the fuse's state from "0" to "1." This change cannot be reversed by any software means.<ref name="xda-warning" /> A complete motherboard replacement is the only possible method to remedy it.


DroidWin explained that the implementation works similarly to how Knox gets tripped on Samsung devices upon unlocking the bootloader: both are e-fuses embedded in the motherboard that become permanently fused upon triggering. Changing the motherboard is the only way to restore the default state.<ref name="droidwin" />
DroidWin explained that the implementation works similarly to how Knox gets tripped on Samsung devices upon unlocking the bootloader: both are e-fuses embedded in the motherboard that become permanently fused upon triggering. Changing the motherboard is the only way to restore the default state.<ref name="droidwin" />