Last modified by Leon Poon on 2020/09/20 14:28
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1 In a LG V20, Full-Disk Encryption (FDE) makes use of Secure Execution Environment (SEE, by Qualcomm). The password/pin you provide to Android will be used to unlock encryption key stored in SEE.
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3 When Lineage OS (as of 17.1) encrypts an unencrypted disk, it tries to set up SEE with your password/pin. If SEE was already previously set up with an old password/pin at that time, it will reject the attempt by Lineage OS to set up a new one. This drops your phone into a boot-loop because Lineage OS is not able to make use of SEE for FDE.
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5 If you erase the current key from SEE then SEE will accept a new setup from Lineage OS.
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7 How to erase FDE encryption key from SEE:
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9 1. Root - use magisk
10 1. Download the attached [[(% class="wikiattachmentlink wikiattachmentlink" %)##mymod##>>attach:mymod]](%%) binary executable into your phone.
11 1. Do adb shell
12 1. Become root: ##su##
13 1. move the ##mymod## file into ##/sbin##
14 1. ##chmod +x /sbin/mymod##
15 1. Run: ##/sbin/mymod##
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17 You can check whether it has successful removed the old key material by looking at logcat for lines starting with "mymod". Indication of a 0 status means successful.
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19 After running mymod and successfully removing the pre-existing encryption key from SEE, you can immediately ask Lineage OS to do FDE.