When bl is not unlocked, you cannot root or flash masks and third-party recs. BL is the abbreviation of bootloader, which is the boot program. Bootloader lock mainly checks the system signature, kernel signature and recovery signature during the boot process. If the signatures are inconsistent, the boot will be terminated. BL is a lock that restricts users from flashing third-party ROMs and third-party recovery and restricts rooting. Locking recovery and fastboot will not be flashed or modified by other things. When bl is not unlocked, it is impossible to root, and it is impossible to flash masks and third parties. rec.

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