I used to work for a laptop repair company. Nothing made me hate HP than having to work on their machines. Dell? Lenovo? Hell, Asus? I’d take ‘em all over an HP any day.

I have a HP laptop. I hate its UEFI.

1. Drive lock:
   This utilizes the ATA security commands. DriveLock uses master and user password. I don't know how exactly they are used, but simply the user password is used for unlocking the drive while master password is required to reset it.
   While enabling DriveLock, HP UEFI ask me for a password. Which one is it? Does it re-use it for both? Does it use the admin password as master? Does it generate and save the master password in UEFI? I should probably test it out with hdparm.

2. Vanishing boot entries:
   Did you just boot up from external drive? Where's the boot entries? ¯⁠\⁠_⁠(⁠ツ⁠)⁠_⁠/⁠¯ Can you at least add them in UEFI settings like with any normal computer? Nope. You need to use either efibootmgr or bootice. I usually just boot Hiren's Boot (PE) and use Bootice. Is that it though? Nope. The boot priority won't be saved. You need to head back into UEFI settings (and don't you dare forget to unlock your drive, or else start all over), go into boot settings, "OS Boot Manager" and then put them in correct order. What they don't tell you is that if you get out to "Save and exit", this won't be saved. You have to press one of the F keys, I believe F10, to save the boot order, and just then you can "Save and exit".