On May 15, Lenovo released a new BIOS firmware for ThinkPad X1 Carbon Gen 6. The latest of the version of the firmware is 1.48. (There previous version 1.47 was withdrawn for some unknown reason.)

Here is the changes in this releases:

CHANGES IN THIS RELEASE
  Version 1.48

[Important updates]
- Update includes a security fix.

[New functions or enhancements]
- Updated the Diagnostics module to version 04.12.001.

[Problem fixes]
- Fixed an issue where Force PXE boot by Intel AMT does not work.

As of today, this new firmware is not yet available via LVFS on Fedora 32. So for those who are impatient like me, we can install this firmware ourselves. Warning: In no way will I be liable if your brick your own machine when you follow this guide!

First download the firmware from Lenovo website:

❯❯ curl -O https://download.lenovo.com/pccbbs/mobiles/n23ul25w.zip
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 10.9M  100 10.9M    0     0   839k      0  0:00:13  0:00:13 --:--:-- 1028k
❯❯❯ unzip n23ul25w.zip
Archive:  n23ul25w.zip
  inflating: N23ET73P.cab            
  inflating: N23ET73W.cab            
 extracting: N23HT35W.cab  
  • N23ET73P.cab - “Non-Absolute Persistence Module” UEFI BIOS 1.48
  • N23ET73W.cab - (Absolute Persistence Module) UEFI BIOS 1.48
  • N23HT35W.cab - Embedded Controller Program (ECP) 1.20

In my case, my machine already has ECP 1.20 installed, so I’ll skip re-install it. For the UEFI BIOS firmware, it’s important to pick the right one. The safest thing to do is to follow the instruction provided officially by Lenovo: ReadMe for 1.48 BIOS:

DETERMINING WHICH VERSION IS INSTALLED

 [Checking on ThinkPad Setup]

  1. Turn on the computer.
  2. While the "To interrupt normal startup, press Enter" message is displayed
     at the lower-left area or lower-center of the screen, press the F1 key.
     The ThinkPad Setup menu will be displayed. If a password prompt appears,
     type the correct password.
  3. Locate the UEFI BIOS Version line and Embedded Controller Version line.
     "UEFI BIOS version (BIOS ID)" will be shown on the UEFI BIOS Version line.
  4. Turn off the computer.

I’m very sure that I have “Absolute Persistence Module” version installed. Therefore, I will update the firmware with N23ET73W.cab. Second warning, make sure you’re absolutely sure which version of BIOS you’re running before proceeding with the firmware update.

❯❯ sudo fwupdmgr install N23ET73W.cab
[sudo] password for kenno: 
Decompressing…           [***************************************]
Authenticating…          [***************************************]
Installing on System Firmware…                                   ]
Scheduling…              [***************************************]
Successfully installed firmware

An update requires a reboot to complete. Restart now? [y|N]: y

I’m going to restart the machine now. If there is no problem, that’s it and there will be no follow up process. Good luck with your firmware update!

References: