Out of nowhere, the boot login/decryption screen started to become unresponsive. Fortunately, the screen is responsive for about a second every minute (or so). This way I can still type in my password at 2 chars / min (*o*) and log in.
Once logged in, everything is fine. Non-boot logging screens are not affected. The same is the case when booting from an older Mac OS via USB. The closest related problem I could find was macOS Sierra boot problem related to Apple SD Card reader driver.
But the described behavior is not a perfect match. However, the last thing I did before the issue appeared was to copy a file onto a SD card I had never connected previously (I always have a built-to-fit SD card connected).
- Mac OS 11.6.7 (internal, last updated after appearance of bug) & Mac OS 10.15 (external, USB)
- SSD exchanged for NVMe (not fully supported by hardware)
- FileVault active
Full list of symptoms:
- Time between boot sound and apple logo increased from seconds to minutes
- Duration apple logo is shown also increased from seconds to minutes
- Boot login screen unresponsive/frozen for about a min at a time
- Boot login screen responsive for about a second after every unresponsive min
- Text field caret frozen
- Trackpad inputs during unresponsive time lead to expected update of the position of the cursor during the responsive second
- Keyboard inputs only registered during responsive second (major issue as typing a long password then takes forever)
- Reset SMC
- Reset PRAM
- Disabling FileVault
- Disabling Bluetooth
- Fix disk in recovery mode (no errors found)
- Connecting USB keyboard does not help (no power at that stage)
I am looking into possible offending kexts and SD card reader drivers at the moment but as rebooting takes at least 15 min, progress is slow and frustrating...
UPDATE: Rebooting without SD card gives a responsive login screen! So the SD cardreader is indeed the culprit. Now I only need a way to fix it on the sw side...