Well, after wasting a bunch of time trying every combination of login names imaginable with the password I know works I guess it's time to just completely re-do my Mac from the ground up, because Why Not.
In very rare circumstances, such as when a power failure interrupts macOS installation, your Mac might start up to a circled exclamation point. This means that the firmware stored in your computer's memory needs to be revived or restored.
@thephd@Sobex It can't make anything worse so you might as well try it! Fedora should have usable packages (you might need to select an older macOS version to restore since I think the latest builds triggered some issues that just got fixed but not released yet).
Can you still get into recoveryOS though? If you can then it should be fixable without DFU... (DM me if you want me to help troubleshoot ^^)
@Sobex@lina Alas, I am screwed in this regard (it won't boot into RecoveryOS anymore, I think it broke) and I always get put on the exclamation point. I don't have Linux machine but I can pribably make a liveusb with idevicerestore on it or something....?
@thephd@lina This will not work because Apple Silicon does not boot off USB. You always boot the kernel from a container on the internal drive. The kernel can then do other things like load the remainder of the system from a USB drive, but if you've hosed the Boot process, you won't boot from USB either.
If you don't have any other computer lying around, idevicerestore can't do anything for you.
@thephd@lina At least your mac has a screen to display the exclamation mark. Mac Minis and Mac Studios do not have this luxury and may resort to flashing a Morse SOS as the only way to tell that the boot loader is hosed and they need to be revived by another device.
@Sobex@thephd They actually used to support displaying that over HDMI... but Apple removed it in an update early on for some reason. Maybe they didn't like that it only worked over HDMI and not over Thunderbolt/Type C?
@thephd does it not even boot into internet recovery? That's capable of fixing almost everything in my experience, if you haven't tried that specifically.
If you can't even get into that... yep. Box. It's super annoying that they can't just use a USB drive to bootstrap it. It has bitten me once before.