After a world update, one of my Obarun machines became unresponsive. The obligatory reboot revealed that it boots until it tries to load amdgpu/picasso_ip_discovery.bin, which it can't find - because it doesn't exist. Not on the machine, not on any machine, not in the file lists for amdgpu. Then it spazzes out and drops me into a rescue TTY with a read-only file system.
dmesg doesn't show anything else going wrong, just an error in finding the file, and then the whole boot sequence stopping dead. fsck doesn't find anything wrong with the file system, but I still can't get it to allow file writing, so I can't roll back to an earlier kernel [if that is even the problem, I'm entirely open to the possibility that this is not the issue].
Every attempt I've made to use the 66 tools to see what is going on, is blocked by 66 not being able to open scandirs. Pacman won't work, so I can't roll back the update either. Using mount -a or mount -o rw / don't work, it tells me the source is ro, and refuses to give me access.
How can I get the machine running again?
