OK, so here's what I came up with for now:
a "rescue pack" which enables an SSH server in diags, plus a simple startup script that checks for the existence of a /mnt/us/ENABLE_DIAGS file, and reboots into diags if it is present.
It works on my device (and should work on others), but please report back in case it doesn't.
Yes, I'm fully aware that this can't solve all of the "brick situations" (it requires the main and user partitions to at least be in a "somewhat" bootable state), and that USB downloader mode/fastboot etc. would be much preferrable, but... well, until somebody figures out how to get there, I guess that this is better than nothing.
Rebuilt to support all currently known Kindle Voyage, PW2, PW1, and Touch models.
Updated to support all currently known Kindle PW2, PW1, and Touch models.
Fixed a serious issue where SSH access would only work once on certain models. If you currently have installed a previous version, I STRONGLY recommend to download and install the current one.
NOTE: If you're looking for something working on newer devices, try the one in NiLuJe's snapshots
thread. -- NiLuJe