Comment 197 for bug 1734147

@Kyle Alexander Buan
It sounds like you are probably fine. If you are able to make(and save) changes to UEFI then I don't think you are in the same boat as those of us who have been bit by this bug. You may have an affected model, but as of now you don't seem to have hit the wall so to speak.

I also wanted to add a few details clarifying the status on my Toshiba Satellite S55T-B5233.
I don't have as much time to really pay attention to what's going with my computers as I might like these days. Too many distractions with all the kids at home and learning new things for work. I didn't initially make the connection that my UEFI firmware was broken by the Ubuntu 17.10 install. I was going to try Solus and could not get my thumbdrive to boot. From there things went south quickly.I tried to enter the UEFI firmware settings to check legacy mode and secure boot, but inputting F2 to enter setup just caused a reboot.

I tried using grub to manually boot the thumbdrive, but without luck despite the device showing up in ls on the grub command line. I tried installing refind, flashing a "bios" update from windows 10, reading boot entries with efibootmgr and then trying to modify them. I broke my grub entries and nothing worked. Then finally I copied the boot structure from another Ubuntu install by mounting the hdd on that computer to fix the entries GRUB2 boot cfg entries and get it booting again. Then I decided that since (in my mind) Windows 10 was somehow responsible for everything that I should just chainload my Windows 10 USB install media from GRUB (the only USB boot that I could actually get working correctly) blow away my ubuntu install, then let Windows delete all the partitions and re-install, magically fixing the UEFI settings on the way.

Despite already clearly understanding that the partition table and boot files were critical I did not back up the necessary information. What an idiot!

So here I am with a completely non-booting machine. I can't enter UEFI Firmware Settings. I can't boot from USB. I have had zero success getting the HDD to boot again. I have an arduino Uno and was thinking about buying a soic8 test clip to read and reprogram the chip. I don't often work low level, but have on many occasions. In the past I have hardmodded and recovered Original Xbox game consoles using a homemade Serial programmer. Recently I dug into my ankercam and wired in a connection to the debug console. So direct soldering isn't out of the question, but I'd like to avoid it if possible. Maybe I can use a potato chip bag clip and some spare wire to make my own clip on adapter.

My best assessment is that the UEFI is located on a chip with the following text:
AH1430
258648SIC
E57651

I can't seem to come up with anything while searching though. Any thoughts are welcome. I'm happy to be a guinea pig. Any useful links or information is greatly appreciated. Sorry if this post is incoherent or rambling, but it's late here and my brain doesn't seem to be working quite right.