KDE 5 Update Broke Laptop

[lnx64]

Let me start by saying that I have been using Linux for years, and have worked in IT all my life. But today I have seen something I never thought I would actually see. Updating to the KDE Plasma 5 desktop actually broke my laptop. Right on first reboot I was getting a perfectly good boot image. Then when SDDM loaded, it all went down hill from there.

http://i.imgur.com/UDcFtXIh.jpg

That was the last thing my laptop was ever capable of producing now. I now have no POST. Well it has post but no video now. Backlight has no power. When artificially backlighting it there is still no video. Even more strange, this laptop has two GPUs. Both are gone and no video from either. I tried reseating everything socketed, pulling battery clearing CMOS (being a Mac its the PRAM and SMC, both of which I tried clearing).

I've never seen Linux kill hardware before, and I'm not even sure how. I'm thinking it wrote to something it shouldn't have written too. But, it really worked EFI if that's the case. No video even if the hard drive is pulled (it should show a folder with a ? Mark). Nope. Gone.

Try KDE 5 Plasma they said. It'll be great they said. Nope it killed my laptops video.

FYI it does boot but just no video thanks to I'm guessing sddm since it was the login screen it immediately had issues with.

[lnx64]

External display works. Internal LCD controller is dead since the update. This is going to be a costly repair. Not too happy. It is beta though. Just sucks though.

Going to be easier to replace laptop. But I'm not too happy that KDE did this. So I think I need to part ways, despite being a KDE user since 1.

[Snowhog]

I won't say your supposition that KDE 5 was the proximate cause of your laptops demise, but I will say that it's highly unlikely. It's far more likely to have been coincidental to hardware failure. Just say'n.

[lnx64]

I'm sorry but I don't agree. I don't agree at all. Boot was good RIGHT till SDDM loaded. Then it **** itself and now is incapable of booting to the internal screen.

Of course KDE supporters will claim its coincidence, but you need to REALLY look at it objectively. What does SDDM do, how is it accessing the video card, what is it sending to the LCD controller? There is a clear cause of failure here. I'm not even bringing up a lawsuit as its beta software and I took my chances. But there needs to be something looked into to prevent this from happening again to others.

[lnx64]

I've been using Linux and doing IT, engineering for enough years to know that yes, you CAN damage a computer with a bug. I have this laptop on the bench now to scope out stuff. I will find what plasma 5 did and what part is at fault.

[kubicle]

There is very little point in venting at us (although I know some things call for some venting), I'm sure everyone here (including myself) would appreciate it very much if you manage to track down a possible hardware affecting bug, no matter where the bug is.

sddm is pure Qt, though, it doesn't use kde frameworks or plasma (these get loaded only after you log in from sddm), so plasma5 is not likely to be the problem.

I don't know much of sddm internals (I still use kdm on 15.04 with plasma5) so I obviously can't rule sddm out...but it's also possible the bug (if that's the case) can be elsewhere in the graphics stack (even if it manifested when sddm loaded)...ubuntu is fairly experimental with it's kernel and graphic driver versions and modifications, and also does some tinkering with qt and the rest of the graphics stack to support Canonical's Mir, so it's possible there are bugs in ubuntu that upstream sddm development is not aware of.

I assume you weren't able to grab any logs from the machine or booted into the recovery mode to see whether the the internal graphics adapter is still recognised (lspci)...of course using an external monitor?