Since people don't care to read whole discussion I'm going to repeat myself here every few posts.
It is not caused by Ubuntu 17.10
It is general Linux issue (I was Antergos user when it hit me)
Solution is to physically replace NVRAM chip and reflash it with the content from the old one.
Workaround - use rEFInd as I've posted the step-by-step guide at Lenovo site.
Since people don't care to read whole discussion I'm going to repeat myself here every few posts.
It is not caused by Ubuntu 17.10
It is general Linux issue (I was Antergos user when it hit me)
Solution is to physically replace NVRAM chip and reflash it with the content from the old one.
Workaround - use rEFInd as I've posted the step-by-step guide at Lenovo site.
Marcin78