[CentOS] IOMMU and kernel (solved?)

Fri Apr 3 18:55:12 UTC 2020
Simon Matter <simon.matter at invoca.ch>


> I think i might have solve it.
> For some reason grub2-mkconfig doesnt work.  (Have no idea why)

Is this on CentOS 7?

Well, yes, I remember that it didn't work for me when I installed new
servers one or two years ago, that was with CentOS 7 and they were my
first EFI installs.

> I manage to solve it with grubby.
> sudo grubby --args="intel_iommu=on" --update-kernel=ALL
> For some reason it works. I dont know if it works if my kernel gets
> upgraded.

I have restored the original configs after messing with grub2-mkconfig and
only used kernel installs to further modify grub config. That way it has
always worked for me. And I was a bis scared by the whole EFI, grub2 and
everything around it because I felt I don't really understand how it all
interacts in detail.