It's difficult to find the pointer that could explain the correct use of
the options and their combinations.
This sort of advice wouldbe wonderful if it wereincluded in the spec,
which as of now is too technical for mere mortals:
http://www.mjmwired.net/kernel/Documentation/x86_64/boot-options.txt
I'm not surprised that end user cannot know what combination of options
make or does not make sense. I'll try at next boot with plain:
iommu=memaper=3
Thank you,
Jari
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