Intel VMD driver required to support NVMe SSDs on Intel Xeon SP
I was wondering why my brand new NVMe SSDs where not listed in lspci neither on XenServer nor XCP-ngit, while some quick tests on CentOS 7 showed they are working properly there.
Some further investigations and after comparing several kernel versions, it turned out that current Intel Xeon platforms (Skylake-E etc.) require a driver for the internal VMD host bridge .
A research on kernel.org showed, that VMD is mainline since Linux 4.5. 
and CentOS 7.3 backported the driver in 2016 with kernel 3.10.0-514.
Unfortunately XenServer/XCP-ng kernel 4.4.52 is still missing this particular driver.
Do you see any chance to backport support for VMD with current versions of XenServer/XCP-ng as well?
This is in theory possible, but not trivial. Usually @r1 or @stormi can give you good advice on how to try to do it yourself (unlike XS, we are open to "do it yourself, here is some tools" philosophy).
Also in theory, XS 7.6 should be out in weeks (4 or 5 max? if they stick to their plan), with probably a more recent kernel. IDK which option will be faster.