ayaseen, many users are running Linux on Threadripper, but since I know almost nothing about Linux, I cannot answer your question. I suggest you do some searching on the Internet and Linux forums. Officially AMD supports only W10 x64 version 1607 of higher. Enjoy, John.
Please forgive me.
You have to ask the question differently. Not: "Is fedora 28 supported by Amd threadripper 1950x"
The correct question is: "Is Amd threadripper 1950x supported by Fedora 28".
You need to know that the Linux kernel supports the Zen architecture. But only, and only if this is explicitly selected in the kernel.
But that does not make a distribution. Not Red Hat, not Fedora, not Debian, not * buntu, not SLES, not openSuse, no distribution makes this support in the kernel. If you want this support, you have to build your own kernel.
All distributions use only a general x86_64 CPU function.
These distributions often have "older" kernels. Recently with kernel version 4.15 came with amdgpu for HDMI (HDMI audio) and DP working graphics application in the kernel. Which kernel version do you use with Fedora28?
And what do you mean by KVM ?? Keyboard-Video-Mouse? Or kernel-based-virtual-machine?
Keyboard Video Mouse is evdev related. So it belongs to the distribution. (Https://en.wikipedia.org/wiki/Evdev)
Kernel-based virtual machine is either a setting in UEFI/Bios or belongs to the distribution. (Https://en.wikipedia.org/wiki/Kernel-based_Virtual_Machine).
Each distribution has its own specifics here. All this has nothing to do with AMD.
Or Intel, or ARM.
With your questions, you must contact the Fedora Forum.