The  ODroid XU4 series are a family of credit card-sized ARM based single board computer (SBC). Fedora 27 supports the the XU4, and closely related variant HC1 in Fedora 27 without any requirement of third party kernels or scripts to adjust official images. This documentation describes how to get started, and (will) include a Frequently Asked Questions (FAQ) about what is supported and what is not.
Some of the Fedora community have barely restrained  hostility to Exynos devices
- From my point of view the devices are "best effort", I personally don't have any devices to test, the Odroid manufacturers generally don't give a shit about anything upstream and no one in the community has stepped up to be the maintainer of the (Exynos) devices
This of course also represents an opportunity for developers to step up, and to dispel that attitude with documentation and stabilization work, such that this Caveat might be removed
We initially only seek to support the ODroid XU4 and HC1.
- An ODroid XU4 or HC1
- Good quality SD Card (eLinux hosts a compatibility list). ODroid also sells such, but shipping costs are non-trivial from Korea; Amazon also stocks a partial line of current production ODroid kit
- A USB keyboard
- A hefty power supply. You'll want at least 2A and 2.5A is preferred to avoid mysterious and hard to diagnose power 'current droop' failure modes
- HDMI Monitor, or TV with an HDMI input (optional as to the HC1, which is 'headless')
- A USB mouse (optional)
For preparation of the SD card:
- Computer running any modern operating system; SD card writing software
- SD card reader / writer device (usually an USB device, but an 'in-chassis' adapter has been shown to also work fine)
On a Odroid HC1 with kernel 4.15.0-0.rc0.git6.1.fc28.armv7hl  with on-board network (USB-3bus based) and the ssd (USB-2 bus based SATA ... the HC1 has multiple USB buses) is working
Background on the fix
From the Fedora mailing list:
- http://www.spinics.net/lists/arm-kernel/msg606525.html 
- So today must be your lucky day, while waiting for images to download I was browsing the ARM kernel list and noticed the exynos pull request for 4.15  and low and behold there's a fix headed upstream for the usb3 issues and it applied cleanly to 4.13/4.14 so that should be fixed in 4.13.7 which might make F-27 GA because I'm such a nice individual. Only took them 7 kernel releases to fix it!
- The system still requires the 'cpuidle.off=1' argument on the "append" line of the 'extlinux.conf' file to boot