1.
Check these for incompatible values. The follow example is based on
UEFI with Secure Boot enabled, so hibernation isn't possible with
Fedora kernels.
[root@f23s ~]# mokutil --sb-state
SecureBoot enabled
[root@f23s ~]# cat /sys/power/state
freeze mem
[root@f23s ~]# cat /sys/power/disk
[disabled]
2.
cat /proc/meminfo
MemTotal < 0.98 * SwapFree = true
So memory must be 98% or less than swap free, not swap partition size.
3.
You're best off using UUID. It needs to be in /etc/fstab
UUID=theuuidforswap swap swap 0 0
4.
In /etc/default/grub GRUB_CMDLINE_LINUX="resume=UUID=theuuidofswap"
grub2-mkconfig -o /boot/efi/EFI/fedora/grub.cfg ## for efi systems
and just /boot/grub2/grub.cfg for BIOS
5.
journalctl -b | grep PM
Check current and prior boots for hibernate hibernation related
messages. For example:
https://paste.fedoraproject.org/360483/
In my case the image is found but fails to resume anyway likely due to
a firmware + kernel bug.
Chris Murphy