Today, after a reboot, my laptop (Fedora 25) cannot boot and only shows grub prompt. I have no idea what happened or what changes I made to the system.
Here is how I fixed it:
ls command to find the partition that has kernel images,
shows something like:
2. select kernel image and boot
(I have UEFI enabled and use lvm partition)
Because of lvm partitionm, I need to specify where the root is. My root partition is mapped as
linuxefi /vmlinuz-4.10.5-200.fc25.x86_64 root=/dev/fedora/root ro
After successfully login, we need regenerate grub.cfg. (for unknown reason, my grub.cfg was an empty file…)
grub2-mkconfig -o /boot/efi/EFI/fedora/grub.cfg
That’s all and everything looks good now.