Voilà ce que me retourne la commande :
grub2-mkconfig -o /boot/efi/EFI/fedora/grub.cfg
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-4.6.4-301.fc24.x86_64
Found initrd image: /boot/initramfs-4.6.4-301.fc24.x86_64.img
Found linux image: /boot/vmlinuz-4.5.5-300.fc24.x86_64
Found initrd image: /boot/initramfs-4.5.5-300.fc24.x86_64.img
Found linux image: /boot/vmlinuz-0-rescue-f4e4ce114f674045bb6f06750a2b2785
Found initrd image: /boot/initramfs-0-rescue-f4e4ce114f674045bb6f06750a2b2785.img
done
Et après je n'arrive pas accéder à grub.cfg mais je vais essayer