Bug 1523275

According to dmesg output there's something wrong with kernel modules. What happens when you enter following as root:

modprobe dm-crypt

?

I have found the problem. Anaconda generate grub.cfg with kernel FC26 and label Fedora 27 and used Fedora 27 system.

#tune2fs -l /dev/sda7 | grep -e UUID -e name
Filesystem volume name:   FEDORA27
Filesystem UUID:          975f0abb-5a7a-4a55-baec-7aa92956c81e

# tune2fs -l /dev/sda6 | grep -e UUID -e name
Filesystem volume name:   FEDORA26
Filesystem UUID:          1b8c6b3b-3ca9-474f-8364-49f4d21cd981

menuentry 'Fedora (4.13.13-200.fc26.x86_64) 27 (Workstation Edition)' --class fedora --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-4.13.13-200.fc26.x86_64-advanced-975f0abb-5a7a-4a55-baec-7aa92956c81e' {
	load_video
	set gfxpayload=keep
	insmod gzio
	insmod part_msdos
	insmod ext2
	set root='hd0,msdos3'
	if [ x$feature_platform_search_hint = xy ]; then
	  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos3 --hint-efi=hd0,msdos3 --hint-baremetal=ahci0,msdos3 --hint='hd0,msdos3'  3d2fbccd-1c3d-4731-a95b-4c1585ffa79f
	else
	  search --no-floppy --fs-uuid --set=root 3d2fbccd-1c3d-4731-a95b-4c1585ffa79f
	fi
	linux16 /vmlinuz-4.13.13-200.fc26.x86_64 root=UUID=975f0abb-5a7a-4a55-baec-7aa92956c81e ro rhgb quiet
	initrd16 /initramfs-4.13.13-200.fc26.x86_64.img
}

The correct parameter to start with Fedora 27 are in the 3th rules 
menuentry 'Fedora (4.13.9-300.fc27.x86_64) 27 (Workstation Edition)' --class fedora --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-4.13.9-300.fc27.x86_64-advanced-975f0abb-5a7a-4a55-baec-7aa92956c81e' {
	load_video
	set gfxpayload=keep
	insmod gzio
	insmod part_msdos
	insmod ext2
	set root='hd0,msdos3'
	if [ x$feature_platform_search_hint = xy ]; then
	  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos3 --hint-efi=hd0,msdos3 --hint-baremetal=ahci0,msdos3 --hint='hd0,msdos3'  3d2fbccd-1c3d-4731-a95b-4c1585ffa79f
	else
	  search --no-floppy --fs-uuid --set=root 3d2fbccd-1c3d-4731-a95b-4c1585ffa79f
	fi
	linux16 /vmlinuz-4.13.9-300.fc27.x86_64 root=UUID=975f0abb-5a7a-4a55-baec-7aa92956c81e ro rhgb quiet LANG=it_IT.UTF-8
	initrd16 /initramfs-4.13.9-300.fc27.x86_64.img
}

I have change the UUID in Fedora 26 rules from =975f0abb-5a7a-4a55-baec-7aa92956c81e to 1b8c6b3b-3ca9-474f-8364-49f4d21cd981
Now works perfectly.

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