I think what happened was that when we made the changes for the new grub2 subpackages in commit 5d204bd21e28b3624ff258e03ce79c9c3e91fbb9 it lost the requirement for grub2-pc (which pulls in grub2-pc-modules) because we're not pulling in the main grub2 package anymore. The same goes for grub2-efi-modules.

Well, we shouldn't ever need grub2-efi-*-modules, because grub2-efi-* have pre-built grub$ARCH.efi images in them, so there's no need to run grub2-install on UEFI. I think we just need to add "installpkg grub2-${basearch}" for the non-efi cases.

(In reply to Peter Jones from comment #4)
> Well, we shouldn't ever need grub2-efi-*-modules, because grub2-efi-* have
> pre-built grub$ARCH.efi images in them, so there's no need to run
> grub2-install on UEFI. I think we just need to add "installpkg
> grub2-${basearch}" for the non-efi cases.

I'm not sure what to do here. Nothing provides grub2-x86_64, and the rpm that these files are in only provides:

grub2-pc-modules = 1:2.02-0.65.el7_4.2

Please excuse me;  I reported 'grub2-install: error: /usr/lib/grub/x86_64-efi/modinfo.sh doesn't exist.', here: https://bugzilla.redhat.com/show_bug.cgi?id=1277227 in '15

At the time,  /usr/lib/grub/i386-pc/modinfo.sh existed (in 7.1 1403).  

Now, both are missing (x86_64-efi and i386-pc).  The main purpose of this comment is to link them together.   

1277227 was re-opened but somehow closed again?   Does this replace that?  
 
FWIW, there are issues upgrading from f26 to f27 that appear related.  There's sill an issue in f28, too.  It's missing both as well.

IMHO, much of this stems from the inclusion of the 'prebaked', custom grubx86.efi

Another use case that will follow, and break on all of the RedHat variants, is moving /boot to a cryptodisk.  

grub2-install should work as advertised upstream and be included in preboot, squashfs, etc.

et cetera

(In reply to Peter Jones from comment #4)
> Well, we shouldn't ever need grub2-efi-*-modules, because grub2-efi-* have
> pre-built grub$ARCH.efi images in them, so there's no need to run
> grub2-install on UEFI. I think we just need to add "installpkg
> grub2-${basearch}" for the non-efi cases.

Respectfully, there are multiple reasons people (like me) will want to run grub2-install on UEFI.

With articles going out like this, https://dustymabe.com/2015/07/06/encrypting-more-boot-joins-the-party/ (for BIOS).  

All newer machines are UEFI.  The same can be done (move /boot to an encrypted volume) as long as the proper grub2 modules are there.  The fact that they aren't included in the RedHat versions of grubx86.efi prompts the necessity to be able to run grub2-install on UEFI, for anyone wanting a more secure system.

*** Bug 1626269 has been marked as a duplicate of this bug. ***

Ok, I took another look at this with 7.9 today, adding the grub2-*-module packages to the boot.iso
On UEFI running grub2-install now complains about not being able to find the EFI directory.
On BIOS it complains 'error: unable to identify a filesystem in hostdisk//dev/sda; safety check can't be performed.'

So as far as I can see, even with the modules included, it isn't useful. The other issue is that this adds about 12M to the rootfs and on some architectures we're pretty close to being too large for a CD, so we need to be very careful about what we add.

Unless someone can provide a really good reason to add this, and demonstrate that it solves an actual problem for them, I'm going to close this.