shim-signed depends unsatisfiable when installing grub-xen on ubuntu 24.04

[Hadmut Danisch]

Hi,

wanted to install xen on a freshly setup 24.04 server:

apt-get install grub-xen

Reading package lists...
Building dependency tree...
Reading state information...
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 shim-signed : Depends: grub-efi-amd64-signed (>= 1.191~) but it is not going to be installed or
                        grub-efi-arm64-signed (>= 1.191~) but it is not installable or
                        base-files (< 12.3) but 13ubuntu10 is to be installed
               Depends: grub-efi-amd64-signed (>= 1.187.2~) but it is not going to be installed or
                        grub-efi-arm64-signed (>= 1.187.2~) but it is not installable
E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.

[Mate Kukri (mkukri)]

Ah this is actually an apt UX problem, what it meant to say is that shim-signed and grub-efi-amd64-signed and are not co-installable with grub-xen.

I am not sure what are you trying to accomplish with grub-xen, as I don't think it is usually needed for installing Xen

[Hadmut Danisch (hadmut)]

Isn't grub-xen required to start xen, since xen is (in contrast to other virtualization methods) a layer underneath the regular operating system and thus needs to be bootet before the operating system, i.e. from grub?

[Son Luong (sluongng)]

I am also having trouble with this exact error when trying to remove python 3.11.
I am on 23.10 and trying to upgrade to 24.04.

```
~> sudo apt remove python3.11
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 shim-signed : Depends: grub-efi-amd64-signed (>= 1.191~) but it is not going to be installed or
                        grub-efi-arm64-signed (>= 1.191~) but it is not installable or
                        base-files (< 12.3)
               Depends: grub-efi-amd64-signed (>= 1.187.2~) but it is not going to be installed or
                        grub-efi-arm64-signed (>= 1.187.2~) but it is not installable
               Depends: grub2-common (>= 2.04-1ubuntu24) but it is not going to be installed
E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.
exit 100
```