Felix, I'm back on track! I found what triggered this horrible problem :)

At some point I added the qemu-binfmt-service-type to my system. I
copied a snipped from the manual and finally "adjusted" it to this:

```
(define %qemu-service
  (service qemu-binfmt-service-type
           (qemu-binfmt-configuration
            (platforms (lookup-qemu-platforms "aarch64" "x86_64")))))
```

I don't know much about quem and I thought, well let's choose the
"aarch64" and "x86_64" qemu platforms on which I run Guix, and maybe
re-use this service on multiple machines.

My Guix system runs on the aarch64 architecture. It turns out that
having "aarch64" in lookup-qemu-platforms causes the "Too many levels of
symbolic links" error. As soon as I remove it, everything is good again.

Now, maybe it does not even makes sense to add "aarch64" to that list,
but I think it should not fail that catastrophical. I still don't know
which symlink was causing this issue, though.

That's where I am. Just happy that I survived my first serious Guix
crash. :)

Thanks for your help so far,

Roman

Felix Lechner <felix.lechner@lease-up.com> writes:

> Hi Roman,
>
> On Fri, Mar 10, 2023 at 7:32 AM Roman Scherer
> <roman.scherer@burningswell.com> wrote:
>>
>> Right now I rolled back to generation 53, which is still
>> working.
>
> Great!
>
>> Is it correct to look for the problematic files in the directory to
>> which system-54-link links to?
>
> Yes, probably. Unfortunately, profiles are large bundles of symbolic
> links, so finding the offending cycle may not be easy.
>
>> Generation 54 is the broken one, which does boot up, but
>> logging in fails with the too many levels of symbolic link issue.
>
> Since the issue occurs at login, there may also be a bad interaction
> with your user profile. What if you log in as another user?
>
>> I run the problematic commands from that directory and they seem to run
>> from the non-broken system
>
> My prime list of suspects include something like a system-wide Bash
> profile (or whichever shell you use).
>
>> I'm thinking of re-installing my system completely.
>
> Please don't do that. It is not necessary.
>
> Instead, you can delete generation 54 and try again. Make sure to
> 'guix pull' before reconfiguring again.
>
>> Do I have any other option, even an unsupported one?
>
> Please post the config.scm for your generation 53, plus a diff to
> generation 54. You find copies via 'guix system describe'. It may also
> be helpful to attach your home.scm, if you use Guix Home.
>
> Together with the changes in Guix since the commit on which generation
> 53 is based, we will find the issue. The process is more or less
> deterministic.
>
> Please keep up hope. All needed software is already installed. Guix
> has extraordinary ways to recover—even though they can be hard to
> figure out.
>
> Kind regards
> Felix