#1070762 debos: unhelpful error message "Modules path couldn't be determined"

Package:
debos
Source:
debos
Description:
Debian OS builder
Submitter:
Helmut Grohne
Date:
2026-05-13 02:45:19 UTC
Severity:
normal
Tags:
#1070762#5
Date:
2024-05-08 15:59:08 UTC
From:
To:
Hi,

I was trying to use debos and all that it told me was:

| Modules path couldn't be determined

This is not helpful. After digging into code I eventually figured that
when it says "modules" it measn "Linux kernel modules". This is not
evident from the context. Moreoever, it eventually became clear that the
module it was missing was 9pnet_virtio. If that name had been included
in the error message, it would have been immediately obvious to me that
the cause was using a -cloud kernel as -cloud kernels lack 9p
functionality (see #955232). While debos recommends a non-cloud kernel
and the non-cloud kernel even got installed, the additional presence of
a -cloud kernel image meant that grub would prefer booting that.

I hope this is sufficient reason to improve the error message. Thanks
for considering.

Helmut

#1070762#10
Date:
2026-04-19 17:45:52 UTC
From:
To:
Hi Helmut,
Thanks for reporting and sorry for the delay. I've just managed to get some
time to do some triage on this package.

You're right. That's a pretty useless error message! I've proposed a patch upstream
to make the error more verbose: https://github.com/go-debos/fakemachine/pull/298

The error will read something like: "fakemachine: kernel module '9p' not found for kernel '6.19.12+deb14-amd64'"

It will trickle down eventually into debian once it is merged.


Cheers!

Chris

#1070762#17
Date:
2026-04-20 19:29:28 UTC
From:
To:
Hi,

Just mentioning that https://github.com/go-debos/fakemachine/pull/298 was merged upstream and will
be in the next fakemachine/debos release, probably in the next couple of months.


Cheers!

Chris