The Linux 6.1 backports are built with udebs disabled, but it would
be useful to actually have them built and available even though
the default Bullseye installer uses 5.10:

I tried to build a Bullseye netboot image with an initrd including
the 5.10 kernel modules and the Linux 6.1 kernel for Bullseye.

Such a d-i image boots fine, but then anna attempts to fetch matching
udebs from the Debian repos and since src:linux-6.1 build with udebs
disabled the installer aborts.

Cheers,
        Moritz