Comment # 14 on bug 1220276 from Michael Chang

(In reply to Lukas Ocilka from comment #11)
> Created attachment 873339 [details]
> OS Prober log

As anticipated, the utilization of blscfg [1] is causing os-prober to be unable
to extract the menu entry. Even if it were able to do so, our grub cannot
currently handle it, given that the bls patch is currently specific to Fedora.
The situation is further complicated when bls fragments are placed in a private
partition from a different source.

It's worth noting that this is not a bug but rather a missing feature.

[1]

> Mar 08 09:16:49 localhost.localdomain 40grub2[25288]: debug: parsing: ### BEGIN /etc/grub.d/10_linux ###
> Mar 08 09:16:49 localhost.localdomain 40grub2[25289]: debug: parsing: insmod part_gpt
> Mar 08 09:16:49 localhost.localdomain 40grub2[25290]: debug: parsing: insmod ext2
> Mar 08 09:16:49 localhost.localdomain 40grub2[25291]: debug: parsing: search --no-floppy --fs-uuid --set=root 6e49bf93-019b-454b-a5f3-8c8d52193323
> Mar 08 09:16:49 localhost.localdomain 40grub2[25292]: debug: parsing: insmod part_gpt
> Mar 08 09:16:49 localhost.localdomain 40grub2[25293]: debug: parsing: insmod fat
> Mar 08 09:16:49 localhost.localdomain 40grub2[25294]: debug: parsing: search --no-floppy --fs-uuid --set=boot 963E-202E
> Mar 08 09:16:49 localhost.localdomain 40grub2[25295]: debug: parsing:
> Mar 08 09:16:49 localhost.localdomain 40grub2[25296]: debug: parsing: # This section was generated by a script. Do not modify the generated file - all changes
> Mar 08 09:16:49 localhost.localdomain 40grub2[25297]: debug: parsing: # will be lost the next time file is regenerated. Instead edit the BootLoaderSpec files.
> Mar 08 09:16:49 localhost.localdomain 40grub2[25298]: debug: parsing: #
> Mar 08 09:16:49 localhost.localdomain 40grub2[25299]: debug: parsing: # The blscfg command parses the BootLoaderSpec files stored in /boot/loader/entries and
> Mar 08 09:16:49 localhost.localdomain 40grub2[25300]: debug: parsing: # populates the boot menu. Please refer to the Boot Loader Specification documentation
> Mar 08 09:16:49 localhost.localdomain 40grub2[25301]: debug: parsing: # for the files format: https://systemd.io/BOOT_LOADER_SPECIFICATION/.
> Mar 08 09:16:49 localhost.localdomain 40grub2[25302]: debug: parsing:
> Mar 08 09:16:49 localhost.localdomain 40grub2[25303]: debug: parsing: # The kernelopts variable should be defined in the grubenv file. But to ensure that menu
> Mar 08 09:16:49 localhost.localdomain 40grub2[25304]: debug: parsing: # entries populated from BootLoaderSpec files that use this variable work correctly even
> Mar 08 09:16:49 localhost.localdomain 40grub2[25305]: debug: parsing: # without a grubenv file, define a fallback kernelopts variable if this has not been set.
> Mar 08 09:16:49 localhost.localdomain 40grub2[25306]: debug: parsing: #
> Mar 08 09:16:49 localhost.localdomain 40grub2[25307]: debug: parsing: # The kernelopts variable in the grubenv file can be modified using the grubby tool or by
> Mar 08 09:16:49 localhost.localdomain 40grub2[25308]: debug: parsing: # executing the grub2-mkconfig tool. For the latter, the values of the GRUB_CMDLINE_LINUX
> Mar 08 09:16:49 localhost.localdomain 40grub2[25309]: debug: parsing: # and GRUB_CMDLINE_LINUX_DEFAULT options from /etc/default/grub file are used to set both
> Mar 08 09:16:49 localhost.localdomain 40grub2[25310]: debug: parsing: # the kernelopts variable in the grubenv file and the fallback kernelopts variable.
> Mar 08 09:16:49 localhost.localdomain 40grub2[25311]: debug: parsing: if [ -z "${kernelopts}" ]; then
> Mar 08 09:16:49 localhost.localdomain 40grub2[25312]: debug: parsing: set kernelopts="root=UUID=9bdb61d9-f5d8-4154-95bc-7c3f12f66b9a ro rootflags=subvol=root rhgb quiet "
> Mar 08 09:16:49 localhost.localdomain 40grub2[25313]: debug: parsing: fi
> Mar 08 09:16:49 localhost.localdomain 40grub2[25314]: debug: parsing:
> Mar 08 09:16:49 localhost.localdomain 40grub2[25315]: debug: parsing: insmod blscfg
> Mar 08 09:16:49 localhost.localdomain 40grub2[25316]: debug: parsing: blscfg
> Mar 08 09:16:49 localhost.localdomain 40grub2[25317]: debug: parsing: ### END /etc/grub.d/10_linux ###