Bug#1114894: OS-Prober generates not running entries for Debian 12

[Pascal Hambourg]

On 16/09/2025 at 22:14, Debian wrote:
> 
> A new update-grub is called in Debian 13 and the syslog output is attached.
> Hopefully this will help.

It looks like /dev/sdb2 has the wrong /boot/grub/grub.cfg which has menu 
entries for /dev/sdb1 ('Debian GNU/Linux 11 SSD', 'Linux 
5.10.0-35-amd64'). This is why linux-boot-prober cannot match the menu 
entries in this file with the 6.1.0-39 kernel image in the partition. It 
also looks like /vmlinuz and /initrg.img are real files instead of the 
usual symlinks pointing to the files in /boot.

Try to boot into bookworm on /dev/sdb2, run update-grub, then reboot on 
trixie and run update-grub.