6.8.12-11-pve was released for both PVE and PBS, there were some changes to the ABI.
https://git.proxmox.com/?p=pve-kernel.git;a=shortlog;h=refs/heads/bookworm-6.8
https://git.proxmox.com/?p=pve-kernel.git;a=shortlog;h=refs/heads/bookworm-6.8
ABI stands for Application Binary Interface. It defines the low-level interface between the kernel and its modules (such as device drivers), specifying how compiled code interacts with the kernel at the binary level. This includes details like register usage, memory layout, calling conventions, and symbol versions of exported kernel functions and variables