Environment:

- Proxmox VE 9.1.9, kernel 6.17.9-1-pve

- TrueNAS 25.10.3 working fine, upgraded to 25.10.4

- VM config: Q35, OVMF (UEFI), VirtIO-SCSI-PCI controller, 8GB RAM, 2 cores (host type)

- QEMU version: 10.1.2 (pve-qemu-kvm_10.1.2-7)

Problem:

After updating to 25.10.4, the system drops to initramfs shell with:

“cannot import ‘boot-pool’: no such pool available”

Root cause identified:

- Kernel 6.12.91 appears to not initialize virtio-scsi subsystem during early boot in QEMU/KVM environment

- Inside initramfs, /dev/ has NO disk devices (no /dev/sda, /dev/vda, etc.)

- zpool import returns “no pools available”

- The virtio-scsi disk is completely invisible to the kernel 6.12.91 initramfs

- Reverting to 25.10.3 (kernel 6.12.33) boots perfectly with identical VM config

Investigation:

- initrd contains virtio_scsi.ko module - Regenerating initrd via chroot did not resolve the issue

- Tried virtio-scsi-pci, virtio-scsi-single controllers - same result

- Tried SATA and IDE controllers - disk still not visible

- initrd format is plain cpio (not compressed), modules present but not loaded

- /dev/ contains only ttys, mem, random, urandom - no block devices whatsoever

- Problem persists regardless of SCSI controller type or disk bus type

- Similar issue reported with 25.10.2 on Proxmox: Upgrade to 25.10.2 fails on Proxmox VM

Workaround:

- zectl activate 25.10.3 from initramfs (after manually importing pool)

- OR revert boot environment from Proxmox host

Expected: 25.10.4 should boot with the same VM hardware config as 25.10.3