These messages are related to the GPU being put into a power sleep state, and not being able to be activated in time for the VM.
vfio-pci 0000:02:00.0: Unable to change power state from D3cold to D0, device inaccessible
vfio-pci 0000:02:00.1: Unable to change power state from D3cold to D0, device inaccessible
Try on the Host VM:
1. Kernel module
In /etc/default/grub add to options:
disable_idle_d3=1
2. Bind the GPU early. and stop idle 3D
Create /etc/modprobe.d/vfio-pci.conf:
# RTX 5090 GPU (10de:2b85) + Audio (10de:22e8)
# Bind both functions to vfio-pci and prevent runtime D3 (D3cold)
options vfio-pci ids=10de:2b85,10de:22e8 disable_vga=1 disable_idle_d3=1
3. Reinforce power management rules
Create /etc/udev/rules.d/99-vfio-gpu-pm.rules:
# Force RTX 5090 functions to stay in D0 and block deepest sleep
ACTION=="add", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{device}=="0x2b85", ATTR{power/control}="on", ATTR{d3cold_allowed}="0"
ACTION=="add", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{device}=="0x22e8", ATTR{power/control}="on", ATTR{d3cold_allowed}="0"
4. Apply and Reboot
update-initramfs -u
udevadm control --reload-rules
udevadm trigger -s pci
update-grub
reboot