Passthrough with cuda 11.2.2 and nvidia driver 460 does not work at all on Debian

Hello to everyone.

I’m trying to pass thru my graphic card,nvidia RTX 2080 ti from the host os (Ubuntu 21.10) to the guest os (Debian 10) with qemu + kvm. For a specific technical reason,I should install the nvidia driver 460 and not 470 and cuda 11.2.2. So,I’ve tried with Debian 10 and even Debian 11,using the procedure explained below,but it didn’t work. Instead,it works if I use Debian 11 as guest os + cuda 11.4 and the nvidia driver 470. Can someone explain the reason ?

wget https://developer.download.nvidia.com/compute/cuda/11.2.2/local_installers/cuda-repo-debian10-11-2-local_11.2.2-460.32.03-1_amd64.deb  

sudo dpkg -i cuda-repo-debian10-11-2-local_11.2.2-460.32.03-1_amd64.deb  

sudo apt-key add /var/cuda-repo-debian10-11-2-local/7fa2af80.pub  

sudo add-apt-repository contrib  

sudo apt-get update  

sudo apt-get -y install cuda  

nano /root/.bashrc  

export PATH="/usr/local/cuda-10.1/bin:$PATH" 

export LD_LIBRARY_PATH="/usr/local/cuda/lib64:$LD_LIBRARY_PATH" 

source .bashrc

REBOOT

nvidia-smi

Unable to determine the device handle for gpu 0000:05:00.0 : unknown error.