Failure to passthrough PCIe after update Proxmox (IOMMU cannot be enable)

[kaleaves]

Dear all

Recently, I updated my Proxmox from 7.1.6 to 7.3.6 successfully. However the GPU disabled then I try to update the GRUB(it work in 7.1.6) with

GRUB_DEFAULT=0
GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet amd_iommu=on iommu=pt video=vesafb:off video=efifb:off video=simplefb:off"
GRUB_CMDLINE_LINUX=""

next

update-grub

show

root@pve:~# update-grub
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-5.15.85-1-pve
Found initrd image: /boot/initrd.img-5.15.85-1-pve
Found linux image: /boot/vmlinuz-5.13.19-6-pve
Found initrd image: /boot/initrd.img-5.13.19-6-pve
Found linux image: /boot/vmlinuz-5.13.19-2-pve
Found initrd image: /boot/initrd.img-5.13.19-2-pve
Found memtest86+ image: /boot/memtest86+.bin
Found memtest86+ multiboot image: /boot/memtest86+_multiboot.bin
Warning: os-prober will not be executed to detect other bootable partitions.
Systems on them will not be added to the GRUB boot configuration.
Check GRUB_DISABLE_OS_PROBER documentation entry.
Adding boot menu entry for UEFI Firmware Settings ...
done

Then I checked IOMMU is still not work.

Should I remove the old kernal or just leave it? What should I do?

Many Thx

Update 2/3/2023
PC Spec:
CPU: AMD 5700G
Motherboard: Asrock B550
GPU: ASUS GTX2080ti 12GB
Ram: 32GB

 

[Chris]

Hi,
did you reboot after upgrading the system to the latest version? Also please give more details about what hardware you are running on and what exactly is not working.

What is the output of:

• cat /proc/cmdline
• lsmod | grep -E '(iommu|vfio)'
• dmesg | grep -e DMAR -e IOMMU -e AMD-Vi

Make sure to correctly configure the modules in /etc/modules and rebuild the initramfs by running update-initramfs -u -k all

For details please refer to this wiki article https://pve.proxmox.com/wiki/PCI(e)_Passthrough

 

[leesteken]

GRUB_CMDLINE_LINUX_DEFAULT="quiet amd_iommu=on iommu=pt video=vesafb:off video=efifb:off video=simplefb:off"

If you have an AMD CPU then you don't need amd_iommu=on because it is on by default. You just need to fully enable it in the BIOS (IOMMU to Enabled, not just Auto and maybe enable ACS and some other related stuff..).
Additionally,video=vesafb:off video=efifb:off video=simplefb:off does nothing anymor since kernel 5.15 and you need this work-around: initcall_blacklist=sysfb_init, if you are passing through a GPU that is used during boot of the Proxmox system.

 

[kaleaves]

Problem solved! Big thank to you guys!
GPU can work find now. I did you said to remove the unnecessary argument in GRUB.

If you have an AMD CPU then you don't need amd_iommu=on because it is on by default. You just need to fully enable it in the BIOS (IOMMU to Enabled, not just Auto and maybe enable ACS and some other related stuff..).
Additionally,video=vesafb:off video=efifb:off video=simplefb:off does nothing anymor since kernel 5.15 and you need this work-around: initcall_blacklist=sysfb_init, if you are passing through a GPU that is used during boot of the Proxmox system.