[SOLVED] x2apic: IRQ remapping doesn't support X2APIC mode

winyiday

New Member
Nov 21, 2022
7
0
1
Hello, I encountered this problem when using proxmox-ve_7.2-1.

root@E:~# dmesg | grep -e DMAR -e IOMMU
[ 0.038236] DMAR: IOMMU enabled
root@E:~# dmesg | grep 'remapping'
[ 0.105871] x2apic: IRQ remapping doesn't support X2APIC mode

My computer: Cpu:g6500t Matherboard:Ausu b460m plus(wifi)

The motherboard does not have the option to disable x2apic.
what should I do? Change the motherboard? or use the old version of PVE 6?
 
does it actually cause any problem?
can you post the full 'dmesg' output?

edit: you can also try to add 'nox2apic' to the kernel commandline
 
  • Like
Reactions: winyiday
does it actually cause any problem?
can you post the full 'dmesg' output?

edit: you can also try to add 'nox2apic' to the kernel commandline
While it does not cause critical system errors, PCEI passthrough and certain functions do not work.

Add: PCI device
IOMMU not detected, please activate it. See the documentation for more information.

5AJpbKC.png


my stpes:
Bash:
root@PVE:~# uname -a >>>
Linux PVE 5.15.74-1-pve #1 SMP PVE 5.15.74-1 (Mon, 14 Nov 2022 20:17:15 +0100) x86_64 GNU/Linux

root@PVE:~# apt update && apt dist-upgrade √

vim /etc/default/grub >>>
GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on iommu=pt nox2apic intremap=no_x2apic_optout  video=efifb:off,vesafb:off"[/ICODE]

root@PVE:~# update-grub             >>>
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-5.15.74-1-pve
Found initrd image: /boot/initrd.img-5.15.74-1-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 ...

root@PVE:~# dmesg | grep -e DMAR -e IOMMU >>>
[0.039469]DMAR: IOMMU enabled

root@PVE:~# cat << EOF >> /etc/modules          >>>
vfio
vfio_iommu_type1
vfio_pci
vfio_virqfd
EOF

root@PVE:~# update-initramfs -u          >>>
update-initramfs: Generating /boot/initrd.img-5.15.74-1-pve
Running hook script 'zz-proxmox-boot'..
Re-executing '/etc/kernel/postinst.d/zz-proxmox-boot' in new private mount namespace..
No /etc/kernel/proxmox-boot-uuids found, skipping ESP sync.

root@PVE:~# reboot √

root@PVE:~# dmesg | grep 'remapping' >>>
[0.119499] x2apic: IRQ remapping doesn't support X2APIC mode

root@PVE:~# dmesg >> log.txt
 
Last edited:
did you try to disable x2apic with the kernel commandline switch i mentioned? i don't see it in your logs
 
did you try to disable x2apic with the kernel commandline switch i mentioned? i don't see it in your logs
I try add nox2apic or intremap=no_x2apic_optout or both in
/etc/default/grub

not working

Bash:
GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on iommu=pt nox2apic intremap=no_x2apic_optout video=efifb:off,vesafb:off"
root@PVE:~# dmesg | grep 'remapping'             >>>

root@PVE:~# dmesg >>log2

Shouldn't I add it here?
PCI(e) can't passthrough
 
Last edited:
Last edited:
  • Like
Reactions: winyiday
did you run update-grub afterwards? check https://pve.proxmox.com/wiki/Host_Bootloader#sysboot_edit_kernel_cmdline

edit: i saw now that it is enabled in the cmdline so that works at least

are you sure you enabled iommu/vt-d in the bios?
update-grub ✔ update-initramfs -u ✔ reboot ✔
Code:
【1】no_x2apic:  dmesg | grep 'remapping'     >>>


【2】normal   :dmesg | grep 'remapping'     >>>
[    0.119499] x2apic: IRQ remapping doesn't support X2APIC mode


BIOS: VMX Enabled
iommu/vt-d (no such option)
CPU G6500T VT-x VT-d

BIOS.png

x2apic: Isomeone mentioned that this is a problem with the BIOS of the motherboard. I don't know if this is correct?

ESXI also can't PCI(e) passthrough
 
Last edited:

About

The Proxmox community has been around for many years and offers help and support for Proxmox VE, Proxmox Backup Server, and Proxmox Mail Gateway.
We think our community is one of the best thanks to people like you!

Get your subscription!

The Proxmox team works very hard to make sure you are running the best software and getting stable updates and security enhancements, as well as quick enterprise support. Tens of thousands of happy customers have a Proxmox subscription. Get yours easily in our online shop.

Buy now!