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

winyiday

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Nov 21, 2022
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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?
 

dcsapak

Proxmox Staff Member
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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
 
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winyiday

New Member
Nov 21, 2022
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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:

dcsapak

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did you try to disable x2apic with the kernel commandline switch i mentioned? i don't see it in your logs
 

winyiday

New Member
Nov 21, 2022
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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:

dcsapak

Proxmox Staff Member
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Last edited:
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winyiday

New Member
Nov 21, 2022
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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:

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