ConnectX3 Passthrough fail


New Member
Jun 2, 2023
Attached ConnectX3 card to my machine, Working fine on the host with bridging to the VMs


But when I try to passthrough it to the VM, I get this error

kvm: -device vfio-pci,host=0000:01:00.0,id=hostpci0,bus=pci.0,addr=0x10: vfio 0000:01:00.0: Failed to set up TRIGGER eventfd signaling for interrupt INTX-0: VFIO_DEVICE_SET_IRQS failure: Device or resource busy TASK ERROR: start failed: QEMU exited with code 1

I tried to blacklist the device, mlx4_core/mlx4_ib/mlx4_en, and it was gone from lsmod
but still same error

Any advice ?
Last edited:
I did, every part of it. including separation of IOMMU with remapping
root@pxx:~# cat /etc/modules
# /etc/modules: kernel modules to load at boot time.
# This file contains the names of kernel modules that should be loaded
# at boot time, one per line. Lines beginning with "#" are ignored.
I apologize for reviving this thread, however, I too am having the same issue. @Chura did you ever get this resolved?
I'm sorry buy I can't remember how I fixed it, I think i did not rebuild the kernel after changing the modules, but not sure.
Anyway, I did rollback eventually, since my guest OPNsense had issues with vlans on that passthrough interface which suddenly randomly hanged.
So now using bridges on Proxmox and works awesome.


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