working system and suddenly dmar error with iommu=on

bforpc

Renowned Member
Nov 26, 2013
151
5
83
Hamburg
Hi folks,

my system is running 12 month without problems with the kernel boot parameter intel_iommu=on.
No changes at hardware. Everything was fine - pci passtrough is working.
But now i get millions of dmar errors and proxmox is not booting. Only without the above kernel parameter. But then, the pci-passtrough is not working.
So my first thought was: the mainboard.
But it isn't. I have change it to an other modell with same chipset (Intel Z87) - but the error is still there... so what now ?
Is this a proxmox/Linux error and i should reinstall proxmox host ?

jan