Hi, We created a ticket https://bugzilla.kernel.org/show_bug.cgi?id=215265 that is pretty similar to https://bugzilla.kernel.org/show_bug.cgi?id=214259. So I tried the patch on https://lkml.org/lkml/2020/6/17/751 but it doesn't fix the issue. I also tried to boot with the kernel parameter `pci=nocrs` but it changed nothing either. I attached the kernel log with thunderbolt dynamic debug on and lspci output on the ticket. Also tried to disable the intel_iommu, the DMAR failure seems to go away but thunderbolt still fails to work. Can anyone suggest what kind of information is required to help identify the cause of the problem? Thanks Chris