FS#65362 - CONFIG_INTEL_IOMMU_DEFAULT_ON=yes on 5.5.1.arch1-1 causes random system freezes (thinkpad x201)

Attached to Project: Arch Linux
Opened by Imtz (glucosonte) - Monday, 03 February 2020, 22:23 GMT
Last edited by Doug Newgard (Scimmia) - Wednesday, 05 February 2020, 13:35 GMT
Task Type Bug Report
Category Packages: Core
Status Closed
Assigned To No-one
Architecture x86_64
Severity Medium
Priority Normal
Reported Version
Due in Version Undecided
Due Date Undecided
Percent Complete 100%
Votes 3
Private No

Details

The change to CONFIG_INTEL_IOMMU_DEFAULT_ON=yes on 5.5.1.arch1-1 causes random system freezes on my Thinkpad x201. I have not been able to reproduce the issue consistently.

I can see multiple lines like the following:
---
Feb 03 22:43:13 sriracha kernel: [drm:i915_gem_gtt_finish_pages [i915]] *ERROR* Failed to wait for idle; VT'd may hang.
---

The messages started once I updated the package from linux-5.4.15.arch1-1-x86_64 to linux-5.5.1.arch1-1

Rolling back to the previous version 5.4.15 stops the issue.

This might be related to an upstream bug https://bugzilla.kernel.org/show_bug.cgi?id=197029 and it seems triggered by enabling CONFIG_INTEL_IOMMU_DEFAULT_ON=yes
This task depends upon

Closed by  Doug Newgard (Scimmia)
Wednesday, 05 February 2020, 13:35 GMT
Reason for closing:  Fixed
Additional comments about closing:  linux 5.5.1.arch2-1
Comment by Imtz (glucosonte) - Monday, 03 February 2020, 22:41 GMT
Adding intel_iommu=off or intel_iommu=igfx_off seem to solve the issue (at least I see no more messages like:
[drm:i915_gem_gtt_finish_pages [i915]] *ERROR* Failed to wait for idle; VT'd may hang.

Comment by Federico Quagliata (quaqo) - Tuesday, 04 February 2020, 16:04 GMT
Same here. I just upgraded and couldn't go past some steps of boot process twice. I finally managed to boot and found the same error referring to IOMMU. I know disabled it thru intel_iommu=off.

Loading...