To everyone testing on Intel chipsets, make sure to also test with either LibreOffice or PyCharm/JetBrains IDE and manipulate (resize/move/type in the UI) to attempt to trigger the i915 VMA/list corruption bugs.
@jforbes, I hit it immediately trying your kernel build with 5.5.2 from Koji installed manually. I was one of the first reporters too: https://gitlab.freedesktop.org/drm/intel/issues/1179
Dell Precision 5540 (Coffeelake)
5.5.x are missing critical patches in drm/i915 which render Intel systems unusable (hanging X) with all 5.5 kernels. The patches into 5.5.x are pending but are not there yet.
https://gitlab.freedesktop.org/drm/intel/issues/1201 https://www.phoronix.com/scan.php?page=news_item&px=Linux-5.5-Intel-Missed-Graphics
This build fixed Intel AX200 iwlwifi firmware crashing bug: https://bugzilla.redhat.com/show_bug.cgi?id=1738361
Intel AX200 WiFi 6 does not work with 5.2.x kernels due to firmware version mismatch.
@jforbes FYI:
https://gitlab.manjaro.org/packages/core/linux55/blob/master/0014-drm-i915-introduce-a-vma.kref.patch https://gitlab.manjaro.org/packages/core/linux55/blob/master/0008-drm-i915-serialise-i915_active_acquire()with__active_retire().patch