Dell Latitude e7450 hangs in i915 on boot with Linux 5.6-rc (Bisected)

When running Linux 5.6-rc on my Latitude e7450 (Broadwell, HD5500) (I have tried rc3 and rc4), I get a hang on every boot right when the i915 driver initializes. I attached a picture of the screen after the hang occurs. At this point the computer is hung hard and will not respond to any input other than holding down the power button to shut it off. Because of that, the logs I attached are with 5.5.7 instead.

I bisected the issue and it seems to be caused by https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/gpu/drm/i915?id=60c6a14b489baa0b591d19093ab886bec7f7fe36

I am not manually specifying any PSR settings, and neither i915.enable_psr=0 or i915.enable_psr=1 has any effect. I also tried with fastboot off and that doesn't have any effect either.

unamem.log

dmesg.log

unamer.log

added platform: BDW label

added Community label

This seems to be a dupe of #1151 (closed) which is fixed in 5.6-rc5. Closing.

closed