Created attachment 1132156 [details] dmesg log Description of problem: I have a laptop a base, with a separate screen plug on the dock's displayport output. With using one screen has an extension of the other, after a few minutes, the screen turn black, or with glitches. Using same image on both screen works fine. Using only one screen or the other works fine. Version-Release number of selected component (if applicable): Linux jportable.localdomain 4.4.2-301.fc23.x86_64 #1 SMP Tue Feb 23 19:00:38 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux How reproducible: always Steps to Reproduce: 1. use double screen with display port 2. wait
Last dmesg line are : [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe B FIFO underrun [drm:intel_pch_fifo_underrun_irq_handler [i915]] *ERROR* PCH transcoder B FIFO underrun
Created attachment 1132157 [details] lspci -vv
after using more my laptop and having only external screen use, the same problem occurs, so I assume it is not double screen related.
I've made a video : https://holcroft.fr/oc/index.php/s/A1XitNIDp6jl6wi Note : using gnome shell screen recorder don't show any bug. I assume it may be related to : A test engineer may have spotted it, but I assume nobody saw his message : http://www.gossamer-threads.com/lists/linux/kernel/2105696 This post : https://bbs.archlinux.org/viewtopic.php?id=207412 brang me to this one that really look similar : https://bbs.archlinux.org/viewtopic.php?id=209026 I assume it's not a display-port issue but i915 regression in 4.4 I've reach my skill limit, may someone help to solve it ?
Absolutely same problem with thinkpad x201 ultrabay and ASUS displayport display.
this bug looks like fixed # uname -a Linux jportable.localdomain 4.4.4-301.fc23.x86_64 #1 SMP Fri Mar 4 17:42:42 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
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