Created attachment 131954 [details] kernel-log System Environment ======= ====================================== Graphic stack ====================================== ====================================== Software ====================================== kernel version : 4.12.0-rc3-drm-tip-ww22-commit-187376e+ architecture : x86_64 os version : Ubuntu 17.04 os codename : zesty kernel driver : i915 bios revision : 4.6 bios release date : 03/02/2017 hardware acceleration : enabled swap partition : enabled on (/dev/sda2) ====================================== Graphic drivers ====================================== mesa : 17.2.0-devel (git-18efb404cf modesetting : enabled modesetting compiled for : 1.19.3 X.Org Video Driver xorg-xserver : 1.19.3 libdrm : 2.4.81 vaapi (intel-driver) : Intel i965 driver for Intel(R) Haswell Mobile - 1.7.3 cairo : 1.14.8 intel-gpu-tools (tag) : intel-gpu-tools-1.18-211-g00ce341b intel-gpu-tools (commit) : 00ce341b ====================================== Hardware ====================================== platform : Haswell-Nuc motherboard id : D54250WYK form factor : Desktop cpu family : Core i5 cpu family id : 6 cpu information : Intel(R) Core(TM) i5-4250U CPU @ 1.30GHz gpu card : Intel Corporation Haswell-ULT Integrated Graphics Controller (rev 09) (prog-if 00 [VGA controller]) memory ram : 7.72 GB max memory ram : 16 GB display resolution : 4864x2160 cpu thread : 4 cpu core : 2 cpu model : 69 cpu stepping : 1 socket : Socket LGA1150 signature : Type 0, Family 6, Model 69, Stepping 1 hard drive : 223GiB (240GB) current cd clock frequency : 450000 kHz maximum cd clock frequency : 450000 kHz displays connected : DP-2 DP-6 ====================================== Firmware ====================================== ====================================== kernel parameters ====================================== quiet splash fastboot drm.debug=0xe Regression? ======= Unknown Bug detailed description ===== == The display renders incorrectly, a segment of it displays scrolled as if it would render the first half in the second half or the bottom two quarters of the screen instead of the first two quarters, or sometimes the screen gets rendered 3 or 4 times though at a lower resolution scale, multiple times inside the display. Reproduce Steps ============== Use xrandr to list the resolution and frequencies and manually change resolutions from highest to lowest (including frequency changes), the error will start happening at resolutions lower than 1440x900. Expected Result ============= Resolution and frequency should change correctly. Actual Result =========== Screen corruption. Analysis & Root Cause =================== Unknown, probably a misaligned buffer due to some exception.
Hello Victor, if possible could you please add also the dmesg log? Thank you.
The Kernel log has been removed and rewritten by the OS as if it was output directly from the dmesg command.
Created attachment 131956 [details] dmesg log A more specific dmesg log is attached. It includes the output given right up from the testing that was done in order to reproduce the bug.
Adding tag into "Whiteboard" field - ReadyForDev *Status is correct *Platform is included *Feature is included *Priority and Severity correctly set *Logs included
Analyzing the hardware specifications of "DisplayPort to Dual DisplayPort Graphics Splitter DPD2001 SUNIX" MST. We have identified that DP 1.2 does not support enough bandwidth over a single link to drive two 4k monitors, and this should not be a mistake anymore. Adding DataSheet URL http://www.sunix.com/en/download.php?pid=1720&file=datasheet&file_link=download/datasheet/2014/20141119170512_DPD2001-Datasheet-V12.pdf
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