Severe tearing and display corrupting when using SNA

Submitted by nvaert1986@hotmail.com

Assigned to Chris Wilson @ickle

Link to original bug (#110245)

Description

Dear sir/miss,

I'm using a Lenovo ThinkPad P52 (Intel Core i7-8750H) with the latest 1.22 UEFI firmware and have severe screen tearing and display corruption when using the xf86-video-intel driver. When I'm using the latest stable driver version and the situation is sometimes unworkable, because the screen simply goes blank and can't even revert back to the TTY after a while (I've got no display at all). When I'm using the latest GIT version the driver is stable, but I've got severe tearing and artifacts (square cubes in red / greenish in particular). I've tried both DRI 2 and DRI 3, but that doesn't make a difference. The situation is stable when using the modesetting driver, but then I can't use my external displays, as it's hard-wired to the NVIDIA chip. The same goes for uxa driver, it doesn't allow me to use intel-virtual-output, so sna is the only option for me. (I'm making use of bumblebee / bbswitch and intel-virtual-output) This can especially be observed when browsing websites.

I'm running Gentoo Linux with kernel 4.19.27 with xorg-server-1.20.3. If there's anything additional you need, please let me know