Bug 378960

Summary: Block around cursor does not update with nvidia proprietary
Product: [Plasma] kwin Reporter: Mike C. Fletcher <mcfletch>
Component: compositingAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED NOT A BUG    
Severity: normal CC: govik
Priority: NOR    
Version First Reported In: 5.9.4   
Target Milestone: ---   
Platform: Kubuntu   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: Screenshot showing the cursor block (scrolled down while mouse was on bug-list above)

Description Mike C. Fletcher 2017-04-19 12:46:56 UTC
Created attachment 105096 [details]
Screenshot showing the cursor block (scrolled down while mouse was on bug-list above)

When rendering the screen, a block of pixels maybe 64x64 (might be 32x32 up-scaled, hard to tell with the high-res screen) around the mouse cursor does not update in response to scrolling, content changes (e.g.typing text where you click, buttons doing click animations), etc.

I can scroll quite a way and then leave the cursor sitting with an out-of-sync content background for a long period (at least 15s) without the background being updated to match the current background.

If I move the mouse after the background freezes, the background seems to be selectively updating in the direction I move, which looks like a cache-invalidation update that's taking the position and motion and only updating that part of the cursor-box that should be getting changed.

Platform: Dell XPS 9550 (Early 2016)
Graphics: GeForce GTX 960M
OS: Kubuntu 17.04 (up to date)
Comment 1 Martin Flöser 2017-04-19 14:25:15 UTC
The window manager is not responsible for rendering the mouse cursor. This is either a bug in the X server or the nvidia driver.
Comment 2 K G 2017-06-26 19:05:39 UTC
I've installed the newest nvidia drivers and I faced the same problem. 
It seams that there is problem with composite.

After switching to XRender there is no problem but. With OpenGL (2.0 and 3.1) i have problem like on the screenshot.


nvidia drivers 381.22 (the same problem with 375.x) 
kernel 4.10.0-24-generic
xserver 1:7.7+16ubuntu3

I have nvidia-prime
Grafic cards:
GM107M [GeForce GTX 960M] (rev a2)
Intel Corporation HD Graphics 530 (rev 06)