Paint issues on latest trunk

[J. Max Mena]

This is a spinoff from #1218

I'll attach the relevant xpra info and a quick video with the paint boxes enabled. I'm honestly not sure what's up - It works fine if I roll back to r12730, but somewhere between there and r12758 it breaks. I've tried bisecting but I had no luck even after a full day of incrementally rolling through the build revisions. Somewhere around r12750 it breaks.

Once I get it broken, the repro is interesting. I don't get it with Xterms, and with Chrome it's sporadic. It's most easy to hunt down in Firefox.

• Open Firefox
• Try to highlight some text
  • It may or may not work
  • If it highlights fine then try scrolling up and down first
    • I find that's the easiest way to repro this

---

Start command:

xpra start :13 --bind-tcp=0.0.0.0:2200 --start-new-commands=yes --start-child=xterm --start-child="xterm -bg black -cr white -fg white" --start-child="xterm -bg black -cr white -fg white"

And connecting:

xpra attach tcp:ip:port

and sometimes:

XPRA_OPENGL_PAINT_BOX=1 xpra attach tcp:ip:port

---

For what it's worth, the server is a Fedora 23 hardware machine running Fedora Server. The client is also hardware, but has an Nvidia 745 GPU, the server only Intel. I also run into this issue with AND without OpenGL enabled.

[J. Max Mena]

Video of the paint issue. Note that the pauses in between are me clicking to highlight text.

[Antoine Martin]

Please include the bisection data. Even an unsuccessful bisection generates some data which may be useful in hunting down the bug. For an example of bisection data logging see ticket:557#comment:1

Also, please verify that this is a regression by testing the latest 0.17.x (and even maybe 0.14.x), bearing in mind that the bug may be present there and just harder to hit.

Does this also occur if you start the server with XPRA_VIDEO_SUBREGION=0?

Does this patch help? attachment/ticket/1218/track-nonvideo.patch

Of all the commits between r12730 and r12750:

• r12730 to r12739 are very very unlikely to cause problems as they either apply to v0.17.x branch, fix typos or build issues
• r12740 should only be relevant when using the video region API to set one
• r12741 is unlikely
• r12742 + r12743 should only affect the server xvfb startup / cleanup code, very unlikely
• r12744 could be the cause (the fix for #1218), could leave some areas not repainted
• r12745 + r12746 + r12747 + r12748 + r12749 + r12750 are all extremely unlikely to cause problems (packaging and logging changes)

[J. Max Mena]

Retested a couple times:

• Latest trunk with XPRA_VIDEO_SUBREGION=0 doesn't seem to trigger the issue
  • latest trunk being r12771

• The given patch had no effect on latest trunk

• As per your comment (comment:1), I zeroed in on r12744, and found that to be the revision where the break is introduced

• Issue does not show up in the latest 0.17.X branch.

[Antoine Martin]

See ticket:1218#comment:10

[J. Max Mena]

As per #1218, it looks like this one is fixed in r12780.

Closing, but will keep a good eye out for this one in case we see it again.

[Antoine Martin]

Milestone renamed

[migration script]

this ticket has been moved to: ​https://github.com/Xpra-org/xpra/issues/1225