Created attachment 117171 [details]
xtrace part of the emacs session
When using `xrandr --setprovideroutputsource nouveau Intel` and activating a monitor through it, emacs buffers are not correctly updated when scrolling.
- use xf86-video-intel master (2c5063938cc809f624e56efd4673041fa8141e81), xorg 7.7
- open emacs with a file more than one page long
- xrandr --setprovideroutputsource nouveau Intel
- xrandr --output DP-1-2 --left-of LVDS1 --auto ([activate a monitor connected to nvidia card])
- inside emacs move inside the file (page-up/down or arrow-up/down or middle button)
- the display doesn't change, or only some line in it or only half of the buffer (vertical or horizontal)
- the buffer is scrolled normally
You need to activate a monitor connected to the nvidia card for the bug to manifest, just with setprovideroutputsource the buffer is scrolled normally. The problem appears if emacs is in the display connected to the intel card or the nvidia card. The problem also appears in the default file selector of gtk. The current master of xf86-video-intel is used in order to get the fix for #75579.
Attached is a part of the command sent by emacs to X (through xtrace) when going one line down then up with the middle mouse button. Only the last line was updated, instead of all the buffer.
Created attachment 117173 [details]
Note to self: most likely the incomplete tracking of CompositeTrapezoid by Damage