When kwin_wayland tries to start XWayland, XWayland hangs with endless inet6-related errors

Submitted by kyl..@..ab.com

Assigned to Wayland bug list

Link to original bug (#106573)

Description

This happens when I start KWin from the VT using startplasmawayland, or starting a nested kwin_wayland using the --xwayland option.

I get this error repeated endlessly:

_XSERVTransSocketOpenCOTSServer: Unable to open socket for inet6 _XSERVTransOpen: transport open failed for inet6/valmar-desktop:15579 _XSERVTransMakeAllCOTSServerListeners: failed to open listener for inet6

I run a custom Arch kernel with IPv6 disabled, because it has caused mysterious DNS resolution slowdown for me in the past, but this didn't cause XWayland any issue.

XWayland should fallback to inet4 if an inet6 socket cannot be opened.