xsrc/57105: random Xorg crashes

[mlelstv%netbsd.org@localhost]

>Number:         57105
>Category:       xsrc
>Synopsis:       random Xorg crashes
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    xsrc-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Dec 10 16:30:01 +0000 2022
>Originator:     Michael van Elst
>Release:        NetBSD 9.99.108
>Organization:
	
>Environment:
	
	
System: NetBSD arnold 9.99.108 NetBSD 9.99.108 (EGGHED64) #64: Sat Dec 10 14:15:08 UTC 2022 mlelstv@slowpoke:/home/netbsd-current/obj.evbarm64-el/scratch/netbsd-current/src/sys/arch/evbarm/compile/EGGHED64 evbarm
Architecture: aarch64
Machine: evbarm
>Description:

After updating to latest Xorg and pixman the X server can be crashed
easily by scrolling in an xterm, e.g. by running 'dmesg' to produce
output.

This is a dumb genfb display, no drm or other magic involved.

Restoring Xorg and libpixman* from Oct 29th makes it stable again.

>How-To-Repeat:
Scroll in xterm.
>Fix:
	

>Unformatted: