13-STABLE/drm-fbsd13-kmod: Firefox crash: Bad system call

From: FreeBSD User <freebsd_at_walstatt-de.de>
Date: Fri, 15 Oct 2021 07:52:33 UTC
After updating 13-STABLE to 13.0-STABLE #3 stable/13-n247671-70db230dcbd: Thu Oct 14
20:48:53 CEST 2021 amd64 on a Lenovo E540 notebook with Intel iGPU and also updating port
graphics/drm-fbsd13-kmod to drm-fbsd13-kmod-5.4.144.g20211013, graphics/libdrm to
libdrm-2.4.107_1,1, Firefox (firefox-93.0_1,2) crashes now with the following message:

[~] firefox
Crash Annotation GraphicsCriticalError: |[C0][GFX1-]: Receive IPC close with
reason=AbnormalShutdown (t=0.216076) Exiting due to channel error. Bad system
callgraphics/libdrm.

info on packages installed:
[~] pkg info -x drm
drm-fbsd13-kmod-5.4.144.g20211013
drm-kmod-g20190710_1
libdrm-2.4.107_1,1
linux-c7-libdrm-2.4.97

It doesn't matter whether to update the ports (including firefox) from a regular FreeBSD
ports repo or, in my case, compiling special kernel related kmod port like
drm-fbsd13-kmod manually on each kernel build. The ports package of
graphics/drm-fbsd13-kmod seems to be behind the version
of drm-fbsd13-kmod-5.4.144.g20211013 when updating from regular package host, but it
doesn't matter, the result then is the same: Bad system call on Firefox.

So FreeBSD 13-STABLE seems to be the culprit. What happened? I saw the Linux KPI changed
again, so might this trigger this? 

Kind regards,

O. Hartmann