sway-1.2_1 crashes

[John Kennedy]

I've finally made some progress using wayland (vs X, via sway) and I'm seeing
some crashes.  I'm compiling packages myself, so should have the latest.  A
sampling of port versions based on what I typically see people ask about:

	sway-1.2_1
	wayland-1.16.0_1
	xwayland-1.19.1_11,1
	xinput-1.6.3
	mesa-dri-18.3.2_7 (should be compiled with llvm80-8.0.1_3)
	mesa-libs-18.3.2_2 (should be compiled with llvm80-8.0.1_3)
	drm-kmod-g20190710 -> drm-fbsd12.0-kmod-4.16.g20190814

I haven't been running it that long, days really, so don't have a happy story
to start with other than X is solid on that system.  I'm currently kludging
/dev/input/* permissions (+rw to video group) to get it to start up.

	2019-10-07 08:56:30 - [main.c:300] Found config * for output DP-2 (Dell Inc. DELL P2414H 524N34643LDL)
	2019-10-07 08:57:59 - [xwayland/xwm.c:1267] xcb error: op ChangeProperty (no minor), code Window (no extension), sequence 521, value 8388630
	2019-10-07 09:00:06 - [backend/drm/atomic.c:38] Atomic test failed: Invalid argument
	2019-10-07 09:00:17 - [xwayland/xwm.c:1267] xcb error: op ChangeProperty (no minor), code Window (no extension), sequence 1317, value 23068685
	2019-10-07 09:02:01 - [xwayland/xwm.c:1267] xcb error: op ChangeProperty (no minor), code Window (no extension), sequence 1400, value 23068685
	2019-10-07 09:03:39 - [xwayland/xwm.c:1267] xcb error: op ChangeProperty (no minor), code Window (no extension), sequence 1473, value 23068685
	2019-10-07 09:04:44 - [xwayland/xwm.c:1267] xcb error: op ChangeProperty (no minor), code Window (no extension), sequence 1532, value 23068685
	2019-10-07 09:06:59 - [sway/desktop/transaction.c:464] Unable to create transaction timer (some imperfect frames might be rendered): Resource temporarily unavailable
	2019-10-07 09:08:13 - [xwayland/xwm.c:1267] xcb error: op ChangeProperty (no minor), code Window (no extension), sequence 1938, value 27262983
	2019-10-07 09:08:18 - [sway/desktop/transaction.c:464] Unable to create transaction timer (some imperfect frames might be rendered): Resource temporarily unavailable
	...  **LOTS** more of those ...
	2019-10-07 09:12:11 - [sway/desktop/transaction.c:464] Unable to create transaction timer (some imperfect frames might be rendered): Resource temporarily unavailable
	2019-10-07 09:13:09 - [xwayland/xwm.c:179] Could not add timer to event loop
	(EE) 
	Fatal server error:
	(EE) failed to read Wayland events: Broken pipe
	(EE) 
	Segmentation fault
	urxvt: X connection to ':0' broken, unable to recover, exiting.

When it fails, it drops back to text mode.  It seems to have a combination of
"load: 0.16 is not a controlling termal" (load # seems to vary) and what I
guess is some binary junk written to stdout.  They keyboard ends up very
wedged (can't even gets caps-lock to toggle lights, mouse doesn't move the
pointer).  Powering off via button gest a graceful shutdown and the output
that I captured, above.

Currently FreeBSD 12.1-BETA3 #124 r353272.

Some drm output from /var/log/messages:

	Oct  7 09:16:33 bsd kernel: [drm] Unable to create a private tmpfs mount, hugepage support will be disabled(-19).
	Oct  7 09:16:33 bsd kernel: Failed to add WC MTRR for [0xe0000000-0xefffffff]: -22; performance may suffer
	Oct  7 09:16:33 bsd kernel: [drm] Got stolen memory base 0xdd200000, size 0x2000000
	Oct  7 09:16:33 bsd kernel: [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
	Oct  7 09:16:33 bsd kernel: [drm] Driver supports precise vblank timestamp query.
	Oct  7 09:16:33 bsd kernel: [drm] Connector VGA-1: get mode from tunables:
	Oct  7 09:16:33 bsd kernel: [drm]   - kern.vt.fb.modes.VGA-1
	Oct  7 09:16:33 bsd kernel: [drm]   - kern.vt.fb.default_mode
	Oct  7 09:16:33 bsd kernel: [drm] Connector DP-1: get mode from tunables:
	Oct  7 09:16:33 bsd kernel: [drm]   - kern.vt.fb.modes.DP-1
	Oct  7 09:16:33 bsd kernel: [drm]   - kern.vt.fb.default_mode
	Oct  7 09:16:33 bsd kernel: [drm] Connector HDMI-A-1: get mode from tunables:
	Oct  7 09:16:33 bsd kernel: [drm]   - kern.vt.fb.modes.HDMI-A-1
	Oct  7 09:16:33 bsd kernel: [drm]   - kern.vt.fb.default_mode
	Oct  7 09:16:33 bsd kernel: [drm] Connector DP-2: get mode from tunables:
	Oct  7 09:16:33 bsd kernel: [drm]   - kern.vt.fb.modes.DP-2
	Oct  7 09:16:33 bsd kernel: [drm]   - kern.vt.fb.default_mode
	Oct  7 09:16:33 bsd kernel: [drm] Connector HDMI-A-2: get mode from tunables:
	Oct  7 09:16:33 bsd kernel: [drm]   - kern.vt.fb.modes.HDMI-A-2
	Oct  7 09:16:33 bsd kernel: [drm]   - kern.vt.fb.default_mode
	Oct  7 09:16:33 bsd kernel: [drm] Initialized i915 1.6.0 20171222 for drmn0 on minor 0