User: re-adding WGC brought back the teardown/recreate bug (audible disconnect/
connect on the secure<->normal switch). Cause: the secure->normal switch called
build() = vd.create() = IOCTL_REMOVE old SudoVDA monitor + IOCTL_ADD new one +
respawn the helper — the same teardown/recreate kernel stress we just eliminated
from DDA, now on the mux path.
Apply the same learning (reuse, don't tear down): the SudoVDA monitor and WGC
helper persist for the whole session; only the host-DDA leg opens (on secure)
and closes (on normal). On returning to normal, RESUME the still-alive helper
(drain its secure-dwell backlog + request a keyframe) instead of rebuilding.
The HDR-session colorspace restore (set_advanced_color(true) + helper rebuild)
is kept ONLY for bit_depth>=10 — an SDR session never changed the colorspace, so
it needs no rebuild at all. The secure switch already reuses the monitor
(open_dda on the existing target).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
enricobuehler
ca375c7ce8