vgsp-sema: resync a CE channel past residual USERD state on counter reset (ISSUE-0002)

r48: the layout USERD of the second session's rank0 was accepted with the
previous session's residual PUT=134; the pump consumed 34 stale slots, then
the guest's fresh counter reset PUT to 1 and the pump wrapped: last_get never
matched the guest's sequence and the live first push was not processed. The
client was later seen pushing 216-byte no-release entries with crel frozen.
A fresh channel's first push always publishes PUT<=1 and the client waits for
its release before a second push, so a PUT>=2 at discovery is residual: seed
last_get past it and resync to slot 0 when the guest's own counter reset
drops PUT below put_prev. Clear the wait state once entries are consumed
without a reset so later genuine wraps keep the normal wrap path.

0 files changed, 0 insertions, 0 deletions