Storage removal is now robust to all three ways a volume can leave, and the docs
say so. storage-architecture.md and storage-design-rationale.md move medium_changed
from "planned to be consumed" to consumed, and record the third trigger:
- the DEVICE leaving the tree (a pulled stick) — presence polling
- the MEDIUM leaving while its device stays (a reader) — the volume manager
now consumes the pushed medium_changed event
- the storage DRIVER crashing while its device stays — a channel-liveness
geometry() probe reaps the volume and rebuilds it on the restarted driver's
fresh channel; presence polling alone cannot see this (the V4 open edge)
The re-adopt-and-remount path is QEMU-proven by the driver-crash rebuild; a
physical unplug/replug is bench-verified (QEMU cannot re-present a usb-storage
device_add). The transport-native eject signal (SCSI UNIT ATTENTION, AHCI
PxSSTS, NVMe namespace-change AER) in place of the TEST UNIT READY poll stays
the documented future refinement.
Daniel Samson
4dfb5012c0