Don't acknowledge CSI detachment until volume becomes unavailable on …

…node

Longhorn 3401

Signed-off-by: Eric Weber <eric.weber@suse.com>

csi/controller_server.go

@@ -551,8 +551,12 @@ func (cs *ControllerServer) ControllerUnpublishVolume(ctx context.Context, req *
 
 	return cs.unpublishVolume(volume, nodeID, attachmentID, func() error {
 		checkVolumeUnpublished := func(vol *longhornclient.Volume) bool {
+			isRegularRWXVolume := vol.AccessMode == string(longhorn.AccessModeReadWriteMany) && !vol.Migratable
 			_, ok := vol.VolumeAttachment.Attachments[attachmentID]
-			return !ok
+			if isRegularRWXVolume {
+				return !ok
+			}
+			return !ok && !isVolumeAvailableOn(vol, nodeID)
 		}
 
 		if !cs.waitForVolumeState(volumeID, "volume unpublished", checkVolumeUnpublished, false, true) {