During an HSM archive or restore, the progress is reported by the copytool, in userspace. That value may be bogus. For
instance, this will crash the MDS in interval_set():

he.offset = -1;
he.length = 10;
rc = llapi_hsm_action_progress(hcp, &he, length, 0);

So check that userspace is giving a sane progress extent value.