[PATCH] nvme: fix racy access to FDP placement id array

[Christoph Hellwig]

> +	if (ctrl->ctratt & NVME_CTRL_ATTR_FDPS) {
> +		ns->head = head;
> +		ret = nvme_query_fdp_info(ns, info);
> +		if (ret < 0)
> +			goto out_clear_ns_head;
> +	}

The conditional assignment of ns->head here is weird.  Just pass it
explicitly to nvme_query_fdp_info so that you don't have this issue.

Otherwise the patch looks good.