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This version is superseded by v2: https://lore.kernel.org/all/20261027171055.1796482-1-peter.hunt@opengear.com/ After Loic's review, v2 only flushes dtr_work when DTR goes low and in stop(). It drops the port list, the drop flag and field, and the late bind resend. Going through the findings against v2: [High] Two reads of dtr_mdmbits in the work: gone, v2 leaves the work as it was in v10, so it reads dtr_mdmbits once. [High] Drop lost when the low state hits -EAGAIN/-ENOMEM and a raise follows within the retry delay: this can still happen in v2. The flush makes the drop go out before ->dtr_rts() returns in the normal case, but a drop that hits a full UL ring is still retried with whatever state is latest by then. The v2 commit message says so. [High] system_wq vs system_percpu_wq: agreed, that was a real problem in v1. v2 has no mod_delayed_work() calls, it only queues the work with schedule_delayed_work() as v10 does, and adds flush_delayed_work(). [Medium] Port added to the list after wwan_create_port(), and [Medium] drop lost while IP_CTRL is unbound: both are in the late bind resend, which v2 drops. Loic agreed that case, only reachable by unbinding and rebinding mhi_wwan_dtr through sysfs, can be ignored. [Low] Stale comments: the comments describe v10's latest-state work, which v2 keeps, and the drop flush has its own comment. pw-bot: cr