Re: [PATCH net-next v10 1/2] net: wwan: core: propagate modem control signals to port drivers

[Peter Hunt]

Thanks for the review.

[Medium] termios/TIOCM ioctls waiting behind a blocking write: this is
a trade-off discussed on v8, where Loic chose a single ops_lock for now,
with finer-grained locking possibly later. In v10 the lock is only held
around the termios/TIOCM state, never across a user copy, the wait is
interruptible, and ioctls that don't touch that state don't take it.

No in-tree driver implements both ->tx_blocking and ->dtr_rts, so the
circular wait you describe can't happen today. If the maintainers would
rather keep the termios/TIOCM state under a lock the TX path doesn't
hold, I'm happy to do that as a follow-up.