Re: [PATCH v3] nvme-multipath: add fail_if_no_path sysfs attribute

[Keith Busch <kbusch@kernel.org>]

On Wed, Sep 23, 2026 at 11:35:24PM -0700, Krishna Iyer wrote:
> Yes, exactly. Some namespaces should keep waiting out the reconnect
> while others should stop waiting and fail their parked I/O, decided
> by a condition only userspace can see. Here that condition is a
> killed process stuck in D state on parked I/O that nothing will ever
> consume (for us a SIGKILLed VM the host must reap), and it could be
> any consumer known to be gone. Failing that namespace lets the
> process exit, while namespaces with live users behind the same
> controllers keep queueing and carry on when paths return. A
> controller wide timeout cannot separate the two, and there is no
> duration to pick up front since the trigger is userspace observing
> the event. Reconnect itself is untouched either way. So the kernel
> provides the per namespace switch and the decision stays in
> userspace.

Okay, I see. Pehaps instead of having one controller export all the
namespaces, why not configure your target to have multiple subsystems
the client makes independent connections to for each namespace?