Re: [PATCH v2] nvme-tcp: Check if request has started before processing it

From: Daniel Wagner
Date: Thu Mar 11 2021 - 04:44:21 EST


Hi Sagi,

On Fri, Mar 05, 2021 at 11:57:30AM -0800, Sagi Grimberg wrote:
> Daniel, again, there is nothing specific about this to nvme-tcp,
> this is a safeguard against a funky controller (or a different
> bug that is hidden by this).

As far I can tell, the main difference between nvme-tcp and FC/NVMe,
nvme-tcp has not a FW or a big driver which filter out some noise from a
misbehaving controller. I haven't really checked the other transports
but I wouldn't surprised they share the same properties as FC/NVMe.

> The same can happen in any other transport so I would suggest that if
> this is a safeguard we want to put in place, we should make it a
> generic one.
>
> i.e. nvme_tag_to_rq() that _all_ transports call consistently.

Okay, I'll review all the relevant code and see what could made more
generic and consistent.

Though I think nvme-tcp plays in a different league as it is exposed to
normal networking traffic and this is a very hostile environment.

Thanks,
Daniel