Re: [dpdk-dev] [PATCH 2/2] app/testpmd: fix hot-unplug detaching

[Thomas Monjalon <thomas@monjalon.net>]

16/02/2020 09:09, Matan Azrad:
> Hi Thomas
> 
> Thanks for the patches, I Saw it just now.
>  please see small comment below:
> 
>  From: Thomas Monjalon
> > There is a possible race condition in the hotplug path in rmv_port_callback().
> > If a port is created between
> > close_port(port_id) and detach_port_device(port_id), then the port_id will
> > have been reallocated to a different device which will be wrongly detached.
> > 
> > Since a check was added in detach_port_device() for manual detach case,
> > the hotplug path was even more broken.
> > It became impossible to run because the new check prevented to run
> > detach_port_device() after the port is closed.
> > 
> > The solution for both issues is to not rely on the port_id for detaching the
> > rte_device.
> > The function detach_port_device() is split to allow calling
> > detach_device() directly with the rte_device pointer, saved before closing
> > the port.
> > 
> > Fixes: 43d0e304980a ("app/testpmd: fix invalid port detaching")
> 
> If you fix the race, Don't you think you need to add fixes line for the patch which created the race?

Yes, you're right, I forgot it.
It is too late now unfortunately, but we may request to backport it
properly in 18.11 as well.

Please Kevin, add this tag so it will be part of 18.11:

Fixes: cbb4c648c5df ("ethdev: use device handle to detach")

> > Cc: stable@dpdk.org