Subject: Re: [PATCH 11/11] iscsi: force destroy sesions when a network namespace exits

From: Chris Leech <[email-masked]>
Date: Tue, 11 Apr 2023 11:19:45 -0700

On Tue, Apr 11, 2023 at 08:21:22AM +0200, Hannes Reinecke wrote:
> On 4/10/23 21:10, Chris Leech wrote:
> > The namespace is gone, so there is no userspace to clean up.
> > Force close all the sessions.
> > 
> > This should be enough for software transports, there's no implementation
> > of migrating physical iSCSI hosts between network namespaces currently.
> > 
> Ah, you shouldn't have mentioned that.
> (Not quite sure how being namespace-aware relates to migration, though.)
> We should be checking/modifying the iSCSI offload drivers, too.
> But maybe with a later patch.

I shouldn't have left that opening ;-)

The idea with this design is to keep everything rooted on the
iscsi_host, and for physical HBAs those stay assigned to init_net.
With this patch set, offload drivers remain unusable in a net namespace
other than init_net. They simply are not visible.

By migration, I was implying the possibilty of assigment of an HBA
iscsi_host into a namespace like you can do with a network interface.
Such an iscsi_host would then need to be migrated back to init_net on
namespace exit.

I don't think it works to try and share an iscsi_host across namespaces,
and manage different sessions. The iSCSI HBAs have a limited number of
network configurations, exposed as iscsi_iface objects, and I don't want
to go down the road of figuring out how to share those.

- Chris