netdev - Re: [PATCH net-next v2 5/6] devlink: Introduce controller number

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20200908115006.3b9ba943@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
Date:   Tue, 8 Sep 2020 11:50:06 -0700
From:   Jakub Kicinski <kuba@...nel.org>
To:     Parav Pandit <parav@...lanox.com>
Cc:     davem@...emloft.net, netdev@...r.kernel.org,
        Parav Pandit <parav@...dia.com>, Jiri Pirko <jiri@...dia.com>
Subject: Re: [PATCH net-next v2 5/6] devlink: Introduce controller number

On Tue,  8 Sep 2020 17:42:40 +0300 Parav Pandit wrote:
> A devlink port may be for a controller consist of PCI device.

Humm?

> A devlink instance holds ports of two types of controllers.
> (1) controller discovered on same system where eswitch resides
> This is the case where PCI PF/VF of a controller and devlink eswitch
> instance both are located on a single system.
> (2) controller located on external host system.
> This is the case where a controller is located in one system and its
> devlink eswitch ports are located in a different system.
> 
> When a devlink eswitch instance serves the devlink ports of both
> controllers together, PCI PF/VF numbers may overlap.
> Due to this a unique phys_port_name cannot be constructed.
> 
> For example in below such system controller-A and controller-B, each has
> PCI PF pf0 whose eswitch ports are present in controller-A.
> These results in phys_port_name as "pf0" for both.
> Similar problem exists for VFs and upcoming Sub functions.
> 
> An example view of two controller systems:
> 
>                 -----------------------------------------------------
>                 |                                                   |
>                 |           --------- ---------                     |
> -------------   |           | vf(s) | | sf(s) |                     |
> | server    |   | -------   ----/---- ---/-----  -------            |
> | pci rc    |=====| pf0 |______/________/        | pf1 |            |
> | connection|   | -------                        -------            |
> -------------   |     | controller-B (no eswitch) (controller num=1)|
>                 ------|----------------------------------------------
>                 (internal wire)
>                       |
>                 -----------------------------------------------------
>                 |  devlink eswitch ports and reps                   |
>                 |  ---------------------------------------------    |
>                 |  |ctrl-A | ctrl-B | ctrl-A | ctrl-B | ctrl-B |    |
>                 |  |pf0    | pf0    | pf0vfN | pf0vfN | pf0sfN |    |
>                 |  ---------------------------------------------    |

                                       ^^^^^^^^

ctrl-A doesn't have VFs, but sfs below.

pf1 reprs are not listed.

Perhaps it'd be clearer if controllers where not interleaved?

>                 |                                                   |
>                 |           ---------                               |
>                 |           | sf(s) |                               |
>                 | -------   ---/-----    -------                    |
>                 | | pf0 |_____/          | pf1 |                    |
>                 | -------                -------                    |
>                 |                                                   |
>                 |  local controller-A (eswitch) (controller num=0)  |
>                 -----------------------------------------------------