netdev - Re: [PATCH net-next 2/3] devlink: Consider other controller while building phys_port

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: <20200827113216.7b9a3a25@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
Date:   Thu, 27 Aug 2020 11:32:16 -0700
From:   Jakub Kicinski <kuba@...nel.org>
To:     Parav Pandit <parav@...dia.com>
Cc:     Parav Pandit <parav@...lanox.com>,
        "davem@...emloft.net" <davem@...emloft.net>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "roid@...lanox.com" <roid@...lanox.com>,
        "saeedm@...lanox.com" <saeedm@...lanox.com>,
        Jiri Pirko <jiri@...dia.com>
Subject: Re: [PATCH net-next 2/3] devlink: Consider other controller while
 building phys_port_name

On Thu, 27 Aug 2020 04:31:43 +0000 Parav Pandit wrote:
> > > $ devlink port show looks like below without a controller annotation.
> > > pci/0000:00:08.0/0: type eth netdev eth5 flavour physical
> > > pci/0000:00:08.0/1: type eth netdev eth6 flavour pcipf pfnum 0
> > > pci/0000:00:08.0/2: type eth netdev eth7 flavour pcipf pfnum 0  
> > 
> > How can you have two PF 0? Aaah - by controller you mean hardware IP, not
> > whoever is controlling the switching! So the chip has multiple HW controllers,
> > each of which can have multiple PFs?
> >   
> Hardware IP is one. This IP is plugged into two PCI root complexes.
> One is eswitch PF, this PF has its own VFs/SFs.
> Other PF(s) plugged into an second PCI Root complex serving the server system.
> So you are right there are multiple PFs.

I find it strange that you have pfnum 0 everywhere but then different
controllers. For MultiHost at Netronome we've used pfnum to distinguish
between the hosts. ASIC must have some unique identifiers for each PF.

I'm not aware of any practical reason for creating PFs on one RC
without reinitializing all the others.

I can see how having multiple controllers may make things clearer, but
adding another layer of IDs while the one under it is unused (pfnum=0)
feels very unnecessary.

> Both the PFs have same PCI BDF.

BDFs are irrelevant.