From: Andrew Lunn <andrew@lunn•ch>
To: Robert Hancock <hancock@sedsystems•ca>
Cc: netdev@vger•kernel.org, arkadis@mellanox•com
Subject: Re: Errors enabling bridge with KSZ9897 DSA switch driver
Date: Sun, 23 Dec 2018 21:57:34 +0100 [thread overview]
Message-ID: <20181223205734.GG2791@lunn.ch> (raw)
In-Reply-To: <b73220ea-3807-7571-4e04-a392a3a5ba3e@sedsystems.ca>
On Sun, Dec 23, 2018 at 01:29:42PM -0600, Robert Hancock wrote:
> On 2018-12-23 5:23 a.m., Andrew Lunn wrote:
> >On Sat, Dec 22, 2018 at 08:29:08PM -0600, Robert Hancock wrote:
> >>I have a device using a KSZ9897 switch
> >>(CONFIG_MICROCHIP_KSZ_SPI_DRIVER=y) using a 4.19.9 kernel, where I am
> >>trying to enable a bridge on some of the ports using systemd-networkd.
> >
> >Hi Robert
> >
> >I don't think many of use use such a setup, so we probably have not
> >noticed this.
> >
> >>However, it seems to be getting an error when it tries to configure the
> >>ports to be part of the bridge. systemd-networkd complains with:
> >>
> >>lan1: Set link
> >>lan1: Could not join netdev: Operation not supported
> >>lan1: Failed
> >>
> >>and the kernel complains:
> >>
> >>lan: bridge flag offload is not supported 4(lan1)
> >>
> >>That message is coming from br_switchdev_set_port_flag in
> >>net/bridge/br_switchdev.c. Adding some more output to that statement
> >>tells me:
> >>
> >>lan: bridge flag offload is not supported, flags 18656 mask 64 support
> >>0, 4(lan1)
> >>
> >>which appears to mean something is trying to enable BR_BCAST_FLOOD,
> >>BR_MCAST_FLOOD, BR_PROMISC, BR_FLOOD, BR_LEARNING on the port, but it is
> >>failing to enable BR_FLOOD because brport_flags_support is 0. I am just
> >>using the default bridge settings in systemd-networkd, so that is
> >>nothing that I am specifying explicitly.
> >
> >I think this is a systemd problem. It should first query what flags
> >are supported. See
> >
> >dc0ecabd6231 ("net: switchdev: Add support for querying supported bridge flags by hardware")
> >
> >And then only try to turn on flags which are supported. If it tries
> >to turn on flags which are not supported, an error is the correct
> >thing to do.
>
> I may be missing some context about how the switchdev/DSA code works, but
> are those flags actually unsupported, or just unsupported in hardware
> offload? Userspace doesn't know or care about the hardware offload
> capability of the switch, it's just trying to set standard flags on the
> bridge.
Hi Robert
We really need Arkadi Sharshevsky to comment on this.
Andrew
next prev parent reply other threads:[~2018-12-23 20:57 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-12-23 2:29 Errors enabling bridge with KSZ9897 DSA switch driver Robert Hancock
2018-12-23 4:47 ` Robert Hancock
2018-12-23 11:23 ` Andrew Lunn
2018-12-23 19:29 ` Robert Hancock
2018-12-23 20:57 ` Andrew Lunn [this message]
2018-12-27 23:32 ` Robert Hancock
2018-12-28 8:48 ` Andrew Lunn
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20181223205734.GG2791@lunn.ch \
--to=andrew@lunn$(echo .)ch \
--cc=arkadis@mellanox$(echo .)com \
--cc=hancock@sedsystems$(echo .)ca \
--cc=netdev@vger$(echo .)kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox