Re: [PATCH 5.12 081/363] net: bridge: propagate error code and extack from br_mc_disabled_update

[Greg Kroah-Hartman]

On Tue, May 18, 2021 at 12:24:57PM +0000, Rudi Heitbaum wrote:
> On Mon, May 17, 2021 at 03:59:07PM +0200, Greg Kroah-Hartman wrote:
> > From: Florian Fainelli <f.fainelli@xxxxxxxxx>
> > 
> > [ Upstream commit ae1ea84b33dab45c7b6c1754231ebda5959b504c ]
> > 
> > Some Ethernet switches might only be able to support disabling multicast
> > snooping globally, which is an issue for example when several bridges
> > span the same physical device and request contradictory settings.
> > 
> > Propagate the return value of br_mc_disabled_update() such that this
> > limitation is transmitted correctly to user-space.
> > 
> > Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
> > Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
> > Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
> > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> > ---
> >  net/bridge/br_multicast.c | 28 +++++++++++++++++++++-------
> >  net/bridge/br_netlink.c   |  4 +++-
> >  net/bridge/br_private.h   |  3 ++-
> >  net/bridge/br_sysfs_br.c  |  8 +-------
> >  4 files changed, 27 insertions(+), 16 deletions(-)
> 
> This patch results in docker failing to start, and a regression between
> 5.12.4 and 5.12.5-rc1
> 
> A working dmesg output is like:
> 
> [   11.545255] device eth0 entered promiscuous mode
> [   11.693848] process 'docker/tmp/qemu-check643160757/check' started with executable stack
> [   17.233059] br-92020c7e3aea: port 1(veth17a0552) entered blocking state
> [   17.233065] br-92020c7e3aea: port 1(veth17a0552) entered disabled state
> [   17.233098] device veth17a0552 entered promiscuous mode
> [   17.292839] docker0: port 2(veth9d227f5) entered blocking state
> [   17.292848] docker0: port 2(veth9d227f5) entered disabled state
> [   17.292946] device veth9d227f5 entered promiscuous mode
> [   17.293070] docker0: port 2(veth9d227f5) entered blocking state
> [   17.293075] docker0: port 2(veth9d227f5) entered forwarding state
> 
> with this patch "device veth17a0552 entered promiscuous mode" never
> shows up.
> 
> the docker error itself is:
> 
> docker: Error response from daemon: failed to create endpoint
> sleepy_dijkstra on network bridge: adding interface veth8cbd8f9 to
> bridge docker0 failed: operation not supported.

Ick.

Does 5.13-rc1 also show this same problem?

And thanks for testing!

greg k-h