Aw: Re: [PATCH 0/3] Fix for KSZ DSA switch shutdown

From: Lino Sanfilippo
Date: Mon Sep 13 2021 - 06:32:36 EST


Hi,

> Gesendet: Sonntag, 12. September 2021 um 22:29 Uhr
> Von: "Vladimir Oltean" <olteanv@xxxxxxxxx>
> An: "Lino Sanfilippo" <LinoSanfilippo@xxxxxx>
> Cc: "Andrew Lunn" <andrew@xxxxxxx>, "Florian Fainelli" <f.fainelli@xxxxxxxxx>, "Saravana Kannan" <saravanak@xxxxxxxxxx>, "Rafael J. Wysocki" <rafael@xxxxxxxxxx>, p.rosenberger@xxxxxxxxxx, woojung.huh@xxxxxxxxxxxxx, UNGLinuxDriver@xxxxxxxxxxxxx, vivien.didelot@xxxxxxxxx, davem@xxxxxxxxxxxxx, kuba@xxxxxxxxxx, netdev@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx
> Betreff: Re: [PATCH 0/3] Fix for KSZ DSA switch shutdown
>
> On Sun, Sep 12, 2021 at 10:19:24PM +0200, Lino Sanfilippo wrote:
> >
> > Hi,
> >
> > On 10.09.21 at 16:58, Vladimir Oltean wrote:
> > > On Fri, Sep 10, 2021 at 01:51:56PM +0200, Andrew Lunn wrote:
> > >>> It does not really scale but we also don't have that many DSA masters to
> > >>> support, I believe I can name them all: bcmgenet, stmmac, bcmsysport, enetc,
> > >>> mv643xx_eth, cpsw, macb.
> > >>
> > >> fec, mvneta, mvpp2, i210/igb.
> > >
> > > I can probably double that list only with Freescale/NXP Ethernet
> > > drivers, some of which are not even submitted to mainline. To name some
> > > mainline drivers: gianfar, dpaa-eth, dpaa2-eth, dpaa2-switch, ucc_geth.
> > > Also consider that DSA/switchdev drivers can also be DSA masters of
> > > their own, we have boards doing that too.
> > >
> > > Anyway, I've decided to at least try and accept the fact that DSA
> > > masters will unregister their net_device on shutdown, and attempt to do
> > > something sane for all DSA switches in that case.
> > >
> > > Attached are two patches (they are fairly big so I won't paste them
> > > inline, and I would like initial feedback before posting them to the
> > > list).
> > >
> > > As mentioned in those patches, the shutdown ordering guarantee is still
> > > very important, I still have no clue what goes on there, what we need to
> > > do, etc.
> > >
> >
> > I tested these patches with my 5.10 kernel (based on Gregs 5.10.27 stable
> > kernel) and while I do not see the message "unregister_netdevice: waiting
> > for eth0 to become free. Usage count = 2." any more the shutdown/reboot hangs, too.
> > After a few attempts without any error messages on the console I was able to get a
> > stack trace. Something still seems to go wrong in bcm2835_spi_shutdown() (see attachment).
> > I have not had the time yet to investigate this further (or to test the patches
> > with a newer kernel).
>
> Could you post the full kernel output? The picture you've posted is
> truncated and only shows a WARN_ON in rpi_firmware_transaction and is
> probably a symptom and not the issue (which is above and not shown).
>

Unfortunately I dont see anything in the kernel log. The console output is all I get,
thats why I made the photo.

Regards,
Lino