| 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
| ||
|
Message-ID: <CAFSKS=NjFM6FhaUntjZ30dbU50JYnNpjrZj2KL=HAgbxk+yyuQ@mail.gmail.com>
Date: Mon, 13 Sep 2021 08:38:05 -0500
From: George McCollister <george.mccollister@...il.com>
To: Vladimir Oltean <vladimir.oltean@....com>
Cc: netdev <netdev@...r.kernel.org>,
Florian Fainelli <f.fainelli@...il.com>,
Andrew Lunn <andrew@...n.ch>,
Vivien Didelot <vivien.didelot@...il.com>,
Vladimir Oltean <olteanv@...il.com>,
"David S. Miller" <davem@...emloft.net>,
Jakub Kicinski <kuba@...nel.org>,
Kurt Kanzenbach <kurt@...utronix.de>,
Hauke Mehrtens <hauke@...ke-m.de>,
Woojung Huh <woojung.huh@...rochip.com>,
Microchip Linux Driver Support <UNGLinuxDriver@...rochip.com>,
Sean Wang <sean.wang@...iatek.com>,
Landen Chao <Landen.Chao@...iatek.com>,
DENG Qingfang <dqfext@...il.com>,
Matthias Brugger <matthias.bgg@...il.com>,
Claudiu Manoil <claudiu.manoil@....com>,
Alexandre Belloni <alexandre.belloni@...tlin.com>,
Linus Walleij <linus.walleij@...aro.org>,
Heiner Kallweit <hkallweit1@...il.com>,
Russell King <linux@...linux.org.uk>,
Oleksij Rempel <linux@...pel-privat.de>,
Michael Grzeschik <m.grzeschik@...gutronix.de>,
open list <linux-kernel@...r.kernel.org>,
"moderated list:ARM PORT" <linux-arm-kernel@...ts.infradead.org>,
linux-mediatek@...ts.infradead.org,
Lino Sanfilippo <LinoSanfilippo@....de>
Subject: Re: [RFC PATCH net 5/5] net: dsa: xrs700x: be compatible with masters
which unregister on shutdown
On Sun, Sep 12, 2021 at 7:09 AM Vladimir Oltean <vladimir.oltean@....com> wrote:
>
> Since commit 2f1e8ea726e9 ("net: dsa: link interfaces with the DSA
> master to get rid of lockdep warnings"), DSA gained a requirement which
> it did not fulfill, which is to unlink itself from the DSA master at
> shutdown time.
>
> Since the Arrow SpeedChips XRS700x driver was introduced after the bad
> commit, it has never worked with DSA masters which decide to unregister
> their net_device on shutdown, effectively hanging the reboot process.
> To fix that, we need to call dsa_switch_shutdown.
>
> These devices can be connected by I2C or by MDIO, and if I search for
> I2C or MDIO bus drivers that implement their ->shutdown by redirecting
> it to ->remove I don't see any, however this does not mean it would not
> be possible. To be compatible with that pattern, it is necessary to
> implement an "if this then not that" scheme, to avoid ->remove and
> ->shutdown from being called both for the same struct device.
>
> Fixes: ee00b24f32eb ("net: dsa: add Arrow SpeedChips XRS700x driver")
> Link: https://lore.kernel.org/netdev/20210909095324.12978-1-LinoSanfilippo@gmx.de/
> Reported-by: Lino Sanfilippo <LinoSanfilippo@....de>
> Signed-off-by: Vladimir Oltean <vladimir.oltean@....com>
> ---
> drivers/net/dsa/xrs700x/xrs700x.c | 6 ++++++
> drivers/net/dsa/xrs700x/xrs700x.h | 1 +
> drivers/net/dsa/xrs700x/xrs700x_i2c.c | 18 ++++++++++++++++++
> drivers/net/dsa/xrs700x/xrs700x_mdio.c | 18 ++++++++++++++++++
> 4 files changed, 43 insertions(+)
>
> diff --git a/drivers/net/dsa/xrs700x/xrs700x.c b/drivers/net/dsa/xrs700x/xrs700x.c
> index 130abb0f1438..469420941054 100644
> --- a/drivers/net/dsa/xrs700x/xrs700x.c
> +++ b/drivers/net/dsa/xrs700x/xrs700x.c
> @@ -822,6 +822,12 @@ void xrs700x_switch_remove(struct xrs700x *priv)
> }
> EXPORT_SYMBOL(xrs700x_switch_remove);
>
> +void xrs700x_switch_shutdown(struct xrs700x *priv)
> +{
> + dsa_switch_shutdown(priv->ds);
> +}
> +EXPORT_SYMBOL(xrs700x_switch_shutdown);
> +
> MODULE_AUTHOR("George McCollister <george.mccollister@...il.com>");
> MODULE_DESCRIPTION("Arrow SpeedChips XRS700x DSA driver");
> MODULE_LICENSE("GPL v2");
> diff --git a/drivers/net/dsa/xrs700x/xrs700x.h b/drivers/net/dsa/xrs700x/xrs700x.h
> index ff62cf61b091..4d58257471d2 100644
> --- a/drivers/net/dsa/xrs700x/xrs700x.h
> +++ b/drivers/net/dsa/xrs700x/xrs700x.h
> @@ -40,3 +40,4 @@ struct xrs700x {
> struct xrs700x *xrs700x_switch_alloc(struct device *base, void *devpriv);
> int xrs700x_switch_register(struct xrs700x *priv);
> void xrs700x_switch_remove(struct xrs700x *priv);
> +void xrs700x_switch_shutdown(struct xrs700x *priv);
> diff --git a/drivers/net/dsa/xrs700x/xrs700x_i2c.c b/drivers/net/dsa/xrs700x/xrs700x_i2c.c
> index 489d9385b4f0..6deae388a0d6 100644
> --- a/drivers/net/dsa/xrs700x/xrs700x_i2c.c
> +++ b/drivers/net/dsa/xrs700x/xrs700x_i2c.c
> @@ -109,11 +109,28 @@ static int xrs700x_i2c_remove(struct i2c_client *i2c)
> {
> struct xrs700x *priv = i2c_get_clientdata(i2c);
>
> + if (!priv)
> + return 0;
> +
> xrs700x_switch_remove(priv);
>
> + i2c_set_clientdata(i2c, NULL);
> +
> return 0;
> }
>
> +static void xrs700x_i2c_shutdown(struct i2c_client *i2c)
> +{
> + struct xrs700x *priv = i2c_get_clientdata(i2c);
> +
> + if (!priv)
> + return;
> +
> + xrs700x_switch_shutdown(priv);
> +
> + i2c_set_clientdata(i2c, NULL);
> +}
> +
> static const struct i2c_device_id xrs700x_i2c_id[] = {
> { "xrs700x-switch", 0 },
> {},
> @@ -137,6 +154,7 @@ static struct i2c_driver xrs700x_i2c_driver = {
> },
> .probe = xrs700x_i2c_probe,
> .remove = xrs700x_i2c_remove,
> + .shutdown = xrs700x_i2c_shutdown,
> .id_table = xrs700x_i2c_id,
> };
>
> diff --git a/drivers/net/dsa/xrs700x/xrs700x_mdio.c b/drivers/net/dsa/xrs700x/xrs700x_mdio.c
> index 44f58bee04a4..d01cf1073d49 100644
> --- a/drivers/net/dsa/xrs700x/xrs700x_mdio.c
> +++ b/drivers/net/dsa/xrs700x/xrs700x_mdio.c
> @@ -136,7 +136,24 @@ static void xrs700x_mdio_remove(struct mdio_device *mdiodev)
> {
> struct xrs700x *priv = dev_get_drvdata(&mdiodev->dev);
>
> + if (!priv)
> + return;
> +
> xrs700x_switch_remove(priv);
> +
> + dev_set_drvdata(&mdiodev->dev, NULL);
> +}
> +
> +static void xrs700x_mdio_shutdown(struct mdio_device *mdiodev)
> +{
> + struct xrs700x *priv = dev_get_drvdata(&mdiodev->dev);
> +
> + if (!priv)
> + return;
> +
> + xrs700x_switch_shutdown(priv);
> +
> + dev_set_drvdata(&mdiodev->dev, NULL);
> }
>
> static const struct of_device_id __maybe_unused xrs700x_mdio_dt_ids[] = {
> @@ -155,6 +172,7 @@ static struct mdio_driver xrs700x_mdio_driver = {
> },
> .probe = xrs700x_mdio_probe,
> .remove = xrs700x_mdio_remove,
> + .shutdown = xrs700x_mdio_shutdown,
> };
>
> mdio_module_driver(xrs700x_mdio_driver);
> --
> 2.25.1
>
Looks good to me.
Assuming we do Reviewed-by for RFCs:
Reviewed-by: George McCollister <george.mccollister@...il.com>
Powered by blists - more mailing lists