From: Florian Fainelli <f.fainelli@gmail.com>
To: Vladimir Oltean <vladimir.oltean@nxp.com>,
"David S . Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>
Cc: netdev@vger.kernel.org, UNGLinuxDriver@microchip.com,
Alexandre Belloni <alexandre.belloni@bootlin.com>,
Andrew Lunn <andrew@lunn.ch>,
Vivien Didelot <vivien.didelot@gmail.com>,
Horatiu Vultur <horatiu.vultur@microchip.com>,
"Allan W . Nielsen" <allan.nielsen@microchip.com>,
Claudiu Manoil <claudiu.manoil@nxp.com>,
Steen Hegelund <steen.hegelund@microchip.com>
Subject: Re: [PATCH net] net: mscc: ocelot: install MAC addresses in .ndo_set_rx_mode from process context
Date: Fri, 4 Dec 2020 09:34:54 -0800 [thread overview]
Message-ID: <ae82dc10-11af-e48a-a317-fc60cda3b993@gmail.com> (raw)
In-Reply-To: <20201204170938.1415582-1-vladimir.oltean@nxp.com>
On 12/4/2020 9:09 AM, Vladimir Oltean wrote:
> Currently ocelot_set_rx_mode calls ocelot_mact_learn directly, which has
> a very nice ocelot_mact_wait_for_completion at the end. Introduced in
> commit 639c1b2625af ("net: mscc: ocelot: Register poll timeout should be
> wall time not attempts"), this function uses readx_poll_timeout which
> triggers a lot of lockdep warnings and is also dangerous to use from
> atomic context, leading to lockups and panics.
>
> Steen Hegelund added a poll timeout of 100 ms for checking the MAC
> table, a duration which is clearly absurd to poll in atomic context.
> So we need to defer the MAC table access to process context, which we do
> via a dynamically allocated workqueue which contains all there is to
> know about the MAC table operation it has to do.
>
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Did you want to have a Fixes tag to help identify how far back this
needs to be back ported?
--
Florian
next prev parent reply other threads:[~2020-12-04 17:36 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-04 17:09 [PATCH net] net: mscc: ocelot: install MAC addresses in .ndo_set_rx_mode from process context Vladimir Oltean
2020-12-04 17:34 ` Florian Fainelli [this message]
2020-12-04 17:40 ` Vladimir Oltean
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=ae82dc10-11af-e48a-a317-fc60cda3b993@gmail.com \
--to=f.fainelli@gmail.com \
--cc=UNGLinuxDriver@microchip.com \
--cc=alexandre.belloni@bootlin.com \
--cc=allan.nielsen@microchip.com \
--cc=andrew@lunn.ch \
--cc=claudiu.manoil@nxp.com \
--cc=davem@davemloft.net \
--cc=horatiu.vultur@microchip.com \
--cc=kuba@kernel.org \
--cc=netdev@vger.kernel.org \
--cc=steen.hegelund@microchip.com \
--cc=vivien.didelot@gmail.com \
--cc=vladimir.oltean@nxp.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
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