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Date: Wed, 24 Sep 2025 17:35:51 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Yangfl <mmyangfl@gmail.com>
Cc: netdev@vger.kernel.org, Andrew Lunn <andrew@lunn.ch>, Vladimir Oltean
 <olteanv@gmail.com>, "David S. Miller" <davem@davemloft.net>, Eric Dumazet
 <edumazet@google.com>, Paolo Abeni <pabeni@redhat.com>, Rob Herring
 <robh@kernel.org>, Krzysztof Kozlowski <krzk+dt@kernel.org>, Conor Dooley
 <conor+dt@kernel.org>, Heiner Kallweit <hkallweit1@gmail.com>, Russell King
 <linux@armlinux.org.uk>, Simon Horman <horms@kernel.org>,
 devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next v11 5/5] net: dsa: yt921x: Add support for
 Motorcomm YT921x
Message-ID: <20250924173551.2e09b168@kernel.org>
In-Reply-To: <CAAXyoMNBHgG-DFv16ua-T__iBXg=chFQ6TNoXdZvk4VP2aYESA@mail.gmail.com>
References: <20250922131148.1917856-1-mmyangfl@gmail.com>
	<20250922131148.1917856-6-mmyangfl@gmail.com>
	<20250923174737.4759aaf4@kernel.org>
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On Wed, 24 Sep 2025 20:33:57 +0800 Yangfl wrote:
> On Wed, Sep 24, 2025 at 8:47=E2=80=AFAM Jakub Kicinski <kuba@kernel.org> =
wrote:
> > > +             cancel_delayed_work_sync(&pp->mib_read);
> > > +     }
> > > +
> > > +     dsa_unregister_switch(&priv->ds); =20
> >
> > The work canceling looks racy, the port can come up in between
> > cancel_work and dsa_unregister ? disable_delayed_work.. will likely
> > do the job. =20
>=20
> Are you sure about this? There are many others who use
> cancel_delayed_work_sync in their teardown methods (for example
> ar9331_sw_remove). If that is true, they should be fixed too.

Not at all! I'll gladly accept an explanation of why the code is
correct. "Someone else is doing it too" is not an explanation.