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Date: Tue, 25 Mar 2025 10:04:12 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Cosmin Ratiu <cratiu@nvidia.com>
Cc: "davem@davemloft.net" <davem@davemloft.net>, "sdf@fomichev.me"
 <sdf@fomichev.me>, "horms@kernel.org" <horms@kernel.org>,
 "edumazet@google.com" <edumazet@google.com>, "netdev@vger.kernel.org"
 <netdev@vger.kernel.org>, "andrew+netdev@lunn.ch" <andrew+netdev@lunn.ch>,
 "pabeni@redhat.com" <pabeni@redhat.com>
Subject: Re: [PATCH net-next v2 08/11] net: make NETDEV_UNREGISTER and
 instance lock more consistent
Message-ID: <20250325100412.73b49ded@kernel.org>
In-Reply-To: <0be167ba394a9485c78c67d187ec546131a5cbe1.camel@nvidia.com>
References: <20250324224537.248800-1-kuba@kernel.org>
	<20250324224537.248800-9-kuba@kernel.org>
	<0be167ba394a9485c78c67d187ec546131a5cbe1.camel@nvidia.com>
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On Tue, 25 Mar 2025 12:17:15 +0000 Cosmin Ratiu wrote:
> > +	netdev_lock_ops(dev);
> > =C2=A0	call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
> > +	netdev_unlock_ops(dev);
> > =C2=A0} =20
>=20
> This introduces a potential deadlock when changing a device namespace:
> do_setlink already locks the instance lock and
> call_netdevice_unregister_notifiers will then deadlock.

Thanks for catching, the notifiers need a closer look.
Let me apply the earlier patches (most importantly the fix)
and we'll see what shakes out as we address the outstanding
bugs in notifiers..