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Date: Thu, 23 Apr 2026 10:36:28 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Sabrina Dubroca <sd@queasysnail.net>
Cc: Antonio Quartulli <antonio@openvpn.net>, netdev@vger.kernel.org, Ralf
 Lici <ralf@mandelbit.com>, Paolo Abeni <pabeni@redhat.com>, Andrew Lunn
 <andrew+netdev@lunn.ch>, "David S. Miller" <davem@davemloft.net>, Eric
 Dumazet <edumazet@google.com>, Hyunwoo Kim <imv4bel@gmail.com>
Subject: Re: [PATCH net 1/1] ovpn: fix race between deleting interface and
 adding new peer
Message-ID: <20260423103628.4ce6fc05@kernel.org>
In-Reply-To: <aepK3XXc8IFemb1Z@krikkit>
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On Thu, 23 Apr 2026 18:37:49 +0200 Sabrina Dubroca wrote:
> We could also wrap all of ovpn_peer_add (including the new reg_state
> check) in netdev_lock, since we can't move to NETREG_UNREGISTERING
> until netdev_lock is released (then I think we wouldn't need the
> READ_ONCE(reg_state)). But I don't know if that's an acceptable use of
> netdev_lock.

Yup, fwiw it's a perfectly legitimate use case.