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Date: Sat, 8 Mar 2025 13:18:13 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Kohei Enju <enjuk@amazon.com>
Cc: <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
 <bpf@vger.kernel.org>, "David S . Miller" <davem@davemloft.net>, Eric
 Dumazet <edumazet@google.com>, Paolo Abeni <pabeni@redhat.com>, Simon
 Horman <horms@kernel.org>, Kuniyuki Iwashima <kuniyu@amazon.com>, Sebastian
 Andrzej Siewior <bigeasy@linutronix.de>, "Ahmed Zaki"
 <ahmed.zaki@intel.com>, Stanislav Fomichev <sdf@fomichev.me>, "Alexander
 Lobakin" <aleksander.lobakin@intel.com>, Kohei Enju <kohei.enju@gmail.com>
Subject: Re: [PATCH net-next v1] dev: remove netdev_lock() and
 netdev_lock_ops() in register_netdevice().
Message-ID: <20250308131813.4f8c8f0d@kernel.org>
In-Reply-To: <20250308203835.60633-2-enjuk@amazon.com>
References: <20250308203835.60633-2-enjuk@amazon.com>
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On Sun, 9 Mar 2025 05:37:18 +0900 Kohei Enju wrote:
> Both netdev_lock() and netdev_lock_ops() are called before
> list_netdevice() in register_netdevice().
> No other context can access the struct net_device, so we don't need these
> locks in this context.

Doesn't sysfs get registered earlier?
I'm afraid not being able to take the lock from the registration
path ties our hands too much. Maybe we need to make a more serious
attempt at letting the caller take the lock?