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Date: Wed, 9 Jul 2025 19:47:17 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Tariq Toukan <tariqt@nvidia.com>
Cc: Eric Dumazet <edumazet@google.com>, Paolo Abeni <pabeni@redhat.com>,
 Andrew Lunn <andrew+netdev@lunn.ch>, "David S. Miller"
 <davem@davemloft.net>, Saeed Mahameed <saeed@kernel.org>, Gal Pressman
 <gal@nvidia.com>, "Leon Romanovsky" <leon@kernel.org>, Saeed Mahameed
 <saeedm@nvidia.com>, Mark Bloch <mbloch@nvidia.com>,
 <netdev@vger.kernel.org>, <linux-rdma@vger.kernel.org>,
 <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH net-next 3/5] net/mlx5e: Replace recursive VLAN push
 handling with an iterative loop
Message-ID: <20250709194717.101a7a22@kernel.org>
In-Reply-To: <1752009387-13300-4-git-send-email-tariqt@nvidia.com>
References: <1752009387-13300-1-git-send-email-tariqt@nvidia.com>
	<1752009387-13300-4-git-send-email-tariqt@nvidia.com>
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On Wed, 9 Jul 2025 00:16:25 +0300 Tariq Toukan wrote:
> +		rcu_read_lock();
> +		*out_dev = dev_get_by_index_rcu(dev_net(vlan_dev),
> +						dev_get_iflink(vlan_dev));
> +		rcu_read_unlock();
> +		if (!*out_dev)
> +			return -ENODEV;
> +	} while (is_vlan_dev(*out_dev));

Would be good adding a comment here to explain why this odd rcu lock
/ lookup / rcu unlock / keep using the return value outside of rcu
protection - code flow is correct :S