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Date: Thu, 17 Aug 2023 09:45:29 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Martin =?UTF-8?B?SHVuZGViw7hsbA==?= <martin@geanix.com>
Cc: Wolfgang Grandegger <wg@grandegger.com>, Marc Kleine-Budde
 <mkl@pengutronix.de>, "David S . Miller" <davem@davemloft.net>, Eric
 Dumazet <edumazet@google.com>, Paolo Abeni <pabeni@redhat.com>,
 Chandrasekar Ramakrishnan <rcsekar@samsung.com>, linux-can@vger.kernel.org,
 netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] can: netlink: support setting hardware filters
Message-ID: <20230817094529.68ae1083@kernel.org>
In-Reply-To: <20230817101014.3484715-2-martin@geanix.com>
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	<20230817101014.3484715-2-martin@geanix.com>
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On Thu, 17 Aug 2023 12:10:13 +0200 Martin Hundeb=C3=B8ll wrote:
> +		int len =3D nla_len(data[IFLA_CAN_HW_FILTER]);
> +		int num_filter =3D len / sizeof(struct can_filter);
> +		struct can_filter *filter =3D nla_data(data[IFLA_CAN_HW_FILTER]);

This will prevent you from ever extending struct can_filter in=20
a backward-compatible fashion, right? I obviously know very little
about CAN but are you confident a more bespoke API to manipulate
filters individually and allow extensibility is not warranted?