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Date: Wed, 31 May 2023 11:16:02 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Qingfang DENG <dqfext@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>, Eric Dumazet
 <edumazet@google.com>, Paolo Abeni <pabeni@redhat.com>, YOSHIFUJI Hideaki
 <yoshfuji@linux-ipv6.org>, Ville Nuorvala <vnuorval@tcs.hut.fi>, Masahide
 NAKAMURA <nakam@linux-ipv6.org>, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org, Qingfang DENG <qingfang.deng@siflower.com.cn>
Subject: Re: [PATCH net] neighbour: fix unaligned access to pneigh_entry
Message-ID: <20230531111602.7ecf401b@kernel.org>
In-Reply-To: <20230531104233.50645-1-dqfext@gmail.com>
References: <20230531104233.50645-1-dqfext@gmail.com>
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On Wed, 31 May 2023 18:42:33 +0800 Qingfang DENG wrote:
> +#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
>  	u8			key[];
> +#else
> +	u8			key[] __aligned(4);
> +#endif

I'd appreciate a second opinion, but to me it's very unlikely we'd save
any memory even with efficient aligned access here. No reasonably key
will fit into 3 bytes, right? So we can as well avoid the ifdef and
make the key[] always aligned. Or preferably, if it doesn't cause
compilation issues, make the type of the key u32?