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Date: Wed, 30 May 2018 12:03:19 +0200
From: Eugene Syromiatnikov <esyr@redhat.com>
To: Song Liu <liu.song.a23@gmail.com>
Cc: netdev@vger.kernel.org, open list <linux-kernel@vger.kernel.org>,
        Martin KaFai Lau <kafai@fb.com>,
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        Ingo Molnar <mingo@kernel.org>, Lawrence Brakmo <brakmo@fb.com>,
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        Jakub Kicinski <jakub.kicinski@netronome.com>,
        John Fastabend <john.fastabend@gmail.com>,
        "Dmitry V. Levin" <ldv@altlinux.org>
Subject: Re: [PATCH bpf 2/2] bpf: enforce usage of __aligned_u64 in the UAPI
 header
Message-ID: <20180530100319.GB5378@asgard.redhat.com>
References: <20180527112847.GA18311@asgard.redhat.com>
 <CAPhsuW5fVamngrqEWcsPKyr3Njjz4K5vO3o51BuWXAMw_nf9KA@mail.gmail.com>
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On Tue, May 29, 2018 at 10:35:09AM -0700, Song Liu wrote:
> I think these changes are not necessary. Is it a general guidance to
> only use 64-bit aligned
> variables in UAPI headers?

Not really, but it allows avoiding most alignment issues like the one
mentioned in the previous patch and in the referenced RDMA patch.