From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH 1/9] ipv6: implement dataplane support for rthdr type 4
 (Segment Routing Header)
Date: Mon, 17 Oct 2016 10:57:06 -0400 (EDT)
Message-ID: <20161017.105706.175400937082419121.davem@davemloft.net>
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To: david.lebrun@uclouvain.be
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From: David Lebrun <david.lebrun@uclouvain.be>
Date: Mon, 17 Oct 2016 16:42:22 +0200

> +/*
> + * SRH
> + */
> +struct ipv6_sr_hdr {
> +	__u8	nexthdr;
> +	__u8	hdrlen;
> +	__u8	type;
> +	__u8	segments_left;
> +	__u8	first_segment;
> +	__be16	flags;
> +	__u8	reserved;
> +
> +	struct in6_addr segments[0];
> +} __attribute__((packed));

Please don't use packed, it results in extremely inefficient code on
several architectures.

You can simply declare the flags as two 8-bit pieces and all will work
out fine.