netdev - [Question] Should NLMSG_DONE has flag NLM_F

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Message-ID: <YwWY8ux/PyMWQBWr@Laptop-X1>
Date:   Wed, 24 Aug 2022 11:20:18 +0800
From:   Hangbin Liu <liuhangbin@...il.com>
To:     netdev@...r.kernel.org
Cc:     Dmitry Safonov <0x7f454c46@...il.com>,
        Florian Westphal <fw@...len.de>,
        Arkadi Sharshevsky <arkadis@...lanox.com>
Subject: [Question] Should NLMSG_DONE has flag NLM_F_MULTI?

Hi,

When checking the NLMSG_DONE message in kernel, I saw lot of functions would
set NLM_F_MULTI flag. e.g. netlink_dump_done(),
devlink_dpipe_{tables, entries, headers}_fill().

But from rfc3549[1]:

   [...] For multipart
   messages, the first and all following headers have the NLM_F_MULTI
   Netlink header flag set, except for the last header which has the
   Netlink header type NLMSG_DONE.

What I understand is the last nlmsghdr(NLMSG_DONE message) doesn't need to
have NLM_F_MULTI flag. Am I missing something?

[1] https://www.rfc-editor.org/rfc/rfc3549.html#section-2.3.2

Thanks
Hangbin