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From:   Jason Wang <jasowang@redhat.com>
Date:   Thu, 10 Aug 2023 11:37:35 +0800
Message-ID: <CACGkMEuuEngqX6eKvRLvBm7_gGipVjfbkQ+JaXsE903CEkNfvA@mail.gmail.com>
Subject: Re: [PATCH v4] tun: avoid high-order page allocation for packet header
To:     Tahsin Erdogan <trdgn@amazon.com>
Cc:     Willem de Bruijn <willemdebruijn.kernel@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
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On Thu, Aug 10, 2023 at 12:48=E2=80=AFAM Tahsin Erdogan <trdgn@amazon.com> =
wrote:
>
> When gso.hdr_len is zero and a packet is transmitted via write() or
> writev(), all payload is treated as header which requires a contiguous
> memory allocation. This allocation request is harder to satisfy, and may
> even fail if there is enough fragmentation.
>
> Note that sendmsg() code path limits the linear copy length, so this chan=
ge
> makes write()/writev() and sendmsg() paths more consistent.
>
> Signed-off-by: Tahsin Erdogan <trdgn@amazon.com>
> ---
> v4: updated commit message address comments from Willem
> v3: rebase to latest net-next
> v2: replace linear =3D=3D 0 with !linear
> v1: https://lore.kernel.org/all/20230726030936.1587269-1-trdgn@amazon.com=
/

Acked-by: Jason Wang <jasowang@redhat.com>

Thanks