From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jesper Dangaard Brouer <brouer@redhat.com>
Subject: Re: [net-next V7 PATCH 07/16] virtio_net: convert to use generic
 xdp_frame and xdp_return_frame API
Date: Sat, 31 Mar 2018 10:56:36 +0200
Message-ID: <20180331105636.228044c4@redhat.com>
References: <152234289201.17048.17760447330628182817.stgit@firesoul>
        <201803310253.4KzOXuLj%fengguang.wu@intel.com>
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        Jason Wang <jasowang@redhat.com>,
        John Fastabend <john.fastabend@gmail.com>,
        Eran Ben Elisha <eranbe@mellanox.com>,
        Saeed Mahameed <saeedm@mellanox.com>, galp@mellanox.com,
        Daniel Borkmann <borkmann@iogearbox.net>,
        Alexei Starovoitov <alexei.starovoitov@gmail.com>,
        Tariq Toukan <tariqt@mellanox.com>, brouer@redhat.com
To: kbuild test robot <lkp@intel.com>
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On Sat, 31 Mar 2018 02:22:35 +0800 kbuild test robot <lkp@intel.com> wrote:

> reproduce:
>         # apt-get install sparse
>         make ARCH=x86_64 allmodconfig
>         make C=1 CF=-D__CHECK_ENDIAN__

[...]
>    417	
>    418	static bool __virtnet_xdp_xmit(struct virtnet_info *vi,
>    419				       struct xdp_buff *xdp)
>    420	{
[...]
>    445	
>    446		/* Make room for virtqueue hdr (also change xdpf->headroom?) */
>    447		xdpf->data -= vi->hdr_len;
>    448		/* Zero header and leave csum up to XDP layers */
>    449		hdr = xdpf->data;
>    450		memset(hdr, 0, vi->hdr_len);
>  > 451		hdr->hdr.hdr_len = xdpf->len; /* Q: is this needed? */ 

I'll just remove this line, as Jason previously told me that it is not
strictly necessary (so lets avoid playing with endianness here).

>    452		xdpf->len   += vi->hdr_len;
>    453	

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer