From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Ahern <dsahern@gmail.com>
Subject: Re: [PATCH net 05/10] net: xdp: don't allow device-bound programs in
 driver mode
Date: Mon, 20 Nov 2017 07:36:39 -0700
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References: <20171120045522.2188-1-jakub.kicinski@netronome.com>
 <20171120045522.2188-6-jakub.kicinski@netronome.com>
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Cc: alexei.starovoitov@gmail.com, daniel@iogearbox.net
To: Jakub Kicinski <jakub.kicinski@netronome.com>,
        netdev@vger.kernel.org
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On 11/19/17 9:55 PM, Jakub Kicinski wrote:
> diff --git a/net/core/dev.c b/net/core/dev.c
> index 09525a27319c..21de2d37a0ba 100644
> --- a/net/core/dev.c
> +++ b/net/core/dev.c
> @@ -7143,6 +7143,13 @@ int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,
>  					     bpf_op == ops->ndo_bpf);
>  		if (IS_ERR(prog))
>  			return PTR_ERR(prog);
> +
> +		if (!(flags & XDP_FLAGS_HW_MODE) &&
> +		    bpf_prog_is_dev_bound(prog->aux)) {
> +			NL_SET_ERR_MSG_MOD(extack, "using device-bound program without HW_MODE flag not supported");

I don't see dev_change_xdp_fd called by device drivers, so that should
just be NL_SET_ERR_MSG. Also, "is not supported" sounds better to me
than just "not supported".