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Date: Mon, 25 Aug 2025 15:29:46 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Amery Hung <ameryhung@gmail.com>
Cc: Stanislav Fomichev <stfomichev@gmail.com>, bpf@vger.kernel.org,
 netdev@vger.kernel.org, alexei.starovoitov@gmail.com, andrii@kernel.org,
 daniel@iogearbox.net, martin.lau@kernel.org, mohsin.bashr@gmail.com,
 saeedm@nvidia.com, tariqt@nvidia.com, mbloch@nvidia.com,
 maciej.fijalkowski@intel.com, kernel-team@meta.com
Subject: Re: [RFC bpf-next v1 3/7] bpf: Support pulling non-linear xdp data
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	<aKzVsZ0D53rhOhQe@mini-arch>
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On Mon, 25 Aug 2025 15:23:23 -0700 Amery Hung wrote:
> > > +     if (!len)
> > > +             len = xdp_get_buff_len(xdp);  
> >
> > Why not return -EINVAL here for len=0?
> >  
> 
> I try to mirror the behavior of bpf_skb_pull_data() to reduce confusion here.

Different question for the same LoC :)

Why not

	if (!len)
		len = buff_len;
?
Or perhaps:

	len = len ?: buf_len;