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Message-ID: <8559ced4-cc59-4cbb-83c1-92bf7401cf0d@quicinc.com>
Date: Mon, 3 Jun 2024 10:47:16 +0800
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Subject: Re: [PATCH v3 6/8] wifi: ath12k: support ARP and NS offload
To: Jeff Johnson <quic_jjohnson@quicinc.com>, <ath12k@lists.infradead.org>
CC: <linux-wireless@vger.kernel.org>
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From: Baochen Qiang <quic_bqiang@quicinc.com>
In-Reply-To: <29f1a482-2ead-474a-93a1-00616bcf06f8@quicinc.com>
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On 6/1/2024 1:26 AM, Jeff Johnson wrote:
> On 5/30/2024 10:11 PM, Baochen Qiang wrote:
>>
>>
>> On 5/31/2024 11:42 AM, Baochen Qiang wrote:
>>>>> +static void ath12k_wow_prepare_ns_offload(struct ath12k_vif *arvif,
>>>>> +					  struct wmi_arp_ns_offload_arg *offload)
>>>>> +{
>>>>> +	struct inet6_dev *idev = arvif->idev;
>>>> as noted above does it make more sense to get the netdev associated with the
>>>> arvif and then use in6_dev_get(net_device) to get the inet6_dev rather than
>>>> caching the pointer from the ipv6_addr_changed() callback?
>>> Ah.. I didn't note that we can get inet6_dev in such a way, just thought the only way is to cache it in ipv6_changed() callback.
>>>
>>> will get it using the following in next version:
>>> 	struct ieee80211_vif *vif = container_of(arvif)
>>> 	struct ieee80211_sub_if_data *sub_if_data = container_of(vif)
>>> 	struct net_dev *ndev = sub_if_data->dev
>>> 	struct inet6_dev *idev = in6_dev_get(ndev)
>> Just found that ieee80211_sub_if_data is internal to mac80211, so not possible to get netdev in this way.
>>
>> any other ideas on how to get netdev?
> 
> Thinking about this some more, it seems like you'd want to send these down to
> firmware immediately so that they'd be available for NS offload. Does firmware
> support NS offload even when host is awake (I think the downstream Android
> driver supports that)?
Checked with firmware team and they confirmed it is supported. But do we really want to do this? Any benefit from offloading when awake?

And won't there be any issues? at least it would make me confused if a arp/NS request/response pair are seen in sniffer but neither of them seen in host ...
> So perhaps an alternative approach is to collect the information you need from
> the notification and then schedule a workqueue to actually send the
> information to firmware?