ath10k tx to a Macbook Pro stalls

[Andy Lutomirski]

On Mon, Jul 28, 2014 at 11:26 PM, Michal Kazior <michal.kazior at tieto.com> wrote:
> On 22 July 2014 06:12, Andy Lutomirski <luto at amacapital.net> wrote:
>> On Mon, Jul 21, 2014 at 11:31 AM, Kalle Valo <kvalo at qca.qualcomm.com> wrote:
>>> Andy Lutomirski <luto at amacapital.net> writes:
>>>
>>>> On my Archer C7 v2, as soon as the MBP tries to do something like
>>>> playing a video, it seems like frames *to* the MBP no longer get
>>>> there.  At the very least, arp replies don't get there.
>>>
>>> A multicast problem? Can you run for example 'arping -b <macbook's ip>'
>>> to check if multicast stops working at some point? What if you hardcode
>>> the ARP address, do unicast packets go to the macbook still?
>>
>> It's a unicast problem, actually.  arping -b works.  arping w/o -b
>> gets one reply.
>>
>> arp -s <IP> ff:ff:ff:ff:ff:ff allows me to ping the MBP (with
>> moderately high loss).  (I'm actually a bit surprised that Linux is
>> okay with that.)
>>
>> Does this mean that the MBP is failing to notice TIM entries, or that
>> ath10k somehow stops buffering packets to power-saving stations?
>
> Do you have u-APSD enabled in your OpenWRT configuration by any chance?

How do I tell?  The docs seem out of date here.  I have:

config wifi-device 'radio0'
    option type 'mac80211'
    option hwmode '11a'
    option path 'pci0000:01/0000:01:00.0'
    option htmode 'VHT80'
    #option htmode 'HT40'
    option disabled '0'
    option channel '149'

The relevant part (I think) of /var/run/hostapd.conf is:

ieee80211n=1
ht_capab=[HT40+][LDPC][SHORT-GI-20][SHORT-GI-40][TX-STBC][RX-STBC1][DSSS_CCK-40
]
vht_oper_chwidth=1
vht_oper_centr_freq_seg0_idx=155
ieee80211ac=1
vht_capab=[RXLDPC][SHORT-GI-80][TX-STBC-2BY1][RX-ANTENNA-PATTERN][TX-ANTENNA-PA
TTERN][RX-STBC1][MAX-MPDU-11454][MAX-A-MPDU-LEN-EXP7]

--Andy