A-MSDU reception not working?

Janusz Dziedzic janusz.dziedzic at tieto.com
Thu Jul 10 11:48:15 PDT 2014


On 10 July 2014 15:40, Denton Gentry <denton.gentry at gmail.com> wrote:
> I added this check for RX_ATTENTION_FLAGS_FCS_ERR in
> ath10k_htt_rx_handler, along with a printk to verify that the code was
> being run.
>
>                         if (attention & RX_ATTENTION_FLAGS_FCS_ERR) {
>                                 ath10k_htt_rx_free_msdu_chain(msdu_head);
>                                 printk(KERN_WARNING
> "ath10k_htt_rx_handler: amsdu RX_ATTENTION_FLAGS_FCS_ERR");
>                                 continue;
>                         } else
>                                 rx_status->flag &= ~RX_FLAG_FAILED_FCS_CRC;
>
> I see the printk appear in dmesg, so I know some packets are hitting
> it. The throughput from the MacOS 802.11ac STA does improve, from 5-20
> Mbps without to 50-60 Mbps with this change. Prior to adding the
> reorder buffer fix, the MacBook was getting 170 Mbps.
>
> However, packets with incorrect TCP checksums are still being
> delivered to the Ethernet connected server at the other end. I
> gathered pcaps at the MacBook, at the ath10k AP, on another ath10k
> device configured in monitor mode as a sniffer, and at the
> Ethernet-connected Ubuntu server at the other end.
>
Thanks for logs.

This is strange, this suggest MPDU have correct FCS, and only data in
MSDU are incorrect.
Seems like a FW/HW bug, while FCS was correct and other sniffer see
correct frame.
Seems also like not driver issue while this incorrect data are at
offset ~0x14C. In driver we touch mostly head and  tail of the data.
FW report IP/TCP checksum - interesting what status you get for such packet.
This is line:
skb->ip_summed = ath10k_htt_rx_get_csum_state(skb);

I see also this is QAM256 (5/6) - but FCS was correct so this suggest
MPDU frame was received correctly.
Interesting issue, I am curious who and when insert this wrong data.
Will check this more tomorrow.

BTW - this patch below is wrong, when we will start reorder we will
deliver only one MSDU - last one from AMSDU - instead of all, and all
with MORE flag will go directly to stack not waiting for reorder
decision. So could introduce other problems.

+       /* not impelemented correctly when driver report separete A-MSDUs */
+        if (status->flag & RX_FLAG_AMSDU_MORE)
+               goto dont_reorder;
+

So we have 3 options in case of using mac80211 reordering:
1) use big frame (memcpy overhead)
2) report amsd as a skb list (not sure mac80211 patches will be merged
- under discussion)
3) rewrite mac80211 reordering code to support AMSDU_MORE correctly

Other option can be, put reordering code in the driver (table for each
mpdu for peer and for each tid - resources required - while we have
almost the same allocated in mac80211 already)

BR
Janusz

>
> server.pcap
> Captured from the Ubuntu iperf server, connected to the AP via Ethernet.
>
> Packet #10: TCP seq 4369, IP ID 0x6373, TCP checksum incorrect
> At offset 208 bytes into the data we see “32 33 34 35” replaced by “98 19 1e b7”
>
> Packet #17: TCP seq 4369, IP ID 0x6373, TCP checksum correct
> Packet #23: TCP seq 4369, IP ID 0xe152, TCP checksum correct
>
>
> ap.pcap
> Captured from the AP.
>
> Packet #10: TCP seq 4369, IP ID 0x6373, TCP checksum incorrect
> At offset 208 bytes into the data we see “32 33 34 35” replaced by “98 19 1e b7”
> This is the same pattern we see in the Ubuntu server's trace.
>
> Packet #14: TCP seq 4369, IP ID 0x6373, TCP checksum correct
> This was a Wifi-layer retransmit, which I think means the firmware
> knew that something was wrong with packet #10. In the wifisniffer
> trace, packet #19 is a Block ACK from the AP which requests one packet
> be retransmitted.
> However it appears that RX_ATTENTION_FLAGS_FCS_ERR was not set on
> packet #10, so it was forwarded to the Ethernet.
>
> Packet #24: TCP seq 4369, IP ID 0xe152, TCP checksum correct
> This is a TCP-layer retransmit from the MacBook, as the IP ID is different.
>
>
> wifisniffer.pcap
> A second ath10 configured in monitor mode.
> Packet #17 AMSDU#1: TCP seq 4369, IP ID 0x6373, TCP checksum correct
> This is packet #10 in the AP trace. Note that the sniffer did not see
> “98 19 1e b7” like the AP did.
>
> Packet #20 AMSDU#1: TCP seq 4369, IP ID 0x6373, TCP checksum correct
> This is packet #14 in the AP trace.
>
> Packet #39 AMSDU#2: TCP seq 4369, IP ID 0xe152, TCP checksum correct
> This is packet #24 in the AP trace.
>
>
> macbook.pcapng
> 56: TCP seq 4369, IP ID 0x6373, TCP checksum correct
> This is the original transmission. Wireshark on MacOS cannot put the
> interface into monitor mode, so we do not see the Wifi-layer
> retransmission of this packet.
>
> 65: TCP seq 4369, IP ID 0xe152, TCP checksum correct
> This is a TCP retransmission, triggered because it received duplicate
> TCP ACKs back from the Ubuntu server.
>
>
> On Wed, Jul 9, 2014 at 12:39 AM, Janusz Dziedzic
> <janusz.dziedzic at tieto.com> wrote:
>> On 9 July 2014 08:09, Denton Gentry <denton.gentry at gmail.com> wrote:
>>> I ran iperf on an 802.11ac MacBook Air, through my ath10 AP, and to an
>>> Ubuntu system connected to the AP via Ethernet. The AP was running the
>>> reorder buffer patches, the patch to make A-MSDU bypass the reorder
>>> buffer, and the patch to make amsdu aggregation configurable via
>>> debugfs.
>>>
>>> http://lists.infradead.org/pipermail/ath10k/2014-June/002551.html
>>> http://lists.infradead.org/pipermail/ath10k/2014-June/002553.html
>>> http://lists.infradead.org/pipermail/ath10k/2014-July/002597.html
>>> http://permalink.gmane.org/gmane.linux.kernel.wireless.general/124128
>>>
>>> It was notably not running the patch from earlier in this thread to
>>> copy A-MSDU subframes into one skb.
>>>
>>>
>>> I used a second ath10k AP configured in monitor mode as a Wifi
>>> sniffer. I also gathered pcaps on the MacBook Air and on the Ubuntu
>>> system. Wireshark on the MacBook cannot gather radiotap headers nor
>>> put the interface into monitor mode, so we see only Ethernet frames
>>> and we don't see retransmissions on the Wifi link.
>>>
>>> I've attached decodes of the same two packets as captured by the
>>> MacBook, by the sniffer, and by the Ubuntu server.
>>>
>>> The MacBook sends two frames, TCP sequence numbers 3065441 and 3066889
>>> (the Wireshark "relative sequence number"). In the Wifi sniffer we see
>>> these being aggregated as two subframes in an A-MSDU frame. The first
>>> time this A-MSDU is sent it is corrupted in the air. We see the TCP
>>> checksum of one of the subframes is wrong, and a few bytes of the
>>> payload replaced with "&gt%'g9(1$".
>>>
>>> The A-MSDU is retransmitted a short time later, and the second time
>>> the TCP checksum of both subframes is correct.
>>>
>>> This is all fine so far.
>>>
>>> However in the pcap taken from the Ubuntu server, we see TCP sequence
>>> number 3065441 being delivered *twice.* The first time, the TCP
>>> checksum is wrong. The second time the TCP checksum is correct.
>>>
>>> To me, it looks like A-MSDU frames with bad FCS are not being
>>> discarded after ieee80211_rx_monitor(). The corrupted frames are being
>>> delivered. Delivering the corrupted frames results in sending more TCP
>>> Dup ACKs for the same sequence number back to the MacBook, and I think
>>> this is what causes the MacBook to decide there is congestion and slow
>>> down.
>>>
>> OK, to be sure this is the main issue we can just drop frames with wrong FCS.
>> Could you check this:
>>
>> @@ -1267,10 +1267,10 @@ static void ath10k_htt_rx_handler(struct
>> ath10k_htt *htt,
>>                                 continue;
>>                         }
>>
>> -                       if (attention & RX_ATTENTION_FLAGS_FCS_ERR)
>> -                               rx_status->flag |= RX_FLAG_FAILED_FCS_CRC;
>> -                       else
>> -                               rx_status->flag &= ~RX_FLAG_FAILED_FCS_CRC;
>> +                       if (attention & RX_ATTENTION_FLAGS_FCS_ERR) {
>> +                               ath10k_htt_rx_free_msdu_chain(msdu_head);
>> +                               continue;
>> +                       }
>>
>>                         if (attention & RX_ATTENTION_FLAGS_TKIP_MIC_ERR)
>>
>> If will help we will have to check how to handle monitor + ap case
>> correctly, one of idea is to not drop frames with wrong FCS only in
>> case of standalone monitor mode.
>> But, please try this patch to be sure.
>>
>> BR
>> Janusz
>>
>>
>>> One note: the wifi sniffer does not show the same corruption to the
>>> same packet as the pcap from the Ubuntu system shows. I think that is
>>> normal: the sniffer won't see precisely the same noise, won't have
>>> precisely the same receive sensitivity, and its antennas are not
>>> pointing in the same direction as the primary AP. If I do this test
>>> again, I'll gather a pcap on the primary AP as well to compare to what
>>> we see on the Ubuntu system.
>>>
>>>
>>> On Tue, Jul 8, 2014 at 12:29 AM, Janusz Dziedzic
>>> <janusz.dziedzic at tieto.com> wrote:
>>>> On 8 July 2014 09:02, Janusz Dziedzic <janusz.dziedzic at tieto.com> wrote:
>>>>> On 8 July 2014 08:50, Janusz Dziedzic <janusz.dziedzic at tieto.com> wrote:
>>>>>> On 8 July 2014 08:43, Denton Gentry <denton.gentry at gmail.com> wrote:
>>>>>>> I think I know what is happening now, though I've no idea why. The
>>>>>>> throughput is low because we have many TCP retransmissions. We have
>>>>>>> retransmissions because the TCP checksum is wrong on a number of
>>>>>>> frames, and I do find data corruption in the payload so the checksum
>>>>>>> definitely should be wrong. All of the corrupted frames were
>>>>>>> originally one of the subframes in an A-MSDU packet.
>>>>>>>
>>>>>>> An example follows at the end of this message, as dissected by
>>>>>>> Wireshark. iperf sends a very regular data pattern of "0123456789..."
>>>>>>> over and over. Note how in subframe #2 offset 0x1e0 the bytes "32 33
>>>>>>> 34" have been replaced by "72 36 35"
>>>>>>>
>>>>>>> 01e0  32 33 34 35 36 37 38 39 30 31 72 36 35 35 36 37   2345678901r65567
>>>>>>>
>>>>>>> I added printks at the bottom of ath10k_htt_rx_amsdu immediately
>>>>>>> before the call to ath10k_process_rx. I found this same packet, and we
>>>>>>> see the "72 36 35" corruption in the printk. So I think it happened in
>>>>>>> ath10k_process_rx or before, not anything weird after passing it up to
>>>>>>> mac80211.
>>>>>>>
>>>>>>> [  101.863712] ath10k: 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39 30
>>>>>>> [  101.863727] ath10k: 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35 36
>>>>>>> [  101.863742] ath10k: 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31 32
>>>>>>> [  101.863757] ath10k: 33 34 35 36 37 38 39 30 31 72 36 35 35 36 37 38
>>>>>>> [  101.863773] ath10k: 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33 34
>>>>>>> [  101.863788] ath10k: 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39 30
>>>>>>> [  101.863803] ath10k: 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35 36
>>>>>>>
>>>>>>>
>>>>>>> I've found a number of examples of similar corruption, always with
>>>>>>> between one and four bytes replaced.
>>>>>>>
>>>>>>> 35363738 -> e52c6e07
>>>>>>> 3435 -> b43f
>>>>>>> 3839 -> c238
>>>>>>> 31 -> 7f
>>>>>>> 3435 -> 7436
>>>>>>> 30 -> 50
>>>>>>> 3233 -> bc37
>>>>>>>
>>>>>> Seems this could be because of:
>>>>>>
>>>>>> + /* cfg80211 expect this padding */
>>>>>> + padding = (4 - (skb->len + sizeof(subframe_hdr))) & 0x3;
>>>>>> + skb_put(skb, padding);
>>>>>>
>>>>>
>>>>> BTW, when AP (ath10k) send TCP ACK - are this packets also AMSDU?
>>>>> I see in my case AP can send 3 x A-MSDU (with total size 304 bytes)
>>>>> small frames aggregated. Maybe your HW have problems with that.
>>>>> As I remember correctly someone some time ago report problems with
>>>>> MacBook pro retina but I am not sure this is the same, while no one
>>>>> tests the fix.
>>>>>
>>>>>>>
>>>>>>> The packet described above, dissected by Wireshark:
>>>>>>>
>>>>>>> No.     Time        Source                Destination
>>>>>>> Protocol Length Info
>>>>>>>    2235 18.953349   192.168.144.79        192.168.144.13        TCP
>>>>>>>   3112   52697 > 5001 [ACK] Seq=1391553 Ack=1 Win=131760 [TCP CHECKSUM
>>>>>>> INCORRECT] Len=1448 TSval=1298580657 TSecr=4294947481
>>>>>>>
>>>>>>> Frame 2235: 3112 bytes on wire (24896 bits), 3112 bytes captured (24896 bits)
>>>>>>>     Encapsulation type: IEEE 802.11 plus radiotap radio header (23)
>>>>>>>     Arrival Time: Jul  7, 2014 23:03:37.763365000 PDT
>>>>>>>     [Time shift for this packet: 0.000000000 seconds]
>>>>>>>     Epoch Time: 1404799417.763365000 seconds
>>>>>>>     [Time delta from previous captured frame: 0.003476000 seconds]
>>>>>>>     [Time delta from previous displayed frame: 0.515641000 seconds]
>>>>>>>     [Time since reference or first frame: 18.953349000 seconds]
>>>>>>>     Frame Number: 2235
>>>>>>>     Frame Length: 3112 bytes (24896 bits)
>>>>>>>     Capture Length: 3112 bytes (24896 bits)
>>>>>>>     [Frame is marked: False]
>>>>>>>     [Frame is ignored: False]
>>>>>>>     [Protocols in frame: radiotap:wlan:llc:ip:tcp:data:llc:ip:tcp:data]
>>>>>>>     [Coloring Rule Name: TCP]
>>>>>>>     [Coloring Rule String: tcp]
>>>>>>> Radiotap Header v0, Length 38
>>>>>>>     Header revision: 0
>>>>>>>     Header pad: 0
>>>>>>>     Header length: 38
>>>>>>>     Present flags
>>>>>>>         .... .... .... .... .... .... .... ...1 = TSFT: True
>>>>>>>         .... .... .... .... .... .... .... ..1. = Flags: True
>>>>>>>         .... .... .... .... .... .... .... .0.. = Rate: False
>>>>>>>         .... .... .... .... .... .... .... 1... = Channel: True
>>>>>>>         .... .... .... .... .... .... ...0 .... = FHSS: False
>>>>>>>         .... .... .... .... .... .... ..1. .... = dBm Antenna Signal: True
>>>>>>>         .... .... .... .... .... .... .0.. .... = dBm Antenna Noise: False
>>>>>>>         .... .... .... .... .... .... 0... .... = Lock Quality: False
>>>>>>>         .... .... .... .... .... ...0 .... .... = TX Attenuation: False
>>>>>>>         .... .... .... .... .... ..0. .... .... = dB TX Attenuation: False
>>>>>>>         .... .... .... .... .... .0.. .... .... = dBm TX Power: False
>>>>>>>         .... .... .... .... .... 1... .... .... = Antenna: True
>>>>>>>         .... .... .... .... ...0 .... .... .... = dB Antenna Signal: False
>>>>>>>         .... .... .... .... ..0. .... .... .... = dB Antenna Noise: False
>>>>>>>         .... .... .... .... .1.. .... .... .... = RX flags: True
>>>>>>>         .... .... .... .0.. .... .... .... .... = Channel+: False
>>>>>>>         .... .... .... 0... .... .... .... .... = HT information: False
>>>>>>>         .... .... ...0 .... .... .... .... .... = A-MPDU Status: False
>>>>>>>         .... .... ..1. .... .... .... .... .... = VHT information: True
>>>>>>>         ...0 0000 00.. .... .... .... .... .... = Reserved: 0x00000000
>>>>>>>         ..0. .... .... .... .... .... .... .... = Radiotap NS next: False
>>>>>>>         .0.. .... .... .... .... .... .... .... = Vendor NS next: False
>>>>>>>         0... .... .... .... .... .... .... .... = Ext: False
>>>>>>>     MAC timestamp: 78051063
>>>>>>>     Flags: 0x00
>>>>>>>         .... ...0 = CFP: False
>>>>>>>         .... ..0. = Preamble: Long
>>>>>>>         .... .0.. = WEP: False
>>>>>>>         .... 0... = Fragmentation: False
>>>>>>>         ...0 .... = FCS at end: False
>>>>>>>         ..0. .... = Data Pad: False
>>>>>>>         .0.. .... = Bad FCS: False
>>>>>>>         0... .... = Short GI: False
>>>>>>>     Channel frequency: 5745 [A 149]
>>>>>>>     Channel type: 802.11a (0x0140)
>>>>>>>         .... .... ...0 .... = Turbo: False
>>>>>>>         .... .... ..0. .... = Complementary Code Keying (CCK): False
>>>>>>>         .... .... .1.. .... = Orthogonal Frequency-Division
>>>>>>> Multiplexing (OFDM): True
>>>>>>>         .... .... 0... .... = 2 GHz spectrum: False
>>>>>>>         .... ...1 .... .... = 5 GHz spectrum: True
>>>>>>>         .... ..0. .... .... = Passive: False
>>>>>>>         .... .0.. .... .... = Dynamic CCK-OFDM: False
>>>>>>>         .... 0... .... .... = Gaussian Frequency Shift Keying (GFSK): False
>>>>>>>         ...0 .... .... .... = GSM (900MHz): False
>>>>>>>         ..0. .... .... .... = Static Turbo: False
>>>>>>>         .0.. .... .... .... = Half Rate Channel (10MHz Channel Width): False
>>>>>>>         0... .... .... .... = Quarter Rate Channel (5MHz Channel Width): False
>>>>>>>     SSI Signal: -53 dBm
>>>>>>>     Antenna: 0
>>>>>>>     RX flags: 0x0000
>>>>>>>         .... .... .... .... .... ..0. = Bad PLCP: False
>>>>>>>     VHT information
>>>>>>>         Known VHT information: 0x44
>>>>>>>             .... .... .... ...0 = STBC: False
>>>>>>>             .... .... .... ..0. = TXOP_PS_NOT_ALLOWED: False
>>>>>>>             .... .... .... .1.. = Guard interval: True
>>>>>>>             .... .... .... 0... = SGI Nsym disambiguation: False
>>>>>>>             .... .... ...0 .... = LDPC extra OFDM symbol: False
>>>>>>>             .... .... ..0. .... = Beamformed: False
>>>>>>>             .... .... .1.. .... = Bandwidth: True
>>>>>>>             .... .... 0... .... = Group ID: False
>>>>>>>             .... ...0 .... .... = Partial AID: False
>>>>>>>         .... .0.. = Guard interval: long (0)
>>>>>>>         Bandwidth: 80 MHz (4)
>>>>>>>         User 0: MCS 8
>>>>>>>             1000 .... = MCS index 0: 8 (256-QAM 3/4)
>>>>>>>             .... 0010 = Spatial streams 0: 2
>>>>>>>             Space-time streams 0: 2
>>>>>>>             Coding 0: BCC (0)
>>>>>>>             [Data Rate: 702.0 Mb/s]
>>>>>>> IEEE 802.11 QoS Data, Flags: .......T
>>>>>>>     Type/Subtype: QoS Data (0x28)
>>>>>>>     Frame Control Field: 0x8801
>>>>>>>         .... ..00 = Version: 0
>>>>>>>         .... 10.. = Type: Data frame (2)
>>>>>>>         1000 .... = Subtype: 8
>>>>>>>         Flags: 0x01
>>>>>>>             .... ..01 = DS status: Frame from STA to DS via an AP (To
>>>>>>> DS: 1 From DS: 0) (0x01)
>>>>>>>             .... .0.. = More Fragments: This is the last fragment
>>>>>>>             .... 0... = Retry: Frame is not being retransmitted
>>>>>>>             ...0 .... = PWR MGT: STA will stay up
>>>>>>>             ..0. .... = More Data: No data buffered
>>>>>>>             .0.. .... = Protected flag: Data is not protected
>>>>>>>             0... .... = Order flag: Not strictly ordered
>>>>>>>     .000 0000 0011 0000 = Duration: 48 microseconds
>>>>>>>     Receiver address: SenaoNet_18:a8:00 (88:dc:96:18:a8:00)
>>>>>>>     BSS Id: SenaoNet_18:a8:00 (88:dc:96:18:a8:00)
>>>>>>>     Transmitter address: Apple_67:24:54 (84:38:35:67:24:54)
>>>>>>>     Source address: Apple_67:24:54 (84:38:35:67:24:54)
>>>>>>>     Destination address: SenaoNet_18:a8:00 (88:dc:96:18:a8:00)
>>>>>>>     Fragment number: 0
>>>>>>>     Sequence number: 1021
>>>>>>>     Qos Control: 0x0080
>>>>>>>         .... .... .... 0000 = TID: 0
>>>>>>>         [.... .... .... .000 = Priority: Best Effort (Best Effort) (0)]
>>>>>>>         .... .... ...0 .... = QoS bit 4: Bits 8-15 of QoS Control
>>>>>>> field are TXOP Duration Requested
>>>>>>>         .... .... .00. .... = Ack Policy: Normal Ack (0x0000)
>>>>>>>         .... .... 1... .... = Payload Type: A-MSDU
>>>>>>>         0000 0000 .... .... = TXOP Duration Requested: 0 (no TXOP requested)
>>>>>>> IEEE 802.11 Aggregate MSDU
>>>>>>>     A-MSDU Subframe #1
>>>>>>>         Destination address: GoogleFi_00:14:cd (f8:8f:ca:00:14:cd)
>>>>>>>         Source address: Apple_67:24:54 (84:38:35:67:24:54)
>>>>>>>         A-MSDU Length: 1510
>>>>>>>         Logical-Link Control
>>>>>>>             DSAP: SNAP (0xaa)
>>>>>>>             IG Bit: Individual
>>>>>>>             SSAP: SNAP (0xaa)
>>>>>>>             CR Bit: Command
>>>>>>>             Control field: U, func=UI (0x03)
>>>>>>>                 000. 00.. = Command: Unnumbered Information (0x00)
>>>>>>>                 .... ..11 = Frame type: Unnumbered frame (0x03)
>>>>>>>             Organization Code: Encapsulated Ethernet (0x000000)
>>>>>>>             Type: IP (0x0800)
>>>>>>>         Internet Protocol Version 4, Src: 192.168.144.79
>>>>>>> (192.168.144.79), Dst: 192.168.144.13 (192.168.144.13)
>>>>>>>             Version: 4
>>>>>>>             Header length: 20 bytes
>>>>>>>             Differentiated Services Field: 0x00 (DSCP 0x00: Default;
>>>>>>> ECN: 0x00: Not-ECT (Not ECN-Capable Transport))
>>>>>>>                 0000 00.. = Differentiated Services Codepoint: Default (0x00)
>>>>>>>                 .... ..00 = Explicit Congestion Notification: Not-ECT
>>>>>>> (Not ECN-Capable Transport) (0x00)
>>>>>>>             Total Length: 1500
>>>>>>>             Identification: 0xc622 (50722)
>>>>>>>             Flags: 0x00
>>>>>>>                 0... .... = Reserved bit: Not set
>>>>>>>                 .0.. .... = Don't fragment: Not set
>>>>>>>                 ..0. .... = More fragments: Not set
>>>>>>>             Fragment offset: 0
>>>>>>>             Time to live: 64
>>>>>>>             Protocol: TCP (6)
>>>>>>>             Header checksum: 0x0d4c [correct]
>>>>>>>                 [Good: True]
>>>>>>>                 [Bad: False]
>>>>>>>             Source: 192.168.144.79 (192.168.144.79)
>>>>>>>             Destination: 192.168.144.13 (192.168.144.13)
>>>>>>>             [Source GeoIP: Unknown]
>>>>>>>             [Destination GeoIP: Unknown]
>>>>>>>         Transmission Control Protocol, Src Port: 52697 (52697), Dst
>>>>>>> Port: 5001 (5001), Seq: 1390105, Ack: 1, Len: 1448
>>>>>>>             Source port: 52697 (52697)
>>>>>>>             Destination port: 5001 (5001)
>>>>>>>             [Stream index: 0]
>>>>>>>             Sequence number: 1390105    (relative sequence number)
>>>>>>>             [Next sequence number: 1391553    (relative sequence number)]
>>>>>>>             Acknowledgment number: 1    (relative ack number)
>>>>>>>             Header length: 32 bytes
>>>>>>>             Flags: 0x010 (ACK)
>>>>>>>                 000. .... .... = Reserved: Not set
>>>>>>>                 ...0 .... .... = Nonce: Not set
>>>>>>>                 .... 0... .... = Congestion Window Reduced (CWR): Not set
>>>>>>>                 .... .0.. .... = ECN-Echo: Not set
>>>>>>>                 .... ..0. .... = Urgent: Not set
>>>>>>>                 .... ...1 .... = Acknowledgment: Set
>>>>>>>                 .... .... 0... = Push: Not set
>>>>>>>                 .... .... .0.. = Reset: Not set
>>>>>>>                 .... .... ..0. = Syn: Not set
>>>>>>>                 .... .... ...0 = Fin: Not set
>>>>>>>             Window size value: 8235
>>>>>>>             [Calculated window size: 131760]
>>>>>>>             [Window size scaling factor: 16]
>>>>>>>             Checksum: 0xa1c0 [correct]
>>>>>>>                 [Good Checksum: True]
>>>>>>>                 [Bad Checksum: False]
>>>>>>>             Options: (12 bytes), No-Operation (NOP), No-Operation
>>>>>>> (NOP), Timestamps
>>>>>>>                 No-Operation (NOP)
>>>>>>>                     Type: 1
>>>>>>>                         0... .... = Copy on fragmentation: No
>>>>>>>                         .00. .... = Class: Control (0)
>>>>>>>                         ...0 0001 = Number: No-Operation (NOP) (1)
>>>>>>>                 No-Operation (NOP)
>>>>>>>                     Type: 1
>>>>>>>                         0... .... = Copy on fragmentation: No
>>>>>>>                         .00. .... = Class: Control (0)
>>>>>>>                         ...0 0001 = Number: No-Operation (NOP) (1)
>>>>>>>                 Timestamps: TSval 1298580657, TSecr 4294947481
>>>>>>>                     Kind: Timestamp (8)
>>>>>>>                     Length: 10
>>>>>>>                     Timestamp value: 1298580657
>>>>>>>                     Timestamp echo reply: 4294947481
>>>>>>>         Data (1448 bytes)
>>>>>>>
>>>>>>> 0000  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0010  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0020  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0030  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0040  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0050  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0060  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0070  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0080  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0090  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 00a0  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 00b0  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 00c0  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 00d0  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 00e0  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 00f0  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0100  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0110  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0120  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0130  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0140  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0150  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0160  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0170  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0180  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0190  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 01a0  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 01b0  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 01c0  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 01d0  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 01e0  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 01f0  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0200  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0210  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0220  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0230  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0240  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0250  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0260  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0270  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0280  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0290  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 02a0  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 02b0  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 02c0  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 02d0  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 02e0  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 02f0  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0300  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0310  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0320  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0330  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0340  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0350  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0360  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0370  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0380  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0390  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 03a0  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 03b0  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 03c0  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 03d0  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 03e0  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 03f0  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0400  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0410  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0420  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0430  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0440  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0450  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0460  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0470  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0480  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0490  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 04a0  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 04b0  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 04c0  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 04d0  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 04e0  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 04f0  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0500  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0510  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0520  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0530  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0540  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0550  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0560  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0570  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0580  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0590  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 05a0  34 35 36 37 38 39 30 31                           45678901
>>>>>>>             Data: 343536373839303132333435363738393031323334353637...
>>>>>>>             [Length: 1448]
>>>>>>>     A-MSDU Subframe #2
>>>>>>>         Destination address: GoogleFi_00:14:cd (f8:8f:ca:00:14:cd)
>>>>>>>         Source address: Apple_67:24:54 (84:38:35:67:24:54)
>>>>>>>         A-MSDU Length: 1510
>>>>>>>         Logical-Link Control
>>>>>>>             DSAP: SNAP (0xaa)
>>>>>>>             IG Bit: Individual
>>>>>>>             SSAP: SNAP (0xaa)
>>>>>>>             CR Bit: Command
>>>>>>>             Control field: U, func=UI (0x03)
>>>>>>>                 000. 00.. = Command: Unnumbered Information (0x00)
>>>>>>>                 .... ..11 = Frame type: Unnumbered frame (0x03)
>>>>>>>             Organization Code: Encapsulated Ethernet (0x000000)
>>>>>>>             Type: IP (0x0800)
>>>>>>>         Internet Protocol Version 4, Src: 192.168.144.79
>>>>>>> (192.168.144.79), Dst: 192.168.144.13 (192.168.144.13)
>>>>>>>             Version: 4
>>>>>>>             Header length: 20 bytes
>>>>>>>             Differentiated Services Field: 0x00 (DSCP 0x00: Default;
>>>>>>> ECN: 0x00: Not-ECT (Not ECN-Capable Transport))
>>>>>>>                 0000 00.. = Differentiated Services Codepoint: Default (0x00)
>>>>>>>                 .... ..00 = Explicit Congestion Notification: Not-ECT
>>>>>>> (Not ECN-Capable Transport) (0x00)
>>>>>>>             Total Length: 1500
>>>>>>>             Identification: 0xda09 (55817)
>>>>>>>             Flags: 0x00
>>>>>>>                 0... .... = Reserved bit: Not set
>>>>>>>                 .0.. .... = Don't fragment: Not set
>>>>>>>                 ..0. .... = More fragments: Not set
>>>>>>>             Fragment offset: 0
>>>>>>>             Time to live: 64
>>>>>>>             Protocol: TCP (6)
>>>>>>>             Header checksum: 0xf964 [correct]
>>>>>>>                 [Good: True]
>>>>>>>                 [Bad: False]
>>>>>>>             Source: 192.168.144.79 (192.168.144.79)
>>>>>>>             Destination: 192.168.144.13 (192.168.144.13)
>>>>>>>             [Source GeoIP: Unknown]
>>>>>>>             [Destination GeoIP: Unknown]
>>>>>>>         Transmission Control Protocol, Src Port: 52697 (52697), Dst
>>>>>>> Port: 5001 (5001), Seq: 1391553, Ack: 1, Len: 1448
>>>>>>>             Source port: 52697 (52697)
>>>>>>>             Destination port: 5001 (5001)
>>>>>>>             [Stream index: 0]
>>>>>>>             Sequence number: 1391553    (relative sequence number)
>>>>>>>             [Next sequence number: 1393001    (relative sequence number)]
>>>>>>>             Acknowledgment number: 1    (relative ack number)
>>>>>>>             Header length: 32 bytes
>>>>>>>             Flags: 0x010 (ACK)
>>>>>>>                 000. .... .... = Reserved: Not set
>>>>>>>                 ...0 .... .... = Nonce: Not set
>>>>>>>                 .... 0... .... = Congestion Window Reduced (CWR): Not set
>>>>>>>                 .... .0.. .... = ECN-Echo: Not set
>>>>>>>                 .... ..0. .... = Urgent: Not set
>>>>>>>                 .... ...1 .... = Acknowledgment: Set
>>>>>>>                 .... .... 0... = Push: Not set
>>>>>>>                 .... .... .0.. = Reset: Not set
>>>>>>>                 .... .... ..0. = Syn: Not set
>>>>>>>                 .... .... ...0 = Fin: Not set
>>>>>>>             Window size value: 8235
>>>>>>>             [Calculated window size: 131760]
>>>>>>>             [Window size scaling factor: 16]
>>>>>>>             Checksum: 0x9a16 [incorrect, should be 0x5913 (maybe
>>>>>>> caused by "TCP checksum offload"?)]
>>>>
>>>> And yes we are using checksum offload in ath10k.
>>>> Best is using standalone 80211ac sniffer for that case to be sure
>>>> about checksum.
>>>>
>>>>>>>                 [Good Checksum: False]
>>>>>>>                 [Bad Checksum: True]
>>>>>>>                     [Expert Info (Error/Checksum): Bad checksum]
>>>>>>>                         [Message: Bad checksum]
>>>>>>>                         [Severity level: Error]
>>>>>>>                         [Group: Checksum]
>>>>>>>             Options: (12 bytes), No-Operation (NOP), No-Operation
>>>>>>> (NOP), Timestamps
>>>>>>>                 No-Operation (NOP)
>>>>>>>                     Type: 1
>>>>>>>                         0... .... = Copy on fragmentation: No
>>>>>>>                         .00. .... = Class: Control (0)
>>>>>>>                         ...0 0001 = Number: No-Operation (NOP) (1)
>>>>>>>                 No-Operation (NOP)
>>>>>>>                     Type: 1
>>>>>>>                         0... .... = Copy on fragmentation: No
>>>>>>>                         .00. .... = Class: Control (0)
>>>>>>>                         ...0 0001 = Number: No-Operation (NOP) (1)
>>>>>>>                 Timestamps: TSval 1298580657, TSecr 4294947481
>>>>>>>                     Kind: Timestamp (8)
>>>>>>>                     Length: 10
>>>>>>>                     Timestamp value: 1298580657
>>>>>>>                     Timestamp echo reply: 4294947481
>>>>>>>         Data (1448 bytes)
>>>>>>>
>>>>>>> 0000  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0010  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0020  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0030  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0040  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0050  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0060  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0070  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0080  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0090  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 00a0  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 00b0  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 00c0  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 00d0  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 00e0  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 00f0  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0100  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0110  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0120  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0130  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0140  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0150  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0160  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0170  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0180  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0190  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 01a0  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 01b0  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 01c0  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 01d0  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 01e0  32 33 34 35 36 37 38 39 30 31 72 36 35 35 36 37   2345678901r65567
>>>>>>> 01f0  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0200  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0210  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0220  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0230  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0240  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0250  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0260  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0270  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0280  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0290  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 02a0  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 02b0  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 02c0  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 02d0  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 02e0  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 02f0  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0300  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0310  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0320  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0330  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0340  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0350  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0360  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0370  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0380  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0390  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 03a0  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 03b0  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 03c0  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 03d0  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 03e0  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 03f0  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0400  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0410  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0420  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0430  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0440  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0450  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0460  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0470  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0480  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0490  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 04a0  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 04b0  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 04c0  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 04d0  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 04e0  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 04f0  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0500  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0510  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0520  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0530  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0540  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 0550  32 33 34 35 36 37 38 39 30 31 32 33 34 35 36 37   2345678901234567
>>>>>>> 0560  38 39 30 31 32 33 34 35 36 37 38 39 30 31 32 33   8901234567890123
>>>>>>> 0570  34 35 36 37 38 39 30 31 32 33 34 35 36 37 38 39   4567890123456789
>>>>>>> 0580  30 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35   0123456789012345
>>>>>>> 0590  36 37 38 39 30 31 32 33 34 35 36 37 38 39 30 31   6789012345678901
>>>>>>> 05a0  32 33 34 35 36 37 38 39                           23456789
>>>>>>>             Data: 323334353637383930313233343536373839303132333435...
>>>>>>>             [Length: 1448]
>>>>>>>
>>>>>>> On Mon, Jul 7, 2014 at 12:26 PM, Denton Gentry <denton.gentry at gmail.com> wrote:
>>>>>>>> The initial results are not promising: a MacOS 802.11ac client gets
>>>>>>>> between 0-2 Mbps with this change, where it was getting about 8 Mbps
>>>>>>>> prior to this change and ~170 Mbps prior to the reordering fix. A pcap
>>>>>>>> from the receiving system shows a very large number of out of order
>>>>>>>> frames, likely due to TCP retransmission.
>>>>>>>>
>>>>>>>> An 802.11n MacBook gets very good throughput, only the 802.11ac
>>>>>>>> MacBook shows the very poor result. I'm trying to figure out why.
>>>>>>>>
>>>>>>>>
>>>>>>>> One specific note (and probably not related to the throughput): I
>>>>>>>> believe ath10k_htt_rx_amsdu runs in the tasklet, which means it would
>>>>>>>> need to use GFP_ATOMIC instead of GFP_KERNEL. Do I understand it
>>>>>>>> correctly?
>>>>>>>>
>>>>>>>>
>>>>>>>> On Mon, Jul 7, 2014 at 1:30 AM, Janusz Dziedzic
>>>>>>>> <janusz.dziedzic at tieto.com> wrote:
>>>>>>>>> On 6 July 2014 04:27, Adrian Chadd <adrian at freebsd.org> wrote:
>>>>>>>>>> I think you may have to tell mac80211 that it's okay and not to drop the frames.
>>>>>>>>>>
>>>>>>>>>> The earlier atheros chips would just give you the AMSDU frames as
>>>>>>>>>> deaggregated A-MPDU sub-frames - you'd just pass the A-MSDU up to
>>>>>>>>>> net80211 and it'd ull it apart. But if the driver is doing it (or,
>>>>>>>>>> well, the chip is doing it) then mac80211 needs to know not to drop
>>>>>>>>>> those sub-frames.
>>>>>>>>>>
>>>>>>>>>> I wonder if you'll ever get notified before the complete A-MPDU has
>>>>>>>>>> been received. That happens on previous chips. eg, you have an A-MPDU
>>>>>>>>>> of 16 frames with 4 MSDUs in each MPDU. If you get notified and handle
>>>>>>>>>> half of one MPDU before you hit EOL, the next notification you process
>>>>>>>>>> will be the next MSDU in the same MPDU - and then you'll hit the
>>>>>>>>>> reordering hilarity again.
>>>>>>>>>>
>>>>>>>>>> So hm, i will face the same issue in FreeBSD at some point, so I'd
>>>>>>>>>> likely do what you're thinking of doing - pass up a chain of mbufs
>>>>>>>>>> representing the current MPDU and treat the whole lot as the frame(s)
>>>>>>>>>> to care about. Honestly though, I'm kind of wondering whether I should
>>>>>>>>>> mostly just do what the Atheros reference driver does and treat it as
>>>>>>>>>> ethernet payload frames (ie, it's already de-encapsulated and the
>>>>>>>>>> reordering is already done) and just tack on the wifi header bit via
>>>>>>>>>> another of the DMA rings.
>>>>>>>>>>
>>>>>>>>>> Ugh, I really should sit down and write the FreeBSD version of this.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> -a
>>>>>>>>>>
>>>>>>>>>> (I'm still having flashbacks from working on this firmware at QCA. Aiee.)
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On 5 July 2014 06:55, Denton Gentry <denton.gentry at gmail.com> wrote:
>>>>>>>>>>> There are two issues in handling the dis-aggregated A-MSDU subframes
>>>>>>>>>>> in ieee80211_sta_manage_reorder_buf:
>>>>>>>>>>>
>>>>>>>>>>> 1. The out-of-date check:
>>>>>>>>>>>
>>>>>>>>>>>         /* frame with out of date sequence number */
>>>>>>>>>>>         if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
>>>>>>>>>>>                 dev_kfree_skb(skb);
>>>>>>>>>>>                 goto out;
>>>>>>>>>>>         }
>>>>>>>>>>>
>>>>>>>>>>> As all of the subframes carry the same sequence number, the first
>>>>>>>>>>> subframe will be delivered and increment head_seq_num and then all
>>>>>>>>>>> subsequent subframes will be discarded.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> 2. The duplicates check a bit later in the routine:
>>>>>>>>>>>
>>>>>>>>>>>         /* check if we already stored this frame */
>>>>>>>>>>>         if (tid_agg_rx->reorder_buf[index]) {
>>>>>>>>>>>                 dev_kfree_skb(skb);
>>>>>>>>>>>                 goto out;
>>>>>>>>>>>         }
>>>>>>>>>>>
>>>>>>>>>>> If there is enough packet loss that packets are queued in the reorder
>>>>>>>>>>> buffer and not immediately released, then only the first subframe will
>>>>>>>>>>> be stored. Subsequent subframes will be discarded as duplicates.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> An 802.11ac MacBook is able to get about 170 Mbps with iperf prior to
>>>>>>>>>>> the reordering buffer changes, and dropped to about 8 Mbps with the
>>>>>>>>>>> reorder buffer. Hacking around the out-of-date sequence number check
>>>>>>>>>>> to allow all subframes to egress restores it to 170 Mbps.
>>>>>>>>>>>
>>>>>>>>>>> In the area where I'm testing there isn't enough 5 GHz noise to make
>>>>>>>>>>> the duplicates-check issue happen very often. By adding a printk I can
>>>>>>>>>>> see that it does happen, but it doesn't impact the throughput and I
>>>>>>>>>>> can't report the impact of fixing it.
>>>>>>>>>>>
>>>>>>>>>>> ----
>>>>>>>>>>>
>>>>>>>>>>> I do wonder if both of these are symptoms of dis-aggregating the
>>>>>>>>>>> A-MSDU too early. mac80211 expects to be dealing with the whole MPDU
>>>>>>>>>>> at a time, and the ath10k A-MSDU case is sending it subframes instead.
>>>>>>>>>>> Trying to make the ath10k code send up all of the subframes as a chain
>>>>>>>>>>> of skbs didn't immediately work, but I do wonder if that would better
>>>>>>>>>>> match the mac80211 expectations.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> On Fri, Jul 4, 2014 at 11:58 AM, Denton Gentry <denton.gentry at gmail.com> wrote:
>>>>>>>>>>>> Yes, after some more testing it does look like an unfortunate
>>>>>>>>>>>> interaction between the reorder buffer and A-MSDU. The disaggregated
>>>>>>>>>>>> subframes all carry the same sequence number. The first subframe is
>>>>>>>>>>>> released from the reorder buffer and increments the head_seq_num.
>>>>>>>>>>>> Subsequent subframes are all discarded as being out of date.
>>>>>>>>>>>>
>>>>>>>>>>>> [  308.514021] ieee80211_sta_manage_reorder_buf: out of date seq=0xb05
>>>>>>>>>>>> head=0xb06
>>>>>>>>>>>> [  308.520577] ieee80211_sta_manage_reorder_buf: out of date seq=0xb0a
>>>>>>>>>>>> head=0xb0b
>>>>>>>>>>>> [  308.527198] ieee80211_sta_manage_reorder_buf: out of date seq=0xb0f
>>>>>>>>>>>> head=0xb10
>>>>>>>>>>>> [  308.533857] ieee80211_sta_manage_reorder_buf: out of date seq=0xb14
>>>>>>>>>>>> head=0xb15
>>>>>>>>>>>> [  308.540480] ieee80211_sta_manage_reorder_buf: out of date seq=0xb19
>>>>>>>>>>>> head=0xb1a
>>>>>>>>>>>> [  308.547730] ieee80211_sta_manage_reorder_buf: out of date seq=0xb1e
>>>>>>>>>>>> head=0xb1f
>>>>>>>>>>>> [  308.554069] ieee80211_sta_manage_reorder_buf: out of date seq=0xb23
>>>>>>>>>>>> head=0xb24
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> On Wed, Jul 2, 2014 at 9:49 AM, Michal Kazior <michal.kazior at tieto.com> wrote:
>>>>>>>>>>>>> On 30 June 2014 22:15, Denton Gentry <denton.gentry at gmail.com> wrote:
>>>>>>>>>>>>>> In iperf tests using a MacBook STA bridging through an ath10k AP to an
>>>>>>>>>>>>>> Ethernet server, I'm noticing very selective packet loss. The second
>>>>>>>>>>>>>> and subsequent frames in an A-MSDU packet appear to be dropped.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> The AP sets the A-MSDU size to 3839 bytes, and the MacBook frequently
>>>>>>>>>>>>>> sends A-MSDU packets containing two TCP frames. So far as I can tell,
>>>>>>>>>>>>>> the first TCP frame from an A-MSDU aggregate is delivered and the
>>>>>>>>>>>>>> second is consistently lost. The MacBook generally retransmits the
>>>>>>>>>>>>>> lost frame as a singleton with no aggregation, and the retransmitted
>>>>>>>>>>>>>> frame makes it through.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> This became more noticeable after the reordering fixes in
>>>>>>>>>>>>>> http://lists.infradead.org/pipermail/ath10k/2014-June/002552.html
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> I see this A-MSDU packet loss behavior both with and without the
>>>>>>>>>>>>>> reordering fixes, the first packet in an A-MSDU is delivered while the
>>>>>>>>>>>>>> second is dropped. However, *without* the reordering fixes (and
>>>>>>>>>>>>>> therefore with packets delivered out of order) the MacBook sends
>>>>>>>>>>>>>> relatively few A-MSDU frames. *With* the reordering fixes, so all
>>>>>>>>>>>>>> packets are delivered in order, the MacBook keeps sending A-MSDU and
>>>>>>>>>>>>>> therefore has to deal with more packet loss. I suspect it is an
>>>>>>>>>>>>>> interaction with the MacOS TCP congestion window which I'm likely
>>>>>>>>>>>>>> never going to fully understand, its stuck in a region of the
>>>>>>>>>>>>>> congestion window where the Wifi driver keeps choosing to using
>>>>>>>>>>>>>> A-MSDU.
>>>>>>>>>>>>>
>>>>>>>>>>>>> I was actually worried about A-MSDU once A-MPDU re-ordering issue was raised.
>>>>>>>>>>>>>
>>>>>>>>>>>>> ath10k fw reports A-MSDU subframes separately. To avoid memory
>>>>>>>>>>>>> copying/allocation overhead each subframe is reported as a singly
>>>>>>>>>>>>> A-MSDU MSDU to mac80211 with an extra rx_flag AMSDU_MORE. Perhaps
>>>>>>>>>>>>> A-MPDU reordering intereferes with A-MSDU now?
>>>>>>>>>>>>>
>>>>>>>>> Denton could you try attached patch: report amsdu in one big frame.
>>>>>>>>> If help, we can add amsdu skb list support to mac80211/cfg80211 - to
>>>>>>>>> improve performance and reduce memcpy, while currently we have skb
>>>>>>>>> frames, put them in one big skb and next cfg80211 split them again
>>>>>>>>> into msdus and report to stack.
>>>>>>>>>
>>>>>>>>> BR
>>>>>>>>> Janusz



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