WIFI 7: Connect to network unreliable (4WAY_HANDSHAKE_TIMEOUT)

[fubar-coder]

Hi,

sometimes, I am unable to connect to my WIFI 7 (6 GHz) network.

• OS: Linux cachyos-x8664 7.2.3-1-cachyos #1 SMP PREEMPT_DYNAMIC Sun, 06 Sep 2026 22:01:30 +0000 x86_64 GNU/Linux
• WIFI 7 USB Stick: Netgear Nighthawk WiFi 7 USB 3.0 Adapter
• Router: FRITZ!Box 5690 Pro
• Router version: 8.40-136125 BETA; using 8.25, I couldn't connect to the 6 GHz network at all
• mt76 driver commit hash: acf6a1d
• Firmware: mt7925u_git 2-2:1.0: WM Firmware Version: ____000000, Build Time: 20260605184805

I can see the 4WAY_HANDSHAKE_TIMEOUT in the log, but I'm uncertain why it sometimes still works (i.e. connect to my WIFI 7 network) and sometimes it doesn't at all, which is the reason why I let the router create two WIFI networks (2,4 & 5 GHz, and 6 GHz).

The WIFI 7 network I connect to is 6 GHz-only, channel 37, no MLO.

mt76-diag.txt

This is an excerpt from the log:

[14146.703017] wlan0: authenticate with XX:XX:XX:XX:XX:01 (local address=XX:XX:XX:XX:XX:02)
[14147.059123] wlan0: send auth to XX:XX:XX:XX:XX:01 (try 1/3)
[14147.119779] wlan0: authenticate with XX:XX:XX:XX:XX:01 (local address=XX:XX:XX:XX:XX:02)
[14147.119788] wlan0: send auth to XX:XX:XX:XX:XX:01 (try 1/3)
[14147.123560] wlan0: authenticated
[14147.126445] wlan0: associate with XX:XX:XX:XX:XX:01 (try 1/3)
[14147.182428] wlan0: RX AssocResp from XX:XX:XX:XX:XX:01 (capab=0x1411 status=0 aid=4)
[14147.215589] wlan0: associated
[14150.326190] wlan0: deauthenticated from XX:XX:XX:XX:XX:01 (Reason: 15=4WAY_HANDSHAKE_TIMEOUT)
[14153.506481] wlan0: authenticate with XX:XX:XX:XX:XX:01 (local address=XX:XX:XX:XX:XX:02)
[14153.525600] wlan0: send auth to XX:XX:XX:XX:XX:01 (try 1/3)
[14153.530352] wlan0: authenticated
[14153.532338] wlan0: associate with XX:XX:XX:XX:XX:01 (try 1/3)
[14153.560069] wlan0: RX AssocResp from XX:XX:XX:XX:XX:01 (capab=0x1411 status=0 aid=4)
[14153.593619] wlan0: associated
[14156.705082] wlan0: deauthenticated from XX:XX:XX:XX:XX:01 (Reason: 15=4WAY_HANDSHAKE_TIMEOUT)

This is the information about my WIFI USB stick:

Bus 002 Device 003: ID 0846:9072 NetGear, Inc. Wireless_Device
Negotiated speed: SuperSpeed (5Gbps)
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               3.20
  bDeviceClass            0 [unknown]
  bDeviceSubClass         0 [unknown]
  bDeviceProtocol         0
  bMaxPacketSize0         9
  idVendor           0x0846 NetGear, Inc.
  idProduct          0x9072 Wireless_Device
  bcdDevice            1.00
  iManufacturer           2 MediaTek Inc.
  iProduct                3 Wireless_Device
  iSerial                 4 000000000
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0087
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          5 Config_01
    bmAttributes         0xe0
      Self Powered
      Remote Wakeup
    MaxPower              160mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           9
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceProtocol    255 Vendor Specific Protocol
      iInterface              1 WiFi_If
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x84  EP 4 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst               3
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x85  EP 5 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x08  EP 8 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x04  EP 4 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst               3
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x05  EP 5 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst               3
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x06  EP 6 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst               3
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x07  EP 7 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst               3
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x09  EP 9 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst               3
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x86  EP 6 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0002  1x 2 bytes
        bInterval               1
        bMaxBurst               0
        wBytesPerInterval       2
Binary Object Store Descriptor:
  bLength                 5
  bDescriptorType        15
  wTotalLength       0x0016
  bNumDeviceCaps          2
  USB 2.0 Extension Device Capability:
    bLength                 7
    bDescriptorType        16
    bDevCapabilityType      2
    bmAttributes   0x0000f11e
      BESL Link Power Management (LPM) Supported
      Baseline BESL value    150 us
      Deep BESL value      10000 us
  SuperSpeed USB Device Capability:
    bLength                10
    bDescriptorType        16
    bDevCapabilityType      3
    bmAttributes         0x00
    wSpeedsSupported   0x000e
      Device can operate at Full Speed (12Mbps)
      Device can operate at High Speed (480Mbps)
      Device can operate at SuperSpeed (5Gbps)
    bFunctionalitySupport   1
      Lowest fully-functional device speed is Full Speed (12Mbps)
    bU1DevExitLat          10 micro seconds
    bU2DevExitLat         180 micro seconds
Device Status:     0x0001
  Self Powered

journalctl log:

Sep 10 12:12:06 cachyos-x8664 wpa_supplicant[894]: wlan0: SME: Trying to authenticate with XX:XX:XX:XX:XX:01 (SSID='wifi-7' freq=6135 MHz)
Sep 10 12:12:06 cachyos-x8664 NetworkManager[805]: <info>  [1789035126.6667] device (wlan0): supplicant interface state: scanning -> authenticating
Sep 10 12:12:06 cachyos-x8664 NetworkManager[805]: <info>  [1789035126.6667] device (p2p-dev-wlan0): supplicant management interface state: scanning -> authenticating
Sep 10 12:12:06 cachyos-x8664 wpa_supplicant[894]: wlan0: Trying to associate with XX:XX:XX:XX:XX:01 (SSID='wifi-7' freq=6135 MHz)
Sep 10 12:12:06 cachyos-x8664 NetworkManager[805]: <info>  [1789035126.6728] device (wlan0): supplicant interface state: authenticating -> associating
Sep 10 12:12:06 cachyos-x8664 NetworkManager[805]: <info>  [1789035126.6728] device (p2p-dev-wlan0): supplicant management interface state: authenticating -> associating
Sep 10 12:12:06 cachyos-x8664 wpa_supplicant[894]: wlan0: Associated with XX:XX:XX:XX:XX:01
Sep 10 12:12:06 cachyos-x8664 wpa_supplicant[894]: wlan0: CTRL-EVENT-SUBNET-STATUS-UPDATE status=0
Sep 10 12:12:06 cachyos-x8664 wpa_supplicant[894]: wlan0: CTRL-EVENT-REGDOM-CHANGE init=COUNTRY_IE type=COUNTRY alpha2=DE
Sep 10 12:12:06 cachyos-x8664 wpa_supplicant[894]: wlan0: CTRL-EVENT-REGDOM-CHANGE init=COUNTRY_IE type=COUNTRY alpha2=DE
Sep 10 12:12:06 cachyos-x8664 NetworkManager[805]: <info>  [1789035126.7461] device (wlan0): supplicant interface state: associating -> 4way_handshake
Sep 10 12:12:06 cachyos-x8664 NetworkManager[805]: <info>  [1789035126.7461] device (p2p-dev-wlan0): supplicant management interface state: associating -> 4way_handshake
Sep 10 12:12:09 cachyos-x8664 wpa_supplicant[894]: wlan0: CTRL-EVENT-DISCONNECTED bssid=XX:XX:XX:XX:XX:01 reason=15

iw reg get:

global
country DE: DFS-ETSI
        (2400 - 2483 @ 40), (N/A, 20), (N/A)
        (5150 - 5250 @ 80), (N/A, 23), (N/A), NO-OUTDOOR, AUTO-BW
        (5250 - 5350 @ 80), (N/A, 20), (0 ms), NO-OUTDOOR, DFS, AUTO-BW
        (5470 - 5725 @ 160), (N/A, 26), (0 ms), DFS
        (5725 - 5875 @ 80), (N/A, 13), (N/A)
        (5945 - 6425 @ 320), (N/A, 23), (N/A), NO-OUTDOOR
        (57000 - 66000 @ 2160), (N/A, 40), (N/A)

How may I help to diagnose this problem?

[Ashcal9669]

Hi, thank you for the detailed information.

My view on MLO with current Wi-Fi 7 USB devices is somewhat mixed. Most of these adapters are still limited by a USB 3.0 host interface, both in terms of available throughput and power delivery. Because of that, expecting three simultaneously active MLO links from a USB adapter may not be realistic, even if the underlying chipset technically supports it.

Each additional active link/radio increases the power requirement. The adapter may still associate with an MLO-capable Wi-Fi 7 BSSID, but that does not necessarily mean the USB implementation can sustain every capability provided by the chipset.

In your case, however, the more interesting part is that the adapter does successfully associate on 6 GHz and then loses the connection. Your diagnostic report also shows that the adapter is capable of operating at 6135 MHz with a 160 MHz 2×2 link, reaching approximately 2401.9 Mbit/s TX, so basic 6 GHz operation is clearly functional.

What I would investigate first is the USB power/link state. Your USB descriptor reports only:

MaxPower 160mA

For this class of Wi-Fi adapter, particularly during sustained 6 GHz operation, that value stands out. While MaxPower is the USB descriptor's declared power requirement rather than a live current measurement, the combination of successful association followed by disconnects makes insufficient or unstable USB power delivery a plausible cause.

I would therefore test the adapter on another native USB 3.x port, preferably directly connected to the motherboard rather than through a hub, extension cable, or front-panel connector. I would also verify that it remains negotiated at SuperSpeed and check for USB resets, link-state transitions, or power-management events in dmesg.

The 4WAY_HANDSHAKE_TIMEOUT may ultimately be a driver/firmware or AP interoperability issue, but I would rule out USB power delivery first given the behaviour you're seeing.