wpa_supplicant 2.10 (also HEAD): mt7610 USB 5 GHz AP limited to 20 MHz, but hostapd can configure 80MHz?

Sun Apr 16 08:15:00 PDT 2023

I'm trying to use NetworkManager built-in hotspot functionality with ASUS AC51 USB.

This uses wpa_supplicant over DBus. While 5 GHz hotspot and bridge work great at setup level, for some reason, my transfers are capped at exactly 54 Mbps.

I've also tested hostapd: was able to configure it to 80 MHz, and get (exactly) 4x higher speeds, or ~220 Mbps.

What is going wrong for wpa_supplicant? Isn't it supposed to be able to autoconfigure the adapter to the max of its capabilities?

± iw dev wlp8s0f4u1 info
Interface wlp8s0f4u1
        ifindex 4
        wdev 0x1
        addr 04:42:1a:5b:ac:cf
        ssid <SSID>
        type AP
        wiphy 0
        channel 36 (5180 MHz), width: 20 MHz, center1: 5180 MHz
        txpower 19.00 dBm
        multicast TXQ:
                qsz-byt qsz-pkt flows   drops   marks   overlmt hashcol
tx-bytes        tx-packets
                0       0       2823    0       0       0       1     
901860          2860

± iw dev wlp8s0f4u1 station dump
Station <MAC> (on wlp8s0f4u1)
        inactive time:  3 ms
        rx bytes:       92819253
        rx packets:     91260
        tx bytes:       79483297
        tx packets:     58871
        tx retries:     4111
        tx failed:      9
        rx drop misc:   0
        signal:         -61 [-61] dBm
        signal avg:     -60 [-60] dBm
        tx bitrate:     86.7 MBit/s VHT-MCS 8 short GI VHT-NSS 1
        tx duration:    5422958 us
        rx bitrate:     86.7 MBit/s VHT-MCS 8 short GI VHT-NSS 1
        rx duration:    400012 us
        airtime weight: 256
        expected throughput:    37.627Mbps
        authorized:     yes
        authenticated:  yes
        associated:     yes
        preamble:       long
        WMM/WME:        yes
        MFP:            yes
        TDLS peer:      no
        DTIM period:    2
        beacon interval:100
        short slot time:yes
        connected time: 423 seconds
        associated at [boottime]:       67708.010s
        associated at:  1681639933441 ms
        current time:   1681640356245 ms

>From wpa_supplicant logs, I'm unclear on who's forcing `bandwidth=20` - is it NetworkManager, or wpa_supplicant's autoconfiguration?
Why isn't it configuring for more?

...
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: Setup AP(wlp8s0f4u1) - device_ap_sme=0 use_monitor=0
...
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: Set freq 5180 (ht_enabled=0, vht_enabled=0, he_enabled=0, eht_enabled=0, bandwidth=0 MHz, cf1=0 MHz, cf2=0 MHz)
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * freq=5180
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * eht_enabled=0
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * he_enabled=0
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * vht_enabled=0
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * ht_enabled=0
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * radar_background=0
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * channel_type=0
apr   16 15:49:41 gusto wpa_supplicant[1116946]: Determining HT/VHT options based on driver capabilities (freq=5180 chan=36)
apr   16 15:49:41 gusto wpa_supplicant[1116946]: Enable HT support (p2p_group=0 11a=1 ht40_hw_capab=1 ssid->ht40=0)
apr   16 15:49:41 gusto wpa_supplicant[1116946]: HT secondary channel offset 0 for AP
apr   16 15:49:41 gusto wpa_supplicant[1116946]: No VHT higher bandwidth support for the selected channel 36
apr   16 15:49:41 gusto wpa_supplicant[1116946]: phy: phy0
apr   16 15:49:41 gusto wpa_supplicant[1116946]: BSS count 1, BSSID mask 00:00:00:00:00:00 (0 bits)
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: Regulatory information - country=EE (DFS-ETSI)
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: 2400-2483 @ 40 MHz 20 mBm
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: 5150-5250 @ 80 MHz 23 mBm (no outdoor)
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: 5250-5350 @ 80 MHz 20 mBm (no outdoor) (DFS)
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: 5470-5725 @ 160 MHz 26 mBm (DFS)
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: 5725-5875 @ 80 MHz 13 mBm
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: 5945-6425 @ 160 MHz 23 mBm (no outdoor)
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: 57000-66000 @ 2160 MHz 40 mBm
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: Added 802.11b mode based on 802.11g information
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: Mode IEEE 802.11g: 2412 2417 2422 2427 2432 2437 2442 2447 2452 2457 2462 2467 2472 2484[DISABLED][NO_IR]
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: Mode IEEE 802.11a: 5180 5200 5220 5240 5260[RADAR] 5280[RADAR] 5300[RADAR] 5320[RADAR] 5500[RADAR] 5520[RADAR] 5540[RADAR] 5560[RADAR] 5580[RADAR] 5600[RADAR] 5620[RADAR] 5640[RAD>
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: Mode IEEE 802.11b: 2412 2417 2422 2427 2432 2437 2442 2447 2452 2457 2462 2467 2472 2484[DISABLED][NO_IR]
apr   16 15:49:41 gusto wpa_supplicant[1116946]: hw vht capab: 0x31800120, conf vht capab: 0x31800120
apr   16 15:49:41 gusto wpa_supplicant[1116946]: Completing interface initialization
apr   16 15:49:41 gusto wpa_supplicant[1116946]: Mode: IEEE 802.11a  Channel: 36  Frequency: 5180 MHz
apr   16 15:49:41 gusto wpa_supplicant[1116946]: DFS 0 channels required radar detection
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: Set freq 5180 (ht_enabled=1, vht_enabled=1, he_enabled=0, eht_enabled=0, bandwidth=20 MHz, cf1=5180 MHz, cf2=0 MHz)
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * freq=5180
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * eht_enabled=0
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * he_enabled=0
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * vht_enabled=1
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * ht_enabled=1
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * radar_background=0
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * bandwidth=20
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * channel_width=1
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * center_freq1=5180
apr   16 15:49:41 gusto wpa_supplicant[1116946]:   * center_freq2=0
apr   16 15:49:41 gusto wpa_supplicant[1116946]: RATE[0] rate=60 flags=0x1
apr   16 15:49:41 gusto wpa_supplicant[1116946]: RATE[1] rate=90 flags=0x0
apr   16 15:49:41 gusto wpa_supplicant[1116946]: RATE[2] rate=120 flags=0x1
apr   16 15:49:41 gusto wpa_supplicant[1116946]: RATE[3] rate=180 flags=0x0
apr   16 15:49:41 gusto wpa_supplicant[1116946]: RATE[4] rate=240 flags=0x1
apr   16 15:49:41 gusto wpa_supplicant[1116946]: RATE[5] rate=360 flags=0x0
apr   16 15:49:41 gusto wpa_supplicant[1116946]: RATE[6] rate=480 flags=0x0
apr   16 15:49:41 gusto wpa_supplicant[1116946]: RATE[7] rate=540 flags=0x0
apr   16 15:49:41 gusto wpa_supplicant[1116946]: hostapd_setup_bss(hapd=0x5655361dd670 (wlp8s0f4u1), first=1)
apr   16 15:49:41 gusto wpa_supplicant[1116946]: nl80211: flush -> DEL_STATION wlp8s0f4u1 (all)
...

Thoughts welcome!