From the kernel log - any ideas what this means? And more importantly, is there anything to be done to avoid this issue?
[472537.739861] ------------[ cut here ]------------
[472537.739931] WARNING: CPU: 1 PID: 1520 at backports-4.19.161-1/net/wireless/util.c:1147 0xbf1e5d88 [cfg80211@bf1e1000+0x37000]
[472537.743621] invalid rate bw=0, mcs=15, nss=4
[472537.754945] Modules linked in: pppoe ppp_async ath10k_pci ath10k_core ath pppox ppp_generic nf_conntrack_ipv6 mac80211 iptable_nat ipt_REJECT ipt_MASQUERADE cfg80211 xt_time xt_tcpudp xt_state xt_nat xt_multiport xt_mark xt_mac xt_limit xt_conntrack xt_comment xt_TCPMSS xt_REDIRECT xt_LOG xt_FLOWOFFLOAD xt_CT slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_flow_table_hw nf_flow_table nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat ledtrig_usbport nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables ip6t_REJECT x_tables nf_reject_ipv6 leds_gpio xhci_plat_hcd xhci_pci xhci_hcd dwc3 dwc3_of_simple ohci_platform ohci_hcd phy_qcom_dwc3 ahci ehci_platform
[472537.808159] sd_mod ahci_platform libahci_platform libahci libata scsi_mod ehci_hcd gpio_button_hotplug
[472537.830074] CPU: 1 PID: 1520 Comm: hostapd Not tainted 4.14.215 #0
[472537.839572] Hardware name: Generic DT based system
[472537.845563] Function entered at [<c030f1c4>] from [<c030b390>]
[472537.850418] Function entered at [<c030b390>] from [<c07c2844>]
[472537.856322] Function entered at [<c07c2844>] from [<c031f91c>]
[472537.862226] Function entered at [<c031f91c>] from [<c031f97c>]
[472537.868127] Function entered at [<c031f97c>] from [<bf1e5d88>]
[472537.874077] Function entered at [<bf1e5d88>] from [<bf1f387c>]
[472537.879942] Function entered at [<bf1f387c>] from [<bf2006b8>]
[472537.885842] Function entered at [<bf2006b8>] from [<bf2010b0>]
[472537.891742] Function entered at [<bf2010b0>] from [<c06e33d4>]
[472537.897644] Function entered at [<c06e33d4>] from [<c06e1d78>]
[472537.903544] Function entered at [<c06e1d78>] from [<c06e23c8>]
[472537.909447] Function entered at [<c06e23c8>] from [<c06e1588>]
[472537.915349] Function entered at [<c06e1588>] from [<c06e19a4>]
[472537.921253] Function entered at [<c06e19a4>] from [<c068b7e8>]
[472537.927157] Function entered at [<c068b7e8>] from [<c068c050>]
[472537.933057] Function entered at [<c068c050>] from [<c0307b60>]
[472537.939097] ---[ end trace 47de6c469bac06fb ]---