GL-MT300N-V2 crashes with OpenWrt 21.02.1

My GL-MT300N-V2 crashes occasionally every x days. It has the latest OpenWrt 21.02.1 installed.

The system log shows following at the time of reboot (I guess it is after the reboot):

Thu Jan  6 16:14:03 2022 daemon.notice hostapd: Configuration file: /var/run/hostapd-phy0.conf (phy wlan0) --> new PHY
Thu Jan  6 16:14:03 2022 kern.info kernel: [   36.146400] br-lan: port 3(wlan0) entered blocking state
Thu Jan  6 16:14:03 2022 kern.info kernel: [   36.151894] br-lan: port 3(wlan0) entered disabled state
Thu Jan  6 16:14:03 2022 kern.info kernel: [   36.157748] device wlan0 entered promiscuous mode
Thu Jan  6 16:14:03 2022 daemon.notice hostapd: wlan0: interface state UNINITIALIZED->COUNTRY_UPDATE
Thu Jan  6 16:14:03 2022 daemon.notice hostapd: ACS: Automatic channel selection started, this may take a bit
Thu Jan  6 16:14:03 2022 daemon.notice hostapd: wlan0: interface state COUNTRY_UPDATE->ACS
Thu Jan  6 16:14:03 2022 daemon.notice hostapd: wlan0: ACS-STARTED
Thu Jan  6 16:14:03 2022 daemon.notice netifd: wan (1842): udhcpc: sending discover
Thu Jan  6 16:14:06 2022 daemon.notice netifd: wan (1842): udhcpc: sending discover
Thu Jan  6 16:14:11 2022 daemon.notice hostapd: ACS: Survey is missing noise floor
Thu Jan  6 16:14:11 2022 daemon.notice hostapd: ACS: Survey is missing noise floor
Thu Jan  6 16:14:11 2022 daemon.notice hostapd: ACS: Survey is missing noise floor
Thu Jan  6 16:14:11 2022 daemon.notice hostapd: ACS: Survey is missing noise floor
...
Thu Jan  6 16:14:11 2022 daemon.notice hostapd: ACS: Survey is missing noise floor
Thu Jan  6 16:14:11 2022 daemon.notice hostapd: ACS: Survey is missing noise floor
Thu Jan  6 16:14:11 2022 daemon.notice hostapd: wlan0: ACS-COMPLETED freq=2452 channel=9
Thu Jan  6 16:14:11 2022 daemon.notice hostapd: wlan0: interface state ACS->HT_SCAN
Thu Jan  6 16:14:12 2022 daemon.notice hostapd: 20/40 MHz operation not permitted on channel pri=9 sec=13 based on overlapping BSSes
Thu Jan  6 16:14:12 2022 kern.info kernel: [   45.314990] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
Thu Jan  6 16:14:12 2022 kern.info kernel: [   45.321752] br-lan: port 3(wlan0) entered blocking state
Thu Jan  6 16:14:12 2022 kern.info kernel: [   45.327204] br-lan: port 3(wlan0) entered forwarding state
Thu Jan  6 16:14:12 2022 daemon.notice netifd: Network device 'wlan0' link is up
Thu Jan  6 16:14:12 2022 kern.info kernel: [   45.345137] br-lan: port 4(wlan0-1) entered blocking state
Thu Jan  6 16:14:12 2022 kern.info kernel: [   45.350800] br-lan: port 4(wlan0-1) entered disabled state
Thu Jan  6 16:14:12 2022 kern.info kernel: [   45.356801] device wlan0-1 entered promiscuous mode
Thu Jan  6 16:14:12 2022 kern.info kernel: [   45.368912] br-lan: port 4(wlan0-1) entered blocking state
Thu Jan  6 16:14:12 2022 kern.info kernel: [   45.374563] br-lan: port 4(wlan0-1) entered forwarding state
Thu Jan  6 16:14:13 2022 daemon.notice netifd: Network device 'wlan0-1' link is up
Thu Jan  6 16:14:13 2022 kern.info kernel: [   45.585918] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0-1: link becomes ready
Thu Jan  6 16:14:13 2022 daemon.notice hostapd: wlan0: interface state HT_SCAN->ENABLED
Thu Jan  6 16:14:13 2022 daemon.notice hostapd: wlan0: AP-ENABLED

I have an additional guest wlan. Maybe there is a problem with the wifi driver?

My wireless config is as follows:

config wifi-device 'radio0'
	option type 'mac80211'
	option hwmode '11g'
	option path 'platform/10300000.wmac'
	option country 'DE'
	option channel 'auto'
	option cell_density '0'
	option htmode 'HT40'

config wifi-iface 'default_radio0'
	option device 'radio0'
	option mode 'ap'
	option wds '1'
	option key 'xxx'
	option network 'lan'
	option ieee80211w '1'
	option ssid 'xxx'
	option encryption 'sae-mixed'
	option wpa_disable_eapol_key_retries '1'

config wifi-iface 'wifinet0'
	option device 'radio0'
	option mode 'ap'
	option network 'lan'
	option key 'xxx'
	option ieee80211w '1'
	option ssid 'xxx'
	option encryption 'sae-mixed'

Anybody an idea how to solve this?

If not, how can I get more log info from the time before a reboot to identify the root cause?