R7800 crash message

Hi,

I have a 7800 which is running Hnyman's build at the moment. I seem to have occasional issues with wireless where the 5Ghz and 2.4Ghz channels drop (Sometimes after 20 seconds or so but sometimes I need to power off and back on). The white light on the top flashes.
The deployment is certainly not clean as it has been upgraded many times starting from ddwrt to standard openwrt and then hnyman so I fully understand that I should probably wipe.
I've found what looks like a crash message in the logs. I can also see that, when this happens, the logs from the device seem to be re-uploaded to my syslog server. For example, I can see the logs for 21st, 22nd, 23rd July and then I see 21st July logs for the last reboot and then 24th July logs of a fresh reboot. I have to scroll back to the previous 21st July to see the crash message.
I've captured something similar from 27th if it is of any help.

Also as a minor question, I get loads of the below messages. This may be me buggering around with the settings though so not quite as concerned.
Jul 25 01:08:23 ROUTER odhcp6c[1547]: Failed to send DHCPV6 message to ff02::1:2 (Address not available)

Would appreciate any thoughts anyone has please.
thanks

Jul 27 13:48:44 ROUTER kernel: [253638.517677] 8<--- cut here ---
Jul 27 13:48:44 ROUTER kernel: [253638.517697] Unable to handle kernel NULL pointer dereference at virtual address 00000002
Jul 27 13:48:44 ROUTER kernel: [253638.519622] pgd = 28bd5434
Jul 27 13:48:44 ROUTER kernel: [253638.528033] [00000002] *pgd=5e97c835, *pte=00000000, *ppte=00000000
Jul 27 13:48:44 ROUTER kernel: [253638.530559] Internal error: Oops: 1 [#1] SMP ARM
Jul 27 13:48:45 ROUTER kernel: [253638.537152] Modules linked in: pppoe ppp_async ath10k_pci ath10k_core ath pptp pppox ppp_mppe ppp_generic mac80211 ipt_REJECT cfg80211 xt_time xt_tcpudp xt_tcpmss xt_statistic xt_state xt_recent xt_nat xt_multiport xt_mark xt_mac xt_limit xt_length xt_hl xt_helper xt_esp xt_ecn xt_dscp xt_conntrack xt_connmark xt_connlimit xt_connbytes xt_comment xt_TCPMSS xt_REDIRECT xt_MASQUERADE xt_LOG xt_HL xt_FLOWOFFLOAD xt_DSCP xt_CT xt_CLASSIFY wireguard slhc sch_cake nf_reject_ipv4 nf_log_ipv4 nf_flow_table_hw nf_flow_table nf_conntrack_rtcache nf_conntrack_netlink nf_conncount iptable_raw iptable_nat iptable_mangle iptable_filter ipt_ah ipt_ECN ip_tables crc_ccitt compat chaoskey fuse sch_tbf sch_ingress sch_htb sch_hfsc em_u32 cls_u32 cls_tcindex cls_route cls_matchall cls_fw cls_flow cls_basic act_skbedit act_mirred ledtrig_usbport ledtrig_heartbeat xt_set ip_set_list_set ip_set_hash_netportnet ip_set_hash_netport ip_set_hash_netnet ip_set_hash_netiface ip_set_hash_net ip_set_hash_mac
Jul 27 13:48:45 ROUTER kernel: [253638.537246]  ip_set_hash_ipportnet ip_set_hash_ipportip ip_set_hash_ipport ip_set_hash_ipmark ip_set_hash_ip ip_set_bitmap_port ip_set_bitmap_ipmac ip_set_bitmap_ip ip_set nfnetlink ip6table_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip6t_NPT nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables ip6t_REJECT x_tables nf_reject_ipv6 msdos ip_gre gre ifb ip6_udp_tunnel udp_tunnel sit tunnel4 ip_tunnel tun vfat fat hfsplus cifs nls_utf8 nls_iso8859_15 nls_iso8859_1 nls_cp850 nls_cp437 nls_cp1250 sha1_generic md5 md4 ecb des_generic libdes arc4 usb_storage leds_gpio xhci_plat_hcd xhci_pci xhci_hcd dwc3 dwc3_qcom ohci_platform ohci_hcd phy_qcom_dwc3 ahci fsl_mph_dr_of ehci_platform ehci_fsl sd_mod ahci_platform libahci_platform libahci libata scsi_mod ehci_hcd gpio_button_hotplug ext4 mbcache jbd2 exfat(C) crc32c_generic
Jul 27 13:48:45 ROUTER kernel: [253638.680719] CPU: 1 PID: 15 Comm: ksoftirqd/1 Tainted: G         C        5.4.52 #0
Jul 27 13:48:45 ROUTER kernel: [253638.702950] Hardware name: Generic DT based system
Jul 27 13:48:45 ROUTER kernel: [253638.710469] PC is at ath10k_mac_tx_push_txq+0x24/0x350 [ath10k_core]
Jul 27 13:48:45 ROUTER kernel: [253638.715297] LR is at ath10k_mac_op_wake_tx_queue+0xcc/0xd8 [ath10k_core]
Jul 27 13:48:45 ROUTER kernel: [253638.721872] pc : [<bf75d4e8>]    lr : [<bf75d9d8>]    psr: 60000013
Jul 27 13:48:45 ROUTER kernel: [253638.728643] sp : dd479aa0  ip : 00000002  fp : dbf90cd8
Jul 27 13:48:45 ROUTER kernel: [253638.735065] r10: dbf90ce4  r9 : dbf90cdc  r8 : db2cc658
Jul 27 13:48:45 ROUTER kernel: [253638.740360] r7 : dc8860a4  r6 : dbf91ea0  r5 : dbf90c40  r4 : 00000002
Jul 27 13:48:45 ROUTER kernel: [253638.745658] r3 : dbf92ea0  r2 : 00000000  r1 : 00000002  r0 : dbf90c40
Jul 27 13:48:45 ROUTER kernel: [253638.751996] Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Jul 27 13:48:45 ROUTER kernel: [253638.758592] Control: 10c5787d  Table: 5e12006a  DAC: 00000051
Jul 27 13:48:45 ROUTER kernel: [253638.765885] Process ksoftirqd/1 (pid: 15, stack limit = 0xf6ec3f01)
Jul 27 13:48:45 ROUTER kernel: [253638.771699] Stack: (0xdd479aa0 to 0xdd47a000)
Jul 27 13:48:45 ROUTER kernel: [253638.778218] 9aa0: 00000000 dbf91ea0 dbf92f20 dbf90c40 dc8860a4 dbf90c40 00000002 dc8860a4
Jul 27 13:48:45 ROUTER kernel: [253638.782476] 9ac0: dc8860a4 db2cc658 dbf90cdc dbf90ce4 dbf90cd8 bf75d9d8 dbf90c40 00000000

That part is about missing realtime clock...
Time resets to last file on /etc on reboot.
Or actually it first resets to the build date/time, and then quickly fixes for the mote recent file in /etc. After network connectivity has been obtained, the time is fully updated via ntp from internet.

So, after a reboot there is always a jump in log time, as the router first reverts to 21st in the most recent reboot.

Ah ok that was a gap in my knowledge, thank you.

I didn't post in your thread as I thought it was likely a general issue with the crashing.
cheers

I've had another crash. Same as last time. This is with SNAPSHOT r13967

Aug  4 12:40:11 ROUTER kernel: [505408.580532] 8<--- cut here ---
Aug  4 12:40:11 ROUTER kernel: [505408.580563] Unable to handle kernel NULL pointer dereference at virtual address 00000864
Aug  4 12:40:11 ROUTER kernel: [505408.582494] pgd = 69d66817
Aug  4 12:40:11 ROUTER kernel: [505408.590902] [00000864] *pgd=00000000
Aug  4 12:40:12 ROUTER kernel: [505408.593429] Internal error: Oops: 17 [#1] SMP ARM
Aug  4 12:40:12 ROUTER kernel: [505408.597232] Modules linked in: pppoe ppp_async ath10k_pci ath10k_core ath pptp pppox ppp_mppe ppp_generic mac80211 ipt_REJECT cfg80211 xt_time xt_tcpudp xt_tcpmss xt_statistic xt_state xt_recent xt_nat xt_multiport xt_mark xt_mac xt_limit xt_length xt_hl xt_helper xt_esp xt_ecn xt_dscp xt_conntrack xt_connmark xt_connlimit xt_connbytes xt_comment xt_TCPMSS xt_REDIRECT xt_MASQUERADE xt_LOG xt_HL xt_FLOWOFFLOAD xt_DSCP xt_CT xt_CLASSIFY wireguard slhc sch_cake nf_reject_ipv4 nf_log_ipv4 nf_flow_table_hw nf_flow_table nf_conntrack_rtcache nf_conntrack_netlink nf_conncount iptable_raw iptable_nat iptable_mangle iptable_filter ipt_ah ipt_ECN ip_tables crc_ccitt compat chaoskey fuse sch_tbf sch_ingress sch_htb sch_hfsc em_u32 cls_u32 cls_tcindex cls_route cls_matchall cls_fw cls_flow cls_basic act_skbedit act_mirred ledtrig_usbport ledtrig_heartbeat xt_set ip_set_list_set ip_set_hash_netportnet ip_set_hash_netport ip_set_hash_netnet ip_set_hash_netiface ip_set_hash_net ip_set_hash_mac
Aug  4 12:40:12 ROUTER kernel: [505408.597331]  ip_set_hash_ipportnet ip_set_hash_ipportip ip_set_hash_ipport ip_set_hash_ipmark ip_set_hash_ip ip_set_bitmap_port ip_set_bitmap_ipmac ip_set_bitmap_ip ip_set nfnetlink ip6table_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip6t_NPT nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables ip6t_REJECT x_tables nf_reject_ipv6 msdos ip_gre gre ifb ip6_udp_tunnel udp_tunnel sit tunnel4 ip_tunnel tun vfat fat hfsplus cifs nls_utf8 nls_iso8859_15 nls_iso8859_1 nls_cp850 nls_cp437 nls_cp1250 sha1_generic md5 md4 ecb des_generic libdes arc4 usb_storage leds_gpio xhci_plat_hcd xhci_pci xhci_hcd dwc3 dwc3_qcom ohci_platform ohci_hcd phy_qcom_dwc3 ahci fsl_mph_dr_of ehci_platform ehci_fsl sd_mod ahci_platform libahci_platform libahci libata scsi_mod ehci_hcd gpio_button_hotplug ext4 mbcache jbd2 exfat(C) crc32c_generic
Aug  4 12:40:12 ROUTER kernel: [505408.740978] CPU: 0 PID: 9 Comm: ksoftirqd/0 Tainted: G         C        5.4.52 #0
Aug  4 12:40:12 ROUTER kernel: [505408.763209] Hardware name: Generic DT based system
Aug  4 12:40:12 ROUTER kernel: [505408.770749] PC is at ieee80211_tx_dequeue+0xcc/0xc28 [mac80211]
Aug  4 12:40:12 ROUTER kernel: [505408.775479] LR is at ieee80211_tx_dequeue+0x9c/0xc28 [mac80211]
Aug  4 12:40:12 ROUTER kernel: [505408.781698] pc : [<bf6b05dc>]    lr : [<bf6b05ac>]    psr: 60000013
Aug  4 12:40:12 ROUTER kernel: [505408.787686] sp : dd465a18  ip : 00001388  fp : d7fc00a4
Aug  4 12:40:12 ROUTER kernel: [505408.794020] r10: d7fc0000  r9 : 00000000  r8 : db4f0c20
Aug  4 12:40:12 ROUTER kernel: [505408.799317] r7 : db4f27e0  r6 : 00000000  r5 : 00000001  r4 : d7fc00a4
Aug  4 12:40:12 ROUTER kernel: [505408.804614] r3 : 00000702  r2 : 00000700  r1 : 00000000  r0 : db4f0ccc
Aug  4 12:40:12 ROUTER kernel: [505408.810952] Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Aug  4 12:40:12 ROUTER kernel: [505408.817549] Control: 10c5787d  Table: 5e11406a  DAC: 00000051
Aug  4 12:40:12 ROUTER kernel: [505408.824840] Process ksoftirqd/0 (pid: 9, stack limit = 0xb62e06c1)
Aug  4 12:40:12 ROUTER kernel: [505408.830655] Stack: (0xdd465a18 to 0xdd466000)
Aug  4 12:40:12 ROUTER kernel: [505408.836820] 5a00:                                                       00000000 00000000

It happens much more often when the router is busy (e.g. I'm downloading ~1TB at the moment and have had 3 crashes in 4 hours

Based on the PC's from your crash reports above my WAG is this (this patch is not currently in openwrt). Unfortunately, I really don't know so you may have to make a bug report to get someone knowledgeable to have a look if no one else responds here in the forums.

FWIW there are a lot of changes happening in "master" right now around mac82011 so I'm not surprised if its buggy ATM.

HTH

1 Like

Thank you very much for replying.
I can't say I understood everything but having browsed the 22 pages of bugs I think it probably best that I try a wipe and re-install first. Just to make sure I'm not the cause as there don't seem to be others with my issue.

1 Like

Looks like this may be related.
https://bugs.openwrt.org/index.php?do=details&task_id=2884
or maybe
https://bugs.openwrt.org/index.php?do=details&task_id=39

Either way I should still wipe. Now to find the time and patience..

And just for fun. I can make the router reboot just by trying to connect using Edge to LUCI.
I figure this is definitely something I've buggered up in the build.

Just reset to factory settings and still the same :frowning:
Not sure what else to do.

This is the last bit of the log that was exported before it was rest.

Aug 13 18:15:37 ROUTER kernel: [   40.269569] 8<--- cut here ---
Aug 13 18:15:37 ROUTER kernel: [   40.269589] Unable to handle kernel NULL pointer dereference at virtual address 00000000
Aug 13 18:15:37 ROUTER kernel: [   40.271523] pgd = e8802836
Aug 13 18:15:37 ROUTER kernel: [   40.279852] [00000000] *pgd=00000000
Aug 13 18:15:38 ROUTER kernel: [   40.282286] Internal error: Oops: 5 [#1] SMP ARM
Aug 13 18:15:38 ROUTER kernel: [   40.286004] Modules linked in: pppoe ppp_async ath10k_pci ath10k_core ath pptp pppox ppp_mppe ppp_generic mac80211 ipt_REJECT cfg80211 xt_time xt_tcpudp xt_tcpmss xt_statistic xt_state xt_recent xt_nat xt_multiport xt_mark xt_mac xt_limit xt_length xt_hl xt_helper xt_esp xt_ecn xt_dscp xt_conntrack xt_connmark xt_connlimit xt_connbytes xt_comment xt_TCPMSS xt_REDIRECT xt_MASQUERADE xt_LOG xt_HL xt_FLOWOFFLOAD xt_DSCP xt_CT xt_CLASSIFY wireguard slhc sch_cake nf_reject_ipv4 nf_log_ipv4 nf_flow_table_hw nf_flow_table nf_conntrack_rtcache nf_conntrack_netlink nf_conncount iptable_raw iptable_nat iptable_mangle iptable_filter ipt_ah ipt_ECN ip_tables exfat crc_ccitt compat chaoskey fuse sch_tbf sch_ingress sch_htb sch_hfsc em_u32 cls_u32 cls_tcindex cls_route cls_matchall cls_fw cls_flow cls_basic act_skbedit act_mirred ledtrig_usbport ledtrig_heartbeat xt_set ip_set_list_set ip_set_hash_netportnet ip_set_hash_netport ip_set_hash_netnet ip_set_hash_netiface ip_set_hash_net ip_set_hash_mac
Aug 13 18:15:38 ROUTER kernel: [   40.286112]  ip_set_hash_ipportnet ip_set_hash_ipportip ip_set_hash_ipport ip_set_hash_ipmark ip_set_hash_ip ip_set_bitmap_port ip_set_bitmap_ipmac ip_set_bitmap_ip ip_set nfnetlink ip6table_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip6t_NPT nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables ip6t_REJECT x_tables nf_reject_ipv6 msdos ip_gre gre ifb ip6_udp_tunnel udp_tunnel sit tunnel4 ip_tunnel tun vfat fat hfsplus cifs nls_utf8 nls_iso8859_15 nls_iso8859_1 nls_cp850 nls_cp437 nls_cp1250 sha1_generic md5 md4 ecb des_generic libdes arc4 usb_storage leds_gpio xhci_plat_hcd xhci_pci xhci_hcd dwc3 dwc3_qcom ohci_platform ohci_hcd phy_qcom_ipq806x_usb ahci fsl_mph_dr_of ehci_platform ehci_fsl sd_mod ahci_platform libahci_platform libahci libata scsi_mod ehci_hcd gpio_button_hotplug ext4 mbcache jbd2 crc32c_generic
Aug 13 18:15:38 ROUTER kernel: [   40.429577] CPU: 0 PID: 2423 Comm: sh Not tainted 5.4.52 #0
Aug 13 18:15:38 ROUTER kernel: [   40.451806] Hardware name: Generic DT based system
Aug 13 18:15:38 ROUTER kernel: [   40.457281] PC is at mem_cgroup_uncharge_list+0x54/0x88
Aug 13 18:15:38 ROUTER kernel: [   40.462134] LR is at mem_cgroup_uncharge_list+0x5c/0x88
Aug 13 18:15:38 ROUTER kernel: [   40.467257] pc : [<c044ef30>]    lr : [<c044ef38>]    psr: a0000013
Aug 13 18:15:38 ROUTER kernel: [   40.472462] sp : daeb1cf8  ip : 00000001  fp : 000000f1
Aug 13 18:15:38 ROUTER kernel: [   40.478713] r10: daf483cc  r9 : c0c2f640  r8 : c099528c
Aug 13 18:15:38 ROUTER kernel: [   40.483920] r7 : 00000000  r6 : 00000009  r5 : 00000000  r4 : daeb1d40
Aug 13 18:15:38 ROUTER kernel: [   40.489132] r3 : 00000000  r2 : ffffffff  r1 : daeb1cf8  r0 : 00000000
Aug 13 18:15:38 ROUTER kernel: [   40.495731] Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Aug 13 18:15:38 ROUTER kernel: [   40.502244] Control: 10c5787d  Table: 5cec006a  DAC: 00000051
Aug 13 18:15:38 ROUTER kernel: [   40.509446] Process sh (pid: 2423, stack limit = 0x439cc25a)
Aug 13 18:15:38 ROUTER kernel: [   40.515174] Stack: (0xdaeb1cf8 to 0xdaeb2000)
Aug 13 18:15:38 ROUTER kernel: [   40.520901] 1ce0:                                                       dd411000 00000001
Aug 13 18:15:38 ROUTER kernel: [   40.525172] 1d00: 00000001 00000000 00000000 00000000 00000000 ddd58710 ddd58710 ddd8a1e0
Aug 13 18:15:38 ROUTER kernel: [   40.533331] 1d20: 000000f1 c03fb638 daeb1e0c 60000013 00000001 dd406600 00000002 c0c2f640
Aug 13 18:15:38 ROUTER kernel: [   40.541489] 1d40: ddd8a1e4 ddd7a23c daeb1e0c daf48000 00000000 daeb1e0c daeb1e24 dadd1200
Aug 13 18:15:38 ROUTER kernel: [   40.549649] 1d60: daf694e0 00000001 dafe0480 c0425258 dadd1200 daeb1e0c 000000fd ffffffff
Aug 13 18:15:38 ROUTER kernel: [   40.557811] 1d80: dadd1200 c0425580 c0c5b564 00000100 20000013 c040c000 daeb1e0c c041ae50
Aug 13 18:15:38 ROUTER kernel: [   40.565971] 1da0: dae95ab4 00002000 c0c5b54c c0c07d84 dae95f60 dae95d20 00000000 becca000
Aug 13 18:15:38 ROUTER kernel: [   40.574127] 1dc0: daeb1e0c 00002000 00000000 00000001 dafe0480 c041b044 00000000 c041c654
Aug 13 18:15:38 ROUTER kernel: [   40.582286] 1de0: 00000000 dadbdf00 dadd1200 dadbdf00 00000000 db34be00 daebac00 c0423070
Aug 13 18:15:38 ROUTER kernel: [   40.590447] 1e00: 00000000 dd1e5638 db34be00 dadd1200 ffffffff ffffffff daebad81 00000001
Aug 13 18:15:38 ROUTER kernel: [   40.598607] 1e20: daf48000 daf48000 00000000 00000008 dddba318 dddbb098 dddbb0bc dddbb0e0
Aug 13 18:15:38 ROUTER kernel: [   40.606773] 1e40: dddbb104 dddbb128 dddbb14c dddbb170 dadd1200 dadd1200 00000000 c031a99c
Aug 13 18:15:38 ROUTER kernel: [   40.614925] 1e60: dadd1200 daf69080 db34be00 c045dd78 000000c0 daee8a80 c0c04e48 db34be00
Aug 13 18:15:38 ROUTER kernel: [   40.623088] 1e80: dbeea000 00000007 00000034 00000001 dafe0480 c04b2a94 00002017 00000000
Aug 13 18:15:38 ROUTER kernel: [   40.631246] 1ea0: db5ae6c0 daee8ab4 00002017 daeb1f24 00000000 d9923564 00000000 c0310d7c
Aug 13 18:15:38 ROUTER kernel: [   40.639405] 1ec0: d9923564 00000004 ddd598ec befff564 00000000 d9923564 00000004 00000000
Aug 13 18:15:38 ROUTER kernel: [   40.647562] 1ee0: 00000034 00000000 00000011 daeb1f24 00000000 00000000 fffff000 30f51eb8
Aug 13 18:15:38 ROUTER kernel: [   40.655724] 1f00: befff000 c0c148d0 db34be00 c0c5c834 fffffff8 c0c1433c c0c5c834 c0997990
Aug 13 18:15:38 ROUTER kernel: [   40.663887] 1f20: 00000002 c045cf64 daf38000 daf69080 ffffe000 00000977 daf38000 db34be00
Aug 13 18:15:38 ROUTER kernel: [   40.672047] 1f40: 00000000 dae95f00 00000001 c045d678 c0c05184 daebac00 daebac40 00000000
Aug 13 18:15:38 ROUTER kernel: [   40.680207] 1f60: daeb0000 00000000 00000000 0036aab0 0036c724 00067166 0000000b c0301204
Aug 13 18:15:38 ROUTER kernel: [   40.688368] 1f80: daeb0000 0000000b 00000000 c045e288 00000000 db355780 0004c538 0036c91c
Aug 13 18:15:38 ROUTER kernel: [   40.696523] 1fa0: 0036aab0 c0301000 0036c91c 0036aab0 0036c91c 0036aab0 0036c724 00000000
Aug 13 18:15:38 ROUTER kernel: [   40.704683] 1fc0: 0036c91c 0036aab0 00067166 0000000b 0036c724 0036c91c 00085714 00000000
Aug 13 18:15:38 ROUTER kernel: [   40.712847] 1fe0: 00084b60 bece9764 000408f4 b6f891d4 60000010 0036c91c 00000000 00000000
Aug 13 18:15:38 ROUTER kernel: [   40.721017] [<c044ef30>] (mem_cgroup_uncharge_list) from [<c03fb638>] (release_pages+0x2cc/0x358)
Aug 13 18:15:38 ROUTER kernel: [   40.729167] [<c03fb638>] (release_pages) from [<c0425258>] (tlb_batch_pages_flush+0x48/0x70)
Aug 13 18:15:38 ROUTER kernel: [   40.738026] [<c0425258>] (tlb_batch_pages_flush) from [<c0425580>] (tlb_finish_mmu+0xe0/0x174)
Aug 13 18:15:38 ROUTER kernel: [   40.746519] [<c0425580>] (tlb_finish_mmu) from [<c0423070>] (exit_mmap+0xdc/0x154)
Aug 13 18:15:38 ROUTER kernel: [   40.754947] [<c0423070>] (exit_mmap) from [<c031a99c>] (mmput+0x58/0x118)
Aug 13 18:15:38 ROUTER kernel: [   40.762502] [<c031a99c>] (mmput) from [<c045dd78>] (flush_old_exec+0x4e8/0x6e0)
Aug 13 18:15:38 ROUTER kernel: [   40.769356] [<c045dd78>] (flush_old_exec) from [<c04b2a94>] (load_elf_binary+0x660/0x1434)
Aug 13 18:15:38 ROUTER kernel: [   40.776474] [<c04b2a94>] (load_elf_binary) from [<c045cf64>] (search_binary_handler.part.3+0xa8/0x234)
Aug 13 18:15:38 ROUTER kernel: [   40.784807] [<c045cf64>] (search_binary_handler.part.3) from [<c045d678>] (__do_execve_file+0x570/0x788)
Aug 13 18:15:38 ROUTER kernel: [   40.794092] [<c045d678>] (__do_execve_file) from [<c045e288>] (sys_execve+0x38/0x48)
Aug 13 18:15:38 ROUTER kernel: [   40.803724] [<c045e288>] (sys_execve) from [<c0301000>] (ret_fast_syscall+0x0/0x54)
Aug 13 18:15:38 ROUTER kernel: [   40.811446] Exception stack(0xdaeb1fa8 to 0xdaeb1ff0)
Aug 13 18:15:38 ROUTER kernel: [   40.818827] 1fa0:                   0036c91c 0036aab0 0036c91c 0036aab0 0036c724 00000000
Aug 13 18:15:38 ROUTER kernel: [   40.824042] 1fc0: 0036c91c 0036aab0 00067166 0000000b 0036c724 0036c91c 00085714 00000000
Aug 13 18:15:38 ROUTER kernel: [   40.832196] 1fe0: 00084b60 bece9764 000408f4 b6f891d4
Aug 13 18:15:38 ROUTER kernel: [   40.840356] Code: e1cd21f0 e1cd21f8 e1a00005 e1a0100d (e4105004)
Aug 13 18:15:38 ROUTER kernel: [   40.845497] ---[ end trace 08b9b5c7f6a4975f ]---

Might be better info here:
Not sure how to read this to be fair, sorry.

Aug 20 15:03:12 ROUTER kernel: [   39.998821] 8<--- cut here ---
Aug 20 15:03:12 ROUTER kernel: [   39.998841] Unable to handle kernel NULL pointer dereference at virtual address 00000000
Aug 20 15:03:12 ROUTER kernel: [   40.000763] pgd = 3100b9dd
Aug 20 15:03:12 ROUTER kernel: [   40.009074] [00000000] *pgd=00000000
Aug 20 15:03:12 ROUTER kernel: [   40.011524] Internal error: Oops: 17 [#1] SMP ARM
Aug 20 15:03:12 ROUTER kernel: [   40.015254] Modules linked in: pppoe ppp_async ath10k_pci ath10k_core ath pptp pppox ppp_mppe ppp_generic mac80211 ipt_REJECT cfg80211 xt_time xt_tcpudp xt_tcpmss xt_statistic xt_state xt_recent xt_nat xt_multiport xt_mark xt_mac xt_limit xt_length xt_hl xt_helper xt_esp xt_ecn xt_dscp xt_conntrack xt_connmark xt_connlimit xt_connbytes xt_comment xt_TCPMSS xt_REDIRECT xt_MASQUERADE xt_LOG xt_HL xt_FLOWOFFLOAD xt_DSCP xt_CT xt_CLASSIFY wireguard slhc sch_cake nf_reject_ipv4 nf_log_ipv4 nf_flow_table_hw nf_flow_table nf_conntrack_rtcache nf_conntrack_netlink nf_conncount iptable_raw iptable_nat iptable_mangle iptable_filter ipt_ah ipt_ECN ip_tables exfat crc_ccitt compat chaoskey fuse sch_tbf sch_ingress sch_htb sch_hfsc em_u32 cls_u32 cls_tcindex cls_route cls_matchall cls_fw cls_flow cls_basic act_skbedit act_mirred ledtrig_usbport ledtrig_heartbeat xt_set ip_set_list_set ip_set_hash_netportnet ip_set_hash_netport ip_set_hash_netnet ip_set_hash_netiface ip_set_hash_net ip_set_hash_mac
Aug 20 15:03:12 ROUTER kernel: [   40.015347]  ip_set_hash_ipportnet ip_set_hash_ipportip ip_set_hash_ipport ip_set_hash_ipmark ip_set_hash_ip ip_set_bitmap_port ip_set_bitmap_ipmac ip_set_bitmap_ip ip_set nfnetlink ip6table_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip6t_NPT nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables ip6t_REJECT x_tables nf_reject_ipv6 msdos ip_gre gre ifb ip6_udp_tunnel udp_tunnel sit tunnel4 ip_tunnel tun vfat fat hfsplus cifs nls_utf8 nls_iso8859_15 nls_iso8859_1 nls_cp850 nls_cp437 nls_cp1250 sha1_generic md5 md4 ecb des_generic libdes arc4 usb_storage leds_gpio xhci_plat_hcd xhci_pci xhci_hcd dwc3 dwc3_qcom ohci_platform ohci_hcd phy_qcom_ipq806x_usb ahci fsl_mph_dr_of ehci_platform ehci_fsl sd_mod ahci_platform libahci_platform libahci libata scsi_mod ehci_hcd gpio_button_hotplug ext4 mbcache jbd2 crc32c_generic
Aug 20 15:03:12 ROUTER kernel: [   40.158909] CPU: 0 PID: 1756 Comm: sh Not tainted 5.4.52 #0
Aug 20 15:03:12 ROUTER kernel: [   40.181139] Hardware name: Generic DT based system
Aug 20 15:03:12 ROUTER kernel: [   40.186619] PC is at mem_cgroup_uncharge_list+0x54/0x88
Aug 20 15:03:12 ROUTER kernel: [   40.191470] LR is at mem_cgroup_uncharge_list+0x5c/0x88
Aug 20 15:03:12 ROUTER kernel: [   40.196592] pc : [<c044ef30>]    lr : [<c044ef38>]    psr: a0000013
Aug 20 15:03:12 ROUTER kernel: [   40.201799] sp : daeb3df8  ip : 00000001  fp : 000000f3
Aug 20 15:03:12 ROUTER kernel: [   40.208048] r10: daed53d4  r9 : c0c2f640  r8 : c099528c
Aug 20 15:03:12 ROUTER kernel: [   40.213257] r7 : 00000000  r6 : 0000000c  r5 : 00000000  r4 : daeb3e40
Aug 20 15:03:12 ROUTER kernel: [   40.218467] r3 : 00000000  r2 : 00000000  r1 : daeb3df8  r0 : 00000000
Aug 20 15:03:12 ROUTER kernel: [   40.225065] Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Aug 20 15:03:12 ROUTER kernel: [   40.231576] Control: 10c5787d  Table: 5d36806a  DAC: 00000051
Aug 20 15:03:12 ROUTER kernel: [   40.238779] Process sh (pid: 1756, stack limit = 0x4fa97387)
Aug 20 15:03:12 ROUTER kernel: [   40.244509] Stack: (0xdaeb3df8 to 0xdaeb4000)
Aug 20 15:03:12 ROUTER kernel: [   40.250238] 3de0:                                                       00000000 00000000
Aug 20 15:03:12 ROUTER kernel: [   40.254504] 3e00: 00000000 00000000 00000000 00000000 00000000 00000000 ddd59c04 ddd926a0
Aug 20 15:03:12 ROUTER kernel: [   40.262664] 3e20: 000000f3 c03fb638 daeb3f0c 60000013 00000001 dd406600 00000002 c0c2f640
Aug 20 15:03:12 ROUTER kernel: [   40.270824] 3e40: ddd926a4 ddd59860 daeb3f0c daed5000 00000000 daeb3f0c daeb3f24 c0301204
Aug 20 15:03:12 ROUTER kernel: [   40.278984] 3e60: 00000000 000000f8 00000000 c0425258 daefb600 daeb3f0c 0000007d ffffffff
Aug 20 15:03:12 ROUTER kernel: [   40.287144] 3e80: c0301204 c0425580 c0c5b564 00000100 20000013 c040c000 daeb3f0c c041ae50
Aug 20 15:03:12 ROUTER kernel: [   40.295303] 3ea0: dc213094 00002000 c0c5b54c c0c07d84 dc213120 dc213ae0 00000000 bed14000
Aug 20 15:03:12 ROUTER kernel: [   40.303463] 3ec0: daeb3f0c 00002000 00000000 000000f8 00000000 c041b044 00000000 c041c654
Aug 20 15:03:12 ROUTER kernel: [   40.311622] 3ee0: 00000000 dc213c00 daefb600 dc213c00 00000000 ffffe000 daefb640 c0423070
Aug 20 15:03:12 ROUTER kernel: [   40.319781] 3f00: 00000004 00000000 000001ff daefb600 ffffffff ffffffff dc9fbc01 00000001
Aug 20 15:03:12 ROUTER kernel: [   40.327942] 3f20: daed5000 daed5000 00000000 00000008 dd9c54a0 dddbb2b4 dddbb2d8 dddbb2fc
Aug 20 15:03:12 ROUTER kernel: [   40.336100] 3f40: dddbb320 dddbb344 dddbb368 dddbb38c c0301204 daefb600 00000000 c031a99c
Aug 20 15:03:12 ROUTER kernel: [   40.344260] 3f60: daf69080 daefb600 ffffe000 c03217d0 00000000 b6f140a0 000001ff 000000f8
Aug 20 15:03:12 ROUTER kernel: [   40.352421] 3f80: 00000000 c0321f28 00000000 bed33d58 000859ad 000000f8 c0301204 c0321fc8
Aug 20 15:03:12 ROUTER kernel: [   40.360580] 3fa0: 00000000 c0301000 00000000 bed33d58 00000000 00000000 00085960 00000000
Aug 20 15:03:12 ROUTER kernel: [   40.368739] 3fc0: 00000000 bed33d58 000859ad 000000f8 000859ad 00000000 00000020 00000000
Aug 20 15:03:12 ROUTER kernel: [   40.376899] 3fe0: 00084bb4 bed339b8 b6ef1d98 b6ebe438 60000010 00000000 00000000 00000000
Aug 20 15:03:12 ROUTER kernel: [   40.385066] [<c044ef30>] (mem_cgroup_uncharge_list) from [<c03fb638>] (release_pages+0x2cc/0x358)
Aug 20 15:03:12 ROUTER kernel: [   40.393218] [<c03fb638>] (release_pages) from [<c0425258>] (tlb_batch_pages_flush+0x48/0x70)
Aug 20 15:03:12 ROUTER kernel: [   40.402066] [<c0425258>] (tlb_batch_pages_flush) from [<c0425580>] (tlb_finish_mmu+0xe0/0x174)
Aug 20 15:03:12 ROUTER kernel: [   40.410574] [<c0425580>] (tlb_finish_mmu) from [<c0423070>] (exit_mmap+0xdc/0x154)
Aug 20 15:03:12 ROUTER kernel: [   40.418998] [<c0423070>] (exit_mmap) from [<c031a99c>] (mmput+0x58/0x118)
Aug 20 15:03:12 ROUTER kernel: [   40.426544] [<c031a99c>] (mmput) from [<c03217d0>] (do_exit+0x34c/0xa28)
Aug 20 15:03:12 ROUTER kernel: [   40.433400] [<c03217d0>] (do_exit) from [<c0321f28>] (do_group_exit+0x48/0xd4)
Aug 20 15:03:12 ROUTER kernel: [   40.440172] [<c0321f28>] (do_group_exit) from [<c0321fc8>] (__wake_up_parent+0x0/0x18)
Aug 20 15:03:12 ROUTER kernel: [   40.447210] Code: e1cd21f0 e1cd21f8 e1a00005 e1a0100d (e4105004)
Aug 20 15:03:12 ROUTER kernel: [   40.455215] ---[ end trace cca93db4284c33e3 ]---
Aug 20 15:03:12 ROUTER kernel: [   40.461261] Kernel panic - not syncing: Fatal exception
Aug 20 15:03:10 ROUTER logread[664]: Logread connected to 10.10.10.253:514
Aug 20 15:03:10 ROUTER kernel: [   42.073220] blk_update_request: I/O error, dev mtdblock0, sector 16 op 0x0:(READ) flags 0x80700 phys_seg 2 prio class 0
Aug 20 15:03:10 ROUTER kernel: [   42.084128] blk_update_request: I/O error, dev mtdblock0, sector 24 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
Aug 20 15:03:10 ROUTER kernel: [   42.094703] blk_update_request: I/O error, dev mtdblock0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0
Aug 20 15:03:10 ROUTER kernel: [   42.104527] Buffer I/O error on dev mtdblock0, logical block 0, async page read
Aug 20 15:03:10 ROUTER netifd: Interface 'wan' is now up
Aug 20 15:03:10 ROUTER kernel: [   42.133202] blk_update_request: I/O error, dev mtdblock0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0
Aug 20 15:03:10 ROUTER kernel: [   42.133234] Buffer I/O error on dev mtdblock0, logical block 0, async page read
Aug 20 15:03:10 ROUTER kernel: [   42.146047] blk_update_request: I/O error, dev mtdblock1, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 4 prio class 0
Aug 20 15:03:10 ROUTER kernel: [   42.155140] blk_update_request: I/O error, dev mtdblock1, sector 8 op 0x0:(READ) flags 0x80700 phys_seg 3 prio class 0
Aug 20 15:03:10 ROUTER kernel: [   42.161398] blk_update_request: I/O error, dev mtdblock1, sector 16 op 0x0:(READ) flags 0x80700 phys_seg 2 prio class 0
Aug 20 15:03:10 ROUTER kernel: [   42.172160] blk_update_request: I/O error, dev mtdblock1, sector 24 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
Aug 20 15:03:10 ROUTER kernel: [   42.188087] Buffer I/O error on dev mtdblock1, logical block 0, async page read
Aug 20 15:03:10 ROUTER kernel: [   42.196018] Buffer I/O error on dev mtdblock1, logical block 0, async page read
Aug 20 15:03:10 ROUTER block: No "mount.ubi" utility available
Aug 20 15:03:10 ROUTER block: mounting /dev/mtdblock6 (ubi) as /mnt/mtdblock6 failed (25) - Not a tty
Aug 20 15:03:10 ROUTER kernel: [   42.453959] ath: EEPROM regdomain: 0x833a
Aug 20 15:03:10 ROUTER kernel: [   42.453978] ath: EEPROM indicates we should expect a country code
Aug 20 15:03:10 ROUTER kernel: [   42.456939] ath: doing EEPROM country->regdmn map search
Aug 20 15:03:10 ROUTER kernel: [   42.463097] ath: country maps to regdmn code: 0x37
Aug 20 15:03:10 ROUTER kernel: [   42.468394] ath: Country alpha2 being used: GB
Aug 20 15:03:10 ROUTER kernel: [   42.473057] ath: Regpair used: 0x37
Aug 20 15:03:10 ROUTER kernel: [   42.477429] ath: regdomain 0x833a dynamically updated by user
Aug 20 15:03:10 ROUTER kernel: [   42.480830] ath: EEPROM regdomain: 0x833a
Aug 20 15:03:10 ROUTER kernel: [   42.486792] ath: EEPROM indicates we should expect a country code
Aug 20 15:03:10 ROUTER kernel: [   42.490709] ath: doing EEPROM country->regdmn map search
Aug 20 15:03:10 ROUTER kernel: [   42.496864] ath: country maps to regdmn code: 0x37
Aug 20 15:03:10 ROUTER odhcp6c[1117]: Failed to send DHCPV6 message to ff02::1:2 (Address not available)
Aug 20 15:03:10 ROUTER kernel: [   42.502164] ath: Country alpha2 being used: GB
Aug 20 15:03:10 ROUTER kernel: [   42.506827] ath: Regpair used: 0x37
Aug 20 15:03:10 ROUTER kernel: [   42.511189] ath: regdomain 0x833a dynamically updated by user
Aug 20 15:03:10 ROUTER kernel: [   42.552598] IPv6: ADDRCONF(NETDEV_CHANGE): br-lan: link becomes ready

Well I'm going to buy another router.
I didn't try replacing the power lead in the end as recommended on another thread.
I just tried connecting to the GUI and it crashed out again.
Bah..