Advice: Repeated crash BT HomeHub 5.0 Type A

Installing and Using OpenWrt
1

Hopefully someone can advise, as I'm running out of ideas. Whilst I'm an IT Professional, I'm running out of ideas.

Since approx last week, periodically my BT HomeHub 5.0 Type A appears to crash, requiring restart before traffic will again be passed. DSL remains connected, but traffic forwarding just stops (ping direct from LuCI to 9.9.9.9 example fails). It will again function for a while before crashing again. The device has been working fine for months without incident, with no modifications or upgrades.

I've updated to 7.5.0, with no success.

Each time, appears to be a kernel dump in net/sched/sch_generic.c as follows (includes last events logged for context):

[  108.103635] br-lan: port 3(wlan0) entered blocking state
[  108.108525] br-lan: port 3(wlan0) entered forwarding state
[14780.880968] ------------[ cut here ]------------
[14780.884158] WARNING: CPU: 1 PID: 0 at net/sched/sch_generic.c:320 0x803f0920
[14780.891274] NETDEV WATCHDOG: dsl0 (): transmit queue 0 timed out
[14780.897245] Modules linked in: ltq_ptm_vr9 ath9k ath9k_common ath9k_hw ath10k_pci ath10k_core ath pppoe 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 pppox ppp_async owl_loader 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 ltq_deu_vr9 iptable_mangle iptable_filter ip_tables crc_ccitt compat drv_dsl_cpe_api drv_mei_cpe nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables ip6t_REJECT x_tables nf_reject_ipv6 pppoatm ppp_generic slhc br2684 atm drv_ifxos dwc2 gpio_button_hotplug
[14780.969152] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.14.171 #0
[14780.975109] Stack : 00000000 00000000 00000000 ffffffff 00000000 00000000 00000000 00000000
[14780.983460]         00000000 00000000 00000000 00000000 00000000 00000001 87c0fd48 74ab3cb6
[14780.991812]         87c0fde0 00000000 00000000 00010000 00000038 80511998 00000008 00000000
[14781.000169]         00000153 26000000 00000152 00000000 87c0fd28 00000000 00000000 00000009
[14781.008528]         803f0920 00000140 80611fc4 ffffffff 00000000 00000000 00000004 80770004
[14781.016883]         ...
[14781.019314] Call Trace:
[14781.019345] [<80511998>] 0x80511998
[14781.025273] [<803f0920>] 0x803f0920
[14781.028728] [<80010e44>] 0x80010e44
[14781.032221] [<80010e4c>] 0x80010e4c
[14781.035693] [<804fa150>] 0x804fa150
[14781.039188] [<800815cc>] 0x800815cc
[14781.042658] [<80036a80>] 0x80036a80
[14781.046148] [<803f0920>] 0x803f0920
[14781.049664] [<80036b50>] 0x80036b50
[14781.053124] [<8009b668>] 0x8009b668
[14781.056585] [<803f0920>] 0x803f0920
[14781.060096] [<803f0704>] 0x803f0704
[14781.063557] [<8009a300>] 0x8009a300
[14781.067035] [<8009a650>] 0x8009a650
[14781.070517] [<80094f64>] 0x80094f64
[14781.073997] [<8051a668>] 0x8051a668
[14781.077488] [<8003bb60>] 0x8003bb60
[14781.080981] [<80293300>] 0x80293300
[14781.084443] [<8000b728>] 0x8000b728
[14781.087916] 
[14781.089431] ---[ end trace f5f4a151c4abfa41 ]---

System log reports very similar:

Wed Apr 15 11:16:52 2020 kern.warn kernel: [14780.880968] ------------[ cut here ]------------
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14780.884158] WARNING: CPU: 1 PID: 0 at net/sched/sch_generic.c:320 0x803f0920
Wed Apr 15 11:16:52 2020 kern.info kernel: [14780.891274] NETDEV WATCHDOG: dsl0 (): transmit queue 0 timed out
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14780.897245] Modules linked in: ltq_ptm_vr9 ath9k ath9k_common ath9k_hw ath10k_pci ath10k_core ath pppoe 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 pppox ppp_async owl_loader 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 ltq_deu_vr9 iptable_mangle iptable_filter ip_tables crc_ccitt compat drv_dsl_cpe_api drv_mei_cpe nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables ip6t_REJECT x_tables nf_reject_ipv6 pppoatm ppp_generic slhc br2684 atm drv_ifxos dwc2 gpio_button_hotplug
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14780.969152] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.14.171 #0
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14780.975109] Stack : 00000000 00000000 00000000 ffffffff 00000000 00000000 00000000 00000000
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14780.983460]         00000000 00000000 00000000 00000000 00000000 00000001 87c0fd48 74ab3cb6
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14780.991812]         87c0fde0 00000000 00000000 00010000 00000038 80511998 00000008 00000000
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.000169]         00000153 26000000 00000152 00000000 87c0fd28 00000000 00000000 00000009
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.008528]         803f0920 00000140 80611fc4 ffffffff 00000000 00000000 00000004 80770004
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.016883]         ...
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.019314] Call Trace:
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.019345] [<80511998>] 0x80511998
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.025273] [<803f0920>] 0x803f0920
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.028728] [<80010e44>] 0x80010e44
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.032221] [<80010e4c>] 0x80010e4c
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.035693] [<804fa150>] 0x804fa150
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.039188] [<800815cc>] 0x800815cc
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.042658] [<80036a80>] 0x80036a80
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.046148] [<803f0920>] 0x803f0920
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.049664] [<80036b50>] 0x80036b50
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.053124] [<8009b668>] 0x8009b668
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.056585] [<803f0920>] 0x803f0920
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.060096] [<803f0704>] 0x803f0704
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.063557] [<8009a300>] 0x8009a300
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.067035] [<8009a650>] 0x8009a650
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.070517] [<80094f64>] 0x80094f64
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.073997] [<8051a668>] 0x8051a668
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.077488] [<8003bb60>] 0x8003bb60
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.080981] [<80293300>] 0x80293300
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.084443] [<8000b728>] 0x8000b728
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.087916]
Wed Apr 15 11:16:52 2020 kern.warn kernel: [14781.089431] ---[ end trace f5f4a151c4abfa41 ]---
2

No help unfortunately, but it looks like an existing but older unresolved bug 494.

Without the debug symbols, at a guess the network device timed out blocked and the timer expired. Could be software or hardware (or maybe even remote DSL issues). Having a spare HH5 for testing would help rule out the hardware.

People are still somehow still selling them on fleabay for a tenner during this lockdown!

(I use a flakey spare HH5 that randomly reboots every few days but still useful for testing OpenWRT updates.)

3

Many thanks. Considered it might be a hardware bug, so after posting sourced another HH for comparison. Also have a Draytek I can configure and swap in, just to see if the DSL has suddenly become unreliable, and go from there.

4

Hi
I see you’re on kernel 4.14.171. I know you said you haven’t updated. So that’s a OpenWRT19.07.2 or 18.06.8? If it was previously stable why not go back to 19.07.1. or earlier.

5

Yeah, was using 18.06.8 until attempting to fix the original problem. I upgraded to 17 to see if it would resolve the original issue; but still same....

6

You probably meant 19.07[.2]