Unstable WiFi with mt76 on MT7628AN

[Rafał Miłecki]

On 04.07.2021 00:19, Rafał Miłecki wrote:
> It may be worth mentioning I found 1 WARNING in my dmesg. I can't tell
> if that has happened during any slow down / stall or not. Unforunately I
> don't have symbols in my backtrace.
> 
> [ 3245.170684] ------------[ cut here ]------------
> [ 3245.175434] WARNING: CPU: 0 PID: 627 at target-mipsel_24kc_musl/linux-ramips_mt76x8/mt76-2021-05-15-9d736545/mt7603/mac.c:206 0x835e44ac [mt7603e at bb8c9e4c+0x9520]

I've installed OpenWrt snapshot with debug symbols included. I
reproduced the WARNING. It doesn't seem to be related to slow downs /
stalls / no beacons.

[ 3090.333926] ------------[ cut here ]------------
[ 3090.338714] WARNING: CPU: 0 PID: 118 at target-mipsel_24kc_musl/linux-ramips_mt76x8/mt76-2021-06-06-22b69033/mt7603/mac.c:206 mt7603_filter_tx+0x16c/0x174 [mt7603e]
[ 3090.353623] Modules linked in: pppoe ppp_async iptable_nat xt_state xt_nat xt_conntrack xt_REDIRECT xt_MASQUERADE xt_FLOWOFFLOAD xt_CT pppox ppp_generic nf_nat nf_flow_table_hw nf_flow_table nf_conntrack mt7603e mt76 mac80211 ipt_REJECT cfg80211 xt_time xt_tcpudp xt_multiport xt_mark xt_mac xt_limit xt_comment xt_TCPMSS xt_LOG slhc nf_reject_ipv4 nf_log_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 iptable_mangle iptable_filter ip_tables crc_ccitt compat nf_log_ipv6 nf_log_common ip6table_mangle 
ip6table_filter ip6_tables ip6t_REJECT x_tables nf_reject_ipv6 sha256_generic libsha256 seqiv jitterentropy_rng drbg hmac ghash_generic gf128mul gcm ctr cmac ccm leds_gpio gpio_button_hotplug aead cryptomgr crypto_null crypto_hash
[ 3090.417635] CPU: 0 PID: 118 Comm: kworker/u3:0 Not tainted 5.4.128 #0
[ 3090.424186] Workqueue: napi_workq napi_workfn
[ 3090.428616] Stack : 80589abc 835744ac 00000009 00000000 00000000 8005b100 83d64cc0 00000000
[ 3090.437106]         00000017 83c98dbc 8057a6b8 83de5bec 80620000 00000001 83de5bc0 601c1e37
[ 3090.445583]         00000000 00000000 806393c0 00000000 716b726f 000000a0 6f775f69 6e666b72
[ 3090.454070]         00000000 00000099 00000000 000678fa 00000000 00000009 00000000 835744ac
[ 3090.462557]         00000009 00000000 00000000 83580000 00000000 802bbac8 00000000 80780000
[ 3090.471046]         ...
[ 3090.473522] Call Trace:
[ 3090.476017] [<80009c90>] show_stack+0x30/0x100
[ 3090.480542] [<80023ba0>] __warn+0xc0/0x10c
[ 3090.484693] [<80023c48>] warn_slowpath_fmt+0x5c/0xac
[ 3090.489754] [<835744ac>] mt7603_filter_tx+0x16c/0x174 [mt7603e]
[ 3090.495767] [<83574644>] mt7603_wtbl_set_ps+0x12c/0x134 [mt7603e]
[ 3090.501973] [<83571a1c>] mt7603_sta_ps+0x38/0x428 [mt7603e]
[ 3090.507669] [<835547f4>] mt76_rx_poll_complete+0x2e0/0x5b0 [mt76]
[ 3090.513860] [<8355153c>] mt76_dma_rx_poll+0x3d8/0xefc [mt76]
[ 3090.519634] [<8035b3dc>] __napi_poll+0x3c/0x10c
[ 3090.524227] [<8035b4ec>] napi_workfn+0x40/0x90
[ 3090.528751] [<8003b0e8>] process_one_work+0x220/0x480
[ 3090.533878] [<8003b4b0>] worker_thread+0x168/0x5c8
[ 3090.538759] [<800401ec>] kthread+0x138/0x140
[ 3090.543088] [<80005178>] ret_from_kernel_thread+0x14/0x1c
[ 3090.548577] ---[ end trace 068a759ed1654b52 ]---