Hi,
I'm facing some random reboot, then I've manage to get a stack trace from serial port :
[59591.008888] ------------[ cut here ]------------
[59591.013539] WARNING: CPU: 0 PID: 0 at net/sched/sch_generic.c:320 dev_watchdog+0x1ac/0x324
[59591.021799] NETDEV WATCHDOG: eth0 (mtk_soc_eth): transmit queue 0 timed out
[59591.028731] Modules linked in: pppoe ppp_async pppox ppp_generic nf_conntrack_ipv6 mt76x2e mt7603e mt76 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 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 ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables x_tables tun leds_gpio xhci_mtk xhci_plat_hcd xhci_pci xhci_hcd gpio_button_hotplug usbcore nls_base usb_common
[59591.097128] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.14.53 #0
[59591.103106] Stack : 00000000 00000000 00000000 00000000 805c7ad2 00000034 00000000 00000000
[59591.111442] 8055ed14 8055e8a7 804ed8cc 00000000 00000000 00000001 8fc09d68 1cc282d5
[59591.119774] 00000000 00000000 805c0000 00007310 00000000 00000183 00000008 00000000
[59591.128104] 00000000 80560000 00017b68 00000000 00000000 00000000 80580000 8035b988
[59591.136434] 00000009 00000140 00000000 8ffaf040 00000003 80285c70 01804017 01804057
[59591.144766] ...
[59591.147201] Call Trace:
[59591.149659] [<80010598>] show_stack+0x58/0x100
[59591.154092] [<8043412c>] dump_stack+0x9c/0xe0
[59591.158430] [<8002e328>] __warn+0xe0/0x114
[59591.162507] [<8002e38c>] warn_slowpath_fmt+0x30/0x3c
[59591.167451] [<8035b988>] dev_watchdog+0x1ac/0x324
[59591.172149] [<80086054>] call_timer_fn.isra.3+0x24/0x84
[59591.177348] [<8008626c>] run_timer_softirq+0x1b8/0x244
[59591.182475] [<804512a8>] __do_softirq+0x128/0x2ec
[59591.187162] [<80032a30>] irq_exit+0x98/0xcc
[59591.191345] [<8023a1ec>] plat_irq_dispatch+0xfc/0x138
[59591.196372] [<8000b5e8>] except_vec_vi_end+0xb8/0xc4
[59591.201313] [<8000cfb0>] r4k_wait_irqoff+0x1c/0x24
[59591.206104] [<8006630c>] do_idle+0xe4/0x168
[59591.210270] [<80066588>] cpu_startup_entry+0x24/0x2c
[59591.215215] [<80585bf0>] start_kernel+0x484/0x4a4
[59591.220038] ---[ end trace 02be6926695082d4 ]---
[59591.224684] mtk_soc_eth 1e100000.ethernet eth0: transmit timed out
[59591.230919] mtk_soc_eth 1e100000.ethernet eth0: dma_cfg:80000067
[59591.236922] mtk_soc_eth 1e100000.ethernet eth0: tx_ring=0, base=0eca0000, max=0, ctx=2745, dtx=2725, fdx=2716, next=2745
[59591.247792] mtk_soc_eth 1e100000.ethernet eth0: rx_ring=0, base=0de40000, max=0, calc=1838, drx=1840
[59591.651909] mtk_soc_eth 1e100000.ethernet: 0x100 = 0x5f60000c, 0x10c = 0x80818
[59591.664949] mtk_soc_eth 1e100000.ethernet: PPE started
[59973.008426] mtk_soc_eth 1e100000.ethernet eth0: transmit timed out
[59973.014614] mtk_soc_eth 1e100000.ethernet eth0: dma_cfg:80000067
[59973.020628] mtk_soc_eth 1e100000.ethernet eth0: tx_ring=0, base=0dc50000, max=0, ctx=3072, dtx=0, fdx=0, next=3072
[59973.030992] mtk_soc_eth 1e100000.ethernet eth0: rx_ring=0, base=0eb70000, max=0, calc=730, drx=731
[59973.450868] mtk_soc_eth 1e100000.ethernet: 0x100 = 0x5f60000c, 0x10c = 0x80818
[59973.464110] mtk_soc_eth 1e100000.ethernet: PPE started
[60583.007720] mtk_soc_eth 1e100000.ethernet eth0: transmit timed out
[60583.013899] mtk_soc_eth 1e100000.ethernet eth0: dma_cfg:80000067
[60583.019936] mtk_soc_eth 1e100000.ethernet eth0: tx_ring=0, base=0d1c0000, max=0, ctx=3072, dtx=0, fdx=0, next=3072
[60583.030317] mtk_soc_eth 1e100000.ethernet eth0: rx_ring=0, base=0d270000, max=0, calc=898, drx=899
[60583.450327] mtk_soc_eth 1e100000.ethernet: 0x100 = 0x5f60000c, 0x10c = 0x80818
[60583.463536] mtk_soc_eth 1e100000.ethernet: PPE started
[61483.006662] mtk_soc_eth 1e100000.ethernet eth0: transmit timed out
[61483.012841] mtk_soc_eth 1e100000.ethernet eth0: dma_cfg:80000067
[61483.018857] mtk_soc_eth 1e100000.ethernet eth0: tx_ring=0, base=0ef70000, max=0, ctx=3072, dtx=0, fdx=0, next=3072
[61483.029226] mtk_soc_eth 1e100000.ethernet eth0: rx_ring=0, base=0dfb0000, max=0, calc=969, drx=970
[61483.449773] mtk_soc_eth 1e100000.ethernet: 0x100 = 0x5f60000c, 0x10c = 0x80818
[61483.463163] mtk_soc_eth 1e100000.ethernet: PPE started
I've restarted the router by serial console as It wasn't completely hang.
What is concerned about this stack ???