After some time my RUT850 router just stalls, no data ist transmitted anymore. The connection ist still active (LTE) according to LEDs and admin page.
An error ist logged in sytem log:
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.010000] ------------[ cut here ]------------
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.010000] WARNING: CPU: 0 PID: 0 at net/sched/sch_generic.c:306 dev_watchdog+0x1d8/0x25c()
Tue Jun 30 10:23:41 2020 kern.info kernel: [ 5343.020000] NETDEV WATCHDOG: wwan0 (cdc_ncm): transmit queue 0 timed out
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.030000] Modules linked in: iptable_nat nf_nat_ipv4 ath9k ath9k_common pppoe ppp_async option l2tp_ppp ath9k_hw ath usb_wwan qmi_wwan pptp pppox ppp_mppe ppp_generic nf_conntrack_ipv6 nf_conntrack_ipv4 mac80211 ipt_REJECT ipt_MASQUERADE cfg80211 cdc_ncm xt_time xt_tcpudp xt_tcpmss xt_string xt_statistic xt_state xt_recent xt_quota2 xt_policy xt_nat xt_multiport xt_mark xt_mac xt_limit xt_length xt_id xt_hl xt_helper xt_esp xt_ecn xt_dscp xt_coova xt_conntrack xt_connmark xt_connlimit xt_connbytes xt_comment xt_TCPMSS xt_REDIRECT xt_LOG xt_HL xt_DSCP xt_CT xt_CLASSIFY usbserial usbnet ts_kmp ts_fsm ts_bm slhc nf_reject_ipv4 nf_nat_masquerade_ipv4 nf_nat_ftp nf_nat nf_log_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack_ftp lib80211_crypt_ccmp lib80211 iptable_raw iptable_mangle iptable_filter ipt_ah ipt_ECN ip_tables crc_ccitt compat cdc_wdm cdc_acm act_connmark nf_conntrack act_skbedit act_mirred em_u32 cls_u32 cls_tcindex cls_flow cls_route cls_fw sch_hfsc sch_ingress ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_raw ip6table_mangle ip6table_filter Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.180000] CPU: 0 PID: 0 Comm: swapper Not tainted 3.18.44 #1
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.180000] Stack : 00000000 00000000 00000000 00000000 803d42b2 00000032 00000000 80252634
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.180000] 00000001 803f58b8 8031a32c 80374aa3 00000000 803d34d8 80374dd8 803f58b8
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.180000] 00000200 00000001 00000004 800a3968 00000003 800807a4 00000132 803f58b8
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.180000] 8031d910 8036fc6c 00000000 00000000 00000000 00000000 00000000 00000000
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.180000] 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.180000] ...
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.220000] Call Trace:
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.220000] [<800713d4>] show_stack+0x50/0x84
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.220000] [<800808ac>] warn_slowpath_common+0x84/0xb4
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.230000] [<80080908>] warn_slowpath_fmt+0x2c/0x38
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.240000] [<80252634>] dev_watchdog+0x1d8/0x25c
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.240000] [<800ab41c>] call_timer_fn.isra.38+0x24/0x84
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.250000] [<800abc5c>] run_timer_softirq+0x1c0/0x200
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.250000] [<80082db4>] __do_softirq+0xf8/0x230
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.260000] [<80083118>] irq_exit+0x54/0x70
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.260000] [<80060830>] ret_from_irq+0x0/0x4
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.260000] [<8006e268>] r4k_wait_irqoff+0x18/0x20
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.270000] [<8009f904>] cpu_startup_entry+0xec/0x138
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.270000] [<80393b58>] start_kernel+0x428/0x440
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.280000]
Tue Jun 30 10:23:41 2020 kern.warn kernel: [ 5343.280000] ---[ end trace b4589365e754b658 ]---
Current Firmware Information:
Firmware version RUT850_R_00.01.04
Firmware build date 2020-05-15, 05:50:22
Kernel version 3.18.44
Bootloader version 2.0.1
STM8 firmware version 10