[FS#606] Stall on Mediatek

[LEDE Bugs]

The following task has a new comment added:

FS#606 - Stall on Mediatek
User who did this - Karoly Kovacs (karesch)

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Hi Baptiste,

I could copy-paste this:
[  329.570000] WARNING: CPU: 3 PID: 0 at net/core/skbuff.c:4194 skb_try_coalesce+0x22c/0x36c()
[  329.580000] Modules linked in: pppoe ppp_async iptable_nat pppox ppp_generic nf_nat_ipv4 nf_conntrack_ipv6 nf_conntrack_ipv4 ipt_REJECT ipt_MASQUERADE 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_ecn xt_dscp xt_conntrack xt_connmark xt_connlimit xt_connbytes xt_comment xt_TCPMSS xt_REDIRECT xt_LOG xt_HL xt_DSCP xt_CLASSIFY slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_nat nf_log_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache iptable_mangle iptable_filter ipt_ECN ip_tables crc_ccitt sch_cake nf_conntrack act_skbedit act_mirred em_u32 cls_u32 cls_tcindex cls_flow cls_route cls_fw sch_tbf sch_htb sch_hfsc sch_ingress mt76x2e mt7603e ledtrig_usbport mt76 mac80211 cfg80211 compat ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables x_tables ifb leds_gpio xhci_mtk xhci_plat_hcd xhci_pci xhci_hcd gpio_button_hotplug usbcore nls_base usb_common
[  329.760000] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.4.52 #0
[  329.770000] Stack : 00000000 00000000 804c6862 00000033 00000000 00000000 80470000 804e0000
[  329.770000] 	  87c4bf6c 80469c83 803e4c74 00000003 00000000 804c367c 804837a0 804fade0
[  329.770000] 	  80466880 80063f7c 80470000 804e0000 8046e198 8046e19c 803e9588 87c21bdc
[  329.770000] 	  00000003 80061cc8 804837a0 804fade0 80466880 00000000 00000000 00c21bdc
[  329.770000] 	  00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[  329.770000] 	  ...
[  329.840000] Call Trace:
[  329.850000] [] show_stack+0x50/0x84
[  329.860000] [] dump_stack+0x84/0xbc
[  329.860000] [] warn_slowpath_common+0xa0/0xd0
[  329.880000] [] warn_slowpath_null+0x18/0x24
[  329.890000] [] skb_try_coalesce+0x22c/0x36c
[  329.900000] [] tcp_try_coalesce+0x4c/0xd0
[  329.910000] [] tcp_queue_rcv+0x60/0x12c
[  329.910000] [] tcp_rcv_established+0x4e4/0x61c
[  329.930000] [] tcp_v4_do_rcv+0xa0/0x1f8
[  329.930000] [] tcp_v4_rcv+0x6c0/0xa28
[  329.940000] [] ip_local_deliver_finish+0xd4/0x134
[  329.950000] [] ip_local_deliver+0xd0/0xe8
[  329.960000] [] ip_rcv+0x2b4/0x320
[  329.970000] [] __netif_receive_skb_core+0x6f0/0x914
[  329.980000] [] process_backlog+0xac/0x184
[  329.990000] [] net_rx_action+0x130/0x2e0
[  330.000000] [] __do_softirq+0x294/0x2e0
[  330.010000] [] irq_exit+0x78/0x94
[  330.020000] [] plat_irq_dispatch+0xb4/0xdc
[  330.030000] 
[  330.030000] ---[ end trace 8bd5e0303178b765 ]---
[ 1137.390000] INFO: rcu_sched detected stalls on CPUs/tasks:
[ 1137.400000] 	2-...: (0 ticks this GP) idle=5f8/0/0 softirq=76940/76940 fqs=0 
[ 1137.410000] 	(detected by 3, t=6004 jiffies, g=32609, c=32608, q=4661)
[ 1137.420000] Task dump for CPU 2:
[ 1137.430000] swapper/2       R running      0     0      1 0x00100000
[ 1137.440000] Stack : 00000000 001c5bc4 00000108 05080000 00000000 18c45114 804b72a4 80460000
[ 1137.440000] 	  8046675c 00000001 00000000 804665e0 80466724 80460000 00000000 800134fc
[ 1137.440000] 	  1100fc03 00000002 87c72000 87c73ec0 80460000 8005dc48 1100fc03 00000002
[ 1137.440000] 	  00000000 80460000 804b72a4 8005dc40 80460000 8001b0c8 1100fc03 00000000
[ 1137.440000] 	  00000004 804664a0 000000a0 8001b0d0 00000000 00000000 00000000 00000000
[ 1137.440000] 	  ...
[ 1137.510000] Call Trace:
[ 1137.520000] [] __schedule+0x574/0x758
[ 1137.530000] [] r4k_wait_irqoff+0x0/0x20
[ 1137.540000] 
[ 1137.540000] rcu_sched kthread starved for 6017 jiffies! g32609 c32608 f0x0 s3 ->state=0x1
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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=606#comment2194