EA4500 5GHz Hangs the router

Hi guys,
I installed the latest LEDE build on my Ea4500 (kirkwood - viper).
After enabling the 5GHZ wifi interface, the router becomes mostly unusable (ping > 10000ms).
I was able to grab system and kernel logs

Please help :frowning:

[  653.518147] [<c001a0c0>] (tasklet_action) from [<c00199a8>] (__do_softirq+0xe4/0x230)
[  653.526025]  r7:c0575e10 r6:00000006 r5:00000024 r4:40000002
[  653.531717] [<c00198c4>] (__do_softirq) from [<c0019b20>] (run_ksoftirqd+0x2c/0x5c)
[  653.539429]  r10:00000000 r9:00000000 r8:00000001 r7:00000000 r6:c05579c8 r5:c7840000
[  653.547304]  r4:c7805f20
[  653.549858] [<c0019af4>] (run_ksoftirqd) from [<c0031bf4>] (smpboot_thread_fn+0x14c/0x160)
[  653.558183] [<c0031aa8>] (smpboot_thread_fn) from [<c002e7d0>] (kthread+0xd8/0xec)
[  653.565809]  r9:00000000 r8:00000000 r7:c0031aa8 r6:c7805f20 r5:00000000 r4:c7805f40
[  653.573591] [<c002e6f8>] (kthread) from [<c000a2e8>] (ret_from_fork+0x14/0x2c)
[  653.580865]  r7:00000000 r6:00000000 r5:c002e6f8 r4:c7805f40
[  653.586563] ---[ end trace 7a627567bca50a08 ]---
[  653.591199] ------------[ cut here ]------------
[  653.595921] WARNING: CPU: 0 PID: 3 at backports-2017-11-01/net/mac80211/rx.c:4362 ieee80211_rx_napi+0x8c/0x87c [mac80211]
[  653.606941] Modules linked in: pppoe ppp_async pppox ppp_generic nf_conntrack_ipv6 mwl8k 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_CT slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables x_tables
[  653.660899] CPU: 0 PID: 3 Comm: ksoftirqd/0 Tainted: G        W       4.9.86 #0
[  653.668251] Hardware name: Marvell Kirkwood (Flattened Device Tree)
[  653.674540] Backtrace: 
[  653.677020] [<c000d204>] (dump_backtrace) from [<c000d4c8>] (show_stack+0x18/0x1c)
[  653.684627]  r7:bf11fda0 r6:00000000 r5:bf15223a r4:00000000
[  653.690331] [<c000d4b0>] (show_stack) from [<c01cb6c0>] (dump_stack+0x20/0x28)
[  653.697605] [<c01cb6a0>] (dump_stack) from [<c0016d64>] (__warn+0xd4/0x100)
[  653.704607] [<c0016c90>] (__warn) from [<c0016e48>] (warn_slowpath_null+0x28/0x30)
[  653.712226]  r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7311878 r5:c7310b80 r4:c6eaf600
[  653.720088] [<c0016e20>] (warn_slowpath_null) from [<bf11fda0>] (ieee80211_rx_napi+0x8c/0x87c [mac80211])
[  653.729840] [<bf11fd14>] (ieee80211_rx_napi [mac80211]) from [<bf0fe0d8>] (ieee80211_tasklet_handler+0x78/0xb4 [mac80211])
[  653.740952]  r10:00000100 r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7310fa4 r5:c7310b80
[  653.748834]  r4:c6eaf600
[  653.751445] [<bf0fe060>] (ieee80211_tasklet_handler [mac80211]) from [<c001a150>] (tasklet_action+0x90/0xd4)
[  653.761336]  r7:c0575e10 r6:c7311c24 r5:00000000 r4:c05579b4
[  653.767042] [<c001a0c0>] (tasklet_action) from [<c00199a8>] (__do_softirq+0xe4/0x230)
[  653.774904]  r7:c0575e10 r6:00000006 r5:00000024 r4:40000002
[  653.780611] [<c00198c4>] (__do_softirq) from [<c0019b20>] (run_ksoftirqd+0x2c/0x5c)
[  653.788315]  r10:00000000 r9:00000000 r8:00000001 r7:00000000 r6:c05579c8 r5:c7840000
[  653.796192]  r4:c7805f20
[  653.798744] [<c0019af4>] (run_ksoftirqd) from [<c0031bf4>] (smpboot_thread_fn+0x14c/0x160)
[  653.807069] [<c0031aa8>] (smpboot_thread_fn) from [<c002e7d0>] (kthread+0xd8/0xec)
[  653.814679]  r9:00000000 r8:00000000 r7:c0031aa8 r6:c7805f20 r5:00000000 r4:c7805f40
[  653.822474] [<c002e6f8>] (kthread) from [<c000a2e8>] (ret_from_fork+0x14/0x2c)
[  653.829743]  r7:00000000 r6:00000000 r5:c002e6f8 r4:c7805f40
[  653.835439] ---[ end trace 7a627567bca50a09 ]---
[  653.875413] ------------[ cut here ]------------
[  653.880176] WARNING: CPU: 0 PID: 3 at backports-2017-11-01/net/mac80211/rx.c:4362 ieee80211_rx_napi+0x8c/0x87c [mac80211]
[  653.891212] Modules linked in: pppoe ppp_async pppox ppp_generic nf_conntrack_ipv6 mwl8k 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_CT slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables x_tables
[  653.945193] CPU: 0 PID: 3 Comm: ksoftirqd/0 Tainted: G        W       4.9.86 #0
[  653.952535] Hardware name: Marvell Kirkwood (Flattened Device Tree)
[  653.958835] Backtrace: 
[  653.961314] [<c000d204>] (dump_backtrace) from [<c000d4c8>] (show_stack+0x18/0x1c)
[  653.968933]  r7:bf11fda0 r6:00000000 r5:bf15223a r4:00000000
[  653.974624] [<c000d4b0>] (show_stack) from [<c01cb6c0>] (dump_stack+0x20/0x28)
[  653.981908] [<c01cb6a0>] (dump_stack) from [<c0016d64>] (__warn+0xd4/0x100)
[  653.988923] [<c0016c90>] (__warn) from [<c0016e48>] (warn_slowpath_null+0x28/0x30)
[  653.996541]  r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7311878 r5:c7310b80 r4:c6ed23c0
[  654.004396] [<c0016e20>] (warn_slowpath_null) from [<bf11fda0>] (ieee80211_rx_napi+0x8c/0x87c [mac80211])
[  654.014154] [<bf11fd14>] (ieee80211_rx_napi [mac80211]) from [<bf0fe0d8>] (ieee80211_tasklet_handler+0x78/0xb4 [mac80211])
[  654.025270]  r10:00000100 r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7310fa4 r5:c7310b80
[  654.033134]  r4:c6ed23c0
[  654.035762] [<bf0fe060>] (ieee80211_tasklet_handler [mac80211]) from [<c001a150>] (tasklet_action+0x90/0xd4)
[  654.045653]  r7:c0575e10 r6:c7311c24 r5:00000000 r4:c05579b4
[  654.051344] [<c001a0c0>] (tasklet_action) from [<c00199a8>] (__do_softirq+0xe4/0x230)
[  654.059227]  r7:c0575e10 r6:00000006 r5:00000024 r4:40000002
[  654.064919] [<c00198c4>] (__do_softirq) from [<c0019b20>] (run_ksoftirqd+0x2c/0x5c)
[  654.072632]  r10:00000000 r9:00000000 r8:00000001 r7:00000000 r6:c05579c8 r5:c7840000
[  654.080511]  r4:c7805f20
[  654.083072] [<c0019af4>] (run_ksoftirqd) from [<c0031bf4>] (smpboot_thread_fn+0x14c/0x160)
[  654.091399] [<c0031aa8>] (smpboot_thread_fn) from [<c002e7d0>] (kthread+0xd8/0xec)
[  654.099020]  r9:00000000 r8:00000000 r7:c0031aa8 r6:c7805f20 r5:00000000 r4:c7805f40
[  654.106816] [<c002e6f8>] (kthread) from [<c000a2e8>] (ret_from_fork+0x14/0x2c)
[  654.114069]  r7:00000000 r6:00000000 r5:c002e6f8 r4:c7805f40
[  654.119765] ---[ end trace 7a627567bca50a0a ]---
[  654.124402] ------------[ cut here ]------------
[  654.129126] WARNING: CPU: 0 PID: 3 at backports-2017-11-01/net/mac80211/rx.c:4362 ieee80211_rx_napi+0x8c/0x87c [mac80211]
[  654.140145] Modules linked in: pppoe ppp_async pppox ppp_generic nf_conntrack_ipv6 mwl8k 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_CT slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables x_tables
[  654.194101] CPU: 0 PID: 3 Comm: ksoftirqd/0 Tainted: G        W       4.9.86 #0
[  654.201454] Hardware name: Marvell Kirkwood (Flattened Device Tree)
[  654.207755] Backtrace: 
[  654.210229] [<c000d204>] (dump_backtrace) from [<c000d4c8>] (show_stack+0x18/0x1c)
[  654.217853]  r7:bf11fda0 r6:00000000 r5:bf15223a r4:00000000
[  654.223544] [<c000d4b0>] (show_stack) from [<c01cb6c0>] (dump_stack+0x20/0x28)
[  654.230825] [<c01cb6a0>] (dump_stack) from [<c0016d64>] (__warn+0xd4/0x100)
[  654.237842] [<c0016c90>] (__warn) from [<c0016e48>] (warn_slowpath_null+0x28/0x30)
[  654.245463]  r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7311878 r5:c7310b80 r4:c6ed2180
[  654.253311] [<c0016e20>] (warn_slowpath_null) from [<bf11fda0>] (ieee80211_rx_napi+0x8c/0x87c [mac80211])
[  654.263059] [<bf11fd14>] (ieee80211_rx_napi [mac80211]) from [<bf0fe0d8>] (ieee80211_tasklet_handler+0x78/0xb4 [mac80211])
[  654.274172]  r10:00000100 r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7310fa4 r5:c7310b80
[  654.282053]  r4:c6ed2180
[  654.284665] [<bf0fe060>] (ieee80211_tasklet_handler [mac80211]) from [<c001a150>] (tasklet_action+0x90/0xd4)
[  654.294557]  r7:c0575e10 r6:c7311c24 r5:00000000 r4:c05579b4
[  654.300263] [<c001a0c0>] (tasklet_action) from [<c00199a8>] (__do_softirq+0xe4/0x230)
[  654.308148]  r7:c0575e10 r6:00000006 r5:00000024 r4:40000002
[  654.313840] [<c00198c4>] (__do_softirq) from [<c0019b20>] (run_ksoftirqd+0x2c/0x5c)
[  654.321552]  r10:00000000 r9:00000000 r8:00000001 r7:00000000 r6:c05579c8 r5:c7840000
[  654.329428]  r4:c7805f20
[  654.331981] [<c0019af4>] (run_ksoftirqd) from [<c0031bf4>] (smpboot_thread_fn+0x14c/0x160)
[  654.340307] [<c0031aa8>] (smpboot_thread_fn) from [<c002e7d0>] (kthread+0xd8/0xec)
[  654.347931]  r9:00000000 r8:00000000 r7:c0031aa8 r6:c7805f20 r5:00000000 r4:c7805f40
[  654.355729] [<c002e6f8>] (kthread) from [<c000a2e8>] (ret_from_fork+0x14/0x2c)
[  654.362981]  r7:00000000 r6:00000000 r5:c002e6f8 r4:c7805f40
[  654.368678] ---[ end trace 7a627567bca50a0b ]---
[  654.373313] ------------[ cut here ]------------
[  654.378036] WARNING: CPU: 0 PID: 3 at backports-2017-11-01/net/mac80211/rx.c:4362 ieee80211_rx_napi+0x8c/0x87c [mac80211]
[  654.389057] Modules linked in: pppoe ppp_async pppox ppp_generic nf_conntrack_ipv6 mwl8k 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_CT slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables x_tables
[  654.443022] CPU: 0 PID: 3 Comm: ksoftirqd/0 Tainted: G        W       4.9.86 #0
[  654.450373] Hardware name: Marvell Kirkwood (Flattened Device Tree)
[  654.456676] Backtrace: 
[  654.459151] [<c000d204>] (dump_backtrace) from [<c000d4c8>] (show_stack+0x18/0x1c)
[  654.466774]  r7:bf11fda0 r6:00000000 r5:bf15223a r4:00000000
[  654.472465] [<c000d4b0>] (show_stack) from [<c01cb6c0>] (dump_stack+0x20/0x28)
[  654.479745] [<c01cb6a0>] (dump_stack) from [<c0016d64>] (__warn+0xd4/0x100)
[  654.486755] [<c0016c90>] (__warn) from [<c0016e48>] (warn_slowpath_null+0x28/0x30)
[  654.494361]  r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7311878 r5:c7310b80 r4:c6ed2240
[  654.502221] [<c0016e20>] (warn_slowpath_null) from [<bf11fda0>] (ieee80211_rx_napi+0x8c/0x87c [mac80211])
[  654.511973] [<bf11fd14>] (ieee80211_rx_napi [mac80211]) from [<bf0fe0d8>] (ieee80211_tasklet_handler+0x78/0xb4 [mac80211])
[  654.523084]  r10:00000100 r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7310fa4 r5:c7310b80
[  654.530956]  r4:c6ed2240
[  654.533568] [<bf0fe060>] (ieee80211_tasklet_handler [mac80211]) from [<c001a150>] (tasklet_action+0x90/0xd4)
[  654.543460]  r7:c0575e10 r6:c7311c24 r5:00000000 r4:c05579b4
[  654.549165] [<c001a0c0>] (tasklet_action) from [<c00199a8>] (__do_softirq+0xe4/0x230)
[  654.557043]  r7:c0575e10 r6:00000006 r5:00000024 r4:40000002
[  654.562735] [<c00198c4>] (__do_softirq) from [<c0019b20>] (run_ksoftirqd+0x2c/0x5c)
[  654.570448]  r10:00000000 r9:00000000 r8:00000001 r7:00000000 r6:c05579c8 r5:c7840000
[  654.578323]  r4:c7805f20
[  654.580875] [<c0019af4>] (run_ksoftirqd) from [<c0031bf4>] (smpboot_thread_fn+0x14c/0x160)
[  654.589202] [<c0031aa8>] (smpboot_thread_fn) from [<c002e7d0>] (kthread+0xd8/0xec)
[  654.596826]  r9:00000000 r8:00000000 r7:c0031aa8 r6:c7805f20 r5:00000000 r4:c7805f40
[  654.604609] [<c002e6f8>] (kthread) from [<c000a2e8>] (ret_from_fork+0x14/0x2c)
[  654.611884]  r7:00000000 r6:00000000 r5:c002e6f8 r4:c7805f40
[  654.617580] ---[ end trace 7a627567bca50a0c ]---
[  654.622217] ------------[ cut here ]------------
[  654.626938] WARNING: CPU: 0 PID: 3 at backports-2017-11-01/net/mac80211/rx.c:4362 ieee80211_rx_napi+0x8c/0x87c [mac80211]
[  654.637960] Modules linked in: pppoe ppp_async pppox ppp_generic nf_conntrack_ipv6 mwl8k 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_CT slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables x_tables
[  654.691917] CPU: 0 PID: 3 Comm: ksoftirqd/0 Tainted: G        W       4.9.86 #0
[  654.699269] Hardware name: Marvell Kirkwood (Flattened Device Tree)
[  654.705571] Backtrace: 
[  654.708047] [<c000d204>] (dump_backtrace) from [<c000d4c8>] (show_stack+0x18/0x1c)
[  654.715672]  r7:bf11fda0 r6:00000000 r5:bf15223a r4:00000000
[  654.721361] [<c000d4b0>] (show_stack) from [<c01cb6c0>] (dump_stack+0x20/0x28)
[  654.728641] [<c01cb6a0>] (dump_stack) from [<c0016d64>] (__warn+0xd4/0x100)
[  654.735659] [<c0016c90>] (__warn) from [<c0016e48>] (warn_slowpath_null+0x28/0x30)
[  654.743264]  r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7311878 r5:c7310b80 r4:c6ed2900
[  654.751125] [<c0016e20>] (warn_slowpath_null) from [<bf11fda0>] (ieee80211_rx_napi+0x8c/0x87c [mac80211])
[  654.760877] [<bf11fd14>] (ieee80211_rx_napi [mac80211]) from [<bf0fe0d8>] (ieee80211_tasklet_handler+0x78/0xb4 [mac80211])
[  654.771987]  r10:00000100 r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7310fa4 r5:c7310b80
[  654.779860]  r4:c6ed2900
[  654.782472] [<bf0fe060>] (ieee80211_tasklet_handler [mac80211]) from [<c001a150>] (tasklet_action+0x90/0xd4)
[  654.792363]  r7:c0575e10 r6:c7311c24 r5:00000000 r4:c05579b4
[  654.798069] [<c001a0c0>] (tasklet_action) from [<c00199a8>] (__do_softirq+0xe4/0x230)
[  654.805955]  r7:c0575e10 r6:00000006 r5:00000024 r4:40000002
[  654.811648] [<c00198c4>] (__do_softirq) from [<c0019b20>] (run_ksoftirqd+0x2c/0x5c)
[  654.819360]  r10:00000000 r9:00000000 r8:00000001 r7:00000000 r6:c05579c8 r5:c7840000
[  654.827234]  r4:c7805f20
[  654.829788] [<c0019af4>] (run_ksoftirqd) from [<c0031bf4>] (smpboot_thread_fn+0x14c/0x160)
[  654.838114] [<c0031aa8>] (smpboot_thread_fn) from [<c002e7d0>] (kthread+0xd8/0xec)
[  654.845745]  r9:00000000 r8:00000000 r7:c0031aa8 r6:c7805f20 r5:00000000 r4:c7805f40
[  654.853530] [<c002e6f8>] (kthread) from [<c000a2e8>] (ret_from_fork+0x14/0x2c)
[  654.860805]  r7:00000000 r6:00000000 r5:c002e6f8 r4:c7805f40
[  654.866501] ---[ end trace 7a627567bca50a0d ]---
[  654.871138] ------------[ cut here ]------------
[  654.875862] WARNING: CPU: 0 PID: 3 at backports-2017-11-01/net/mac80211/rx.c:4362 ieee80211_rx_napi+0x8c/0x87c [mac80211]
[  654.886881] Modules linked in: pppoe ppp_async pppox ppp_generic nf_conntrack_ipv6 mwl8k 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_CT slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables x_tables
[  654.940838] CPU: 0 PID: 3 Comm: ksoftirqd/0 Tainted: G        W       4.9.86 #0
[  654.948190] Hardware name: Marvell Kirkwood (Flattened Device Tree)
[  654.954479] Backtrace: 
[  654.956960] [<c000d204>] (dump_backtrace) from [<c000d4c8>] (show_stack+0x18/0x1c)
[  654.964565]  r7:bf11fda0 r6:00000000 r5:bf15223a r4:00000000
[  654.970271] [<c000d4b0>] (show_stack) from [<c01cb6c0>] (dump_stack+0x20/0x28)
[  654.977543] [<c01cb6a0>] (dump_stack) from [<c0016d64>] (__warn+0xd4/0x100)
[  654.984537] [<c0016c90>] (__warn) from [<c0016e48>] (warn_slowpath_null+0x28/0x30)
[  654.992160]  r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7311878 r5:c7310b80 r4:c6ed2a80
[  655.000028] [<c0016e20>] (warn_slowpath_null) from [<bf11fda0>] (ieee80211_rx_napi+0x8c/0x87c [mac80211])
[  655.009785] [<bf11fd14>] (ieee80211_rx_napi [mac80211]) from [<bf0fe0d8>] (ieee80211_tasklet_handler+0x78/0xb4 [mac80211])
[  655.020900]  r10:00000100 r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7310fa4 r5:c7310b80
[  655.028772]  r4:c6ed2a80
[  655.031385] [<bf0fe060>] (ieee80211_tasklet_handler [mac80211]) from [<c001a150>] (tasklet_action+0x90/0xd4)
[  655.041275]  r7:c0575e10 r6:c7311c24 r5:00000000 r4:c05579b4
[  655.046982] [<c001a0c0>] (tasklet_ac






Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.542627] [<c0016e20>] (warn_slowpath_null) from [<bf11fda0>] (ieee80211_rx_napi+0x8c/0x87c [mac80211])
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.552382] [<bf11fd14>] (ieee80211_rx_napi [mac80211]) from [<bf0fe0d8>] (ieee80211_tasklet_handler+0x78/0xb4 [mac80211])
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.563494]  r10:00000100 r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7310fa4 r5:c7310b80
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.571373]  r4:c6ea7c00
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.573989] [<bf0fe060>] (ieee80211_tasklet_handler [mac80211]) from [<c001a150>] (tasklet_action+0x90/0xd4)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.583878]  r7:c0575e10 r6:c7311c24 r5:00000000 r4:c05579b4
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.589584] [<c001a0c0>] (tasklet_action) from [<c00199a8>] (__do_softirq+0xe4/0x230)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.597470]  r7:c0575e10 r6:00000006 r5:00000024 r4:40000002
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.603162] [<c00198c4>] (__do_softirq) from [<c0019b20>] (run_ksoftirqd+0x2c/0x5c)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.610874]  r10:00000000 r9:00000000 r8:00000001 r7:00000000 r6:c05579c8 r5:c7840000
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.618750]  r4:c7805f20
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.621305] [<c0019af4>] (run_ksoftirqd) from [<c0031bf4>] (smpboot_thread_fn+0x14c/0x160)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.629632] [<c0031aa8>] (smpboot_thread_fn) from [<c002e7d0>] (kthread+0xd8/0xec)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.637254]  r9:00000000 r8:00000000 r7:c0031aa8 r6:c7805f20 r5:00000000 r4:c7805f40
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.645037] [<c002e6f8>] (kthread) from [<c000a2e8>] (ret_from_fork+0x14/0x2c)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.652310]  r7:00000000 r6:00000000 r5:c002e6f8 r4:c7805f40
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.658007] ---[ end trace 7a627567bca50b72 ]---
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.662645] ------------[ cut here ]------------
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.667368] WARNING: CPU: 0 PID: 3 at backports-2017-11-01/net/mac80211/rx.c:4362 ieee80211_rx_napi+0x8c/0x87c [mac80211]
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.678387] Modules linked in: pppoe ppp_async pppox ppp_generic nf_conntrack_ipv6 mwl8k 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_CT slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables x_tables
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.732352] CPU: 0 PID: 3 Comm: ksoftirqd/0 Tainted: G        W       4.9.86 #0
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.739709] Hardware name: Marvell Kirkwood (Flattened Device Tree)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.746016] Backtrace:
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.748490] [<c000d204>] (dump_backtrace) from [<c000d4c8>] (show_stack+0x18/0x1c)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.756113]  r7:bf11fda0 r6:00000000 r5:bf15223a r4:00000000
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.761805] [<c000d4b0>] (show_stack) from [<c01cb6c0>] (dump_stack+0x20/0x28)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.769085] [<c01cb6a0>] (dump_stack) from [<c0016d64>] (__warn+0xd4/0x100)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.776103] [<c0016c90>] (__warn) from [<c0016e48>] (warn_slowpath_null+0x28/0x30)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.783708]  r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7311878 r5:c7310b80 r4:c6ead540
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.791569] [<c0016e20>] (warn_slowpath_null) from [<bf11fda0>] (ieee80211_rx_napi+0x8c/0x87c [mac80211])
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.801318] [<bf11fd14>] (ieee80211_rx_napi [mac80211]) from [<bf0fe0d8>] (ieee80211_tasklet_handler+0x78/0xb4 [mac80211])
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.812431]  r10:00000100 r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7310fa4 r5:c7310b80
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.820304]  r4:c6ead540
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.822916] [<bf0fe060>] (ieee80211_tasklet_handler [mac80211]) from [<c001a150>] (tasklet_action+0x90/0xd4)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.832807]  r7:c0575e10 r6:c7311c24 r5:00000000 r4:c05579b4
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.838513] [<c001a0c0>] (tasklet_action) from [<c00199a8>] (__do_softirq+0xe4/0x230)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.846399]  r7:c0575e10 r6:00000006 r5:00000024 r4:40000002
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.852091] [<c00198c4>] (__do_softirq) from [<c0019b20>] (run_ksoftirqd+0x2c/0x5c)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.859804]  r10:00000000 r9:00000000 r8:00000001 r7:00000000 r6:c05579c8 r5:c7840000
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.867679]  r4:c7805f20
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.870233] [<c0019af4>] (run_ksoftirqd) from [<c0031bf4>] (smpboot_thread_fn+0x14c/0x160)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.878559] [<c0031aa8>] (smpboot_thread_fn) from [<c002e7d0>] (kthread+0xd8/0xec)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.886183]  r9:00000000 r8:00000000 r7:c0031aa8 r6:c7805f20 r5:00000000 r4:c7805f40
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.893966] [<c002e6f8>] (kthread) from [<c000a2e8>] (ret_from_fork+0x14/0x2c)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.901239]  r7:00000000 r6:00000000 r5:c002e6f8 r4:c7805f40
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.906937] ---[ end trace 7a627567bca50b73 ]---
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.911573] ------------[ cut here ]------------
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.916295] WARNING: CPU: 0 PID: 3 at backports-2017-11-01/net/mac80211/rx.c:4362 ieee80211_rx_napi+0x8c/0x87c [mac80211]
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.927307] Modules linked in: pppoe ppp_async pppox ppp_generic nf_conntrack_ipv6 mwl8k 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_CT slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables x_tables
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.981274] CPU: 0 PID: 3 Comm: ksoftirqd/0 Tainted: G        W       4.9.86 #0
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.988626] Hardware name: Marvell Kirkwood (Flattened Device Tree)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.994915] Backtrace:
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  744.997394] [<c000d204>] (dump_backtrace) from [<c000d4c8>] (show_stack+0x18/0x1c)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.005001]  r7:bf11fda0 r6:00000000 r5:bf15223a r4:00000000
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.010709] [<c000d4b0>] (show_stack) from [<c01cb6c0>] (dump_stack+0x20/0x28)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.017989] [<c01cb6a0>] (dump_stack) from [<c0016d64>] (__warn+0xd4/0x100)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.024991] [<c0016c90>] (__warn) from [<c0016e48>] (warn_slowpath_null+0x28/0x30)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.032611]  r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7311878 r5:c7310b80 r4:c6ead3c0
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.040473] [<c0016e20>] (warn_slowpath_null) from [<bf11fda0>] (ieee80211_rx_napi+0x8c/0x87c [mac80211])
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.050226] [<bf11fd14>] (ieee80211_rx_napi [mac80211]) from [<bf0fe0d8>] (ieee80211_tasklet_handler+0x78/0xb4 [mac80211])
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.061343]  r10:00000100 r9:c0575e18 r8:c7840000 r7:c7310fb0 r6:c7310fa4 r5:c7310b80
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.069216]  r4:c6ead3c0
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.071829] [<bf0fe060>] (ieee80211_tasklet_handler [mac80211]) from [<c001a150>] (tasklet_action+0x90/0xd4)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.081720]  r7:c0575e10 r6:c7311c24 r5:00000000 r4:c05579b4
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.087425] [<c001a0c0>] (tasklet_action) from [<c00199a8>] (__do_softirq+0xe4/0x230)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.095288]  r7:c0575e10 r6:00000006 r5:00000024 r4:40000002
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.100994] [<c00198c4>] (__do_softirq) from [<c0019b20>] (run_ksoftirqd+0x2c/0x5c)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.108699]  r10:00000000 r9:00000000 r8:00000001 r7:00000000 r6:c05579c8 r5:c7840000
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.116575]  r4:c7805f20
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.119128] [<c0019af4>] (run_ksoftirqd) from [<c0031bf4>] (smpboot_thread_fn+0x14c/0x160)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.127453] [<c0031aa8>] (smpboot_thread_fn) from [<c002e7d0>] (kthread+0xd8/0xec)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.135063]  r9:00000000 r8:00000000 r7:c0031aa8 r6:c7805f20 r5:00000000 r4:c7805f40
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.142857] [<c002e6f8>] (kthread) from [<c000a2e8>] (ret_from_fork+0x14/0x2c)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.150125]  r7:00000000 r6:00000000 r5:c002e6f8 r4:c7805f40
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.155822] ---[ end trace 7a627567bca50b74 ]---
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.160459] ------------[ cut here ]------------
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.165167] WARNING: CPU: 0 PID: 3 at backports-2017-11-01/net/mac80211/rx.c:4362 ieee80211_rx_napi+0x8c/0x87c [mac80211]
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.176187] Modules linked in: pppoe ppp_async pppox ppp_generic nf_conntrack_ipv6 mwl8k 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_CT slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables x_tables
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.230150] CPU: 0 PID: 3 Comm: ksoftirqd/0 Tainted: G        W       4.9.86 #0
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.237503] Hardware name: Marvell Kirkwood (Flattened Device Tree)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.243792] Backtrace:
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.246271] [<c000d204>] (dump_backtrace) from [<c000d4c8>] (show_stack+0x18/0x1c)
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.253878]  r7:bf11fda0 r6:00000000 r5:bf15223a r4:00000000
Sat Mar 10 15:57:36 2018 kern.warn kernel: [  745.259584] [<c000d4b0>] (show_stack) from [

I have the problem too. I found a similar question on

also
https://patchwork.kernel.org/patch/9764917/
at last ๏ผŒthe problem seems sloved use this patch

diff -Nur a/net/mac80211/rx.c b/net/mac80211/rx.c
--- a/net/mac80211/rx.c	2018-05-05 17:54:02.303444000 +0800
+++ b/net/mac80211/rx.c	2018-05-05 18:08:39.375412654 +0800
@@ -4359,7 +4359,7 @@
 			WARN_ON_ONCE(1);
 			/* fall through */
 		case RX_ENC_LEGACY:
-			if (WARN_ON(status->rate_idx >= sband->n_bitrates))
+			if ((status->rate_idx >= sband->n_bitrates))
 				goto drop;
 			rate = &sband->bitrates[status->rate_idx];
 		}

if you can not compile the firmware youself,according to (SOLVED) Linksys EA3500 5G is not usable ,just edit the system config file's two line
/etc/config/system

config system
	option conloglevel '1'
	option klogconloglevel '1'

after reboot,the load average will reduce but the warning still appera in dmesg