(SOLVED) Linksys EA3500 5G is not usable

Not sure anyone has seen similar issue on 5G WiFi. I basically am using 17.01.4 but compiled by myself. Before I tried Openwrt trunk but the behavior is same.
Once 5G enabled, the router becomes very slow.

Below msg is printed out repeatedly.

> Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.225995] ------------[ cut here ]------------
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.230736] WARNING: CPU: 0 PID: 3 at compat-wireless-2017-01-31/net/mac80211/rx.c:4224 ieee80211_rx_napi+0x184/0x900 [mac80211]()
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.242552] Modules linked in: pppoe ppp_async iptable_nat pppox ppp_generic nf_nat_ipv4 nf_conntrack_ipv6 nf_conntrack_ipv4 mwl8k mac80211 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 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 nf_conntrack iptable_mangle iptable_fMon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.296032] CPU: 0 PID: 3 Comm: ksoftirqd/0 Tainted: G        W       4.4.93 #0
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.303377] Hardware name: Marvell Kirkwood (Flattened Device Tree)
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.309689] Backtrace:
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.312175] [<c0015dd0>] (dump_backtrace) from [<c0015fd8>] (show_stack+0x18/0x1c)
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.319800]  r7:bf157728 r6:bf121e5c r5:00001080 r4:00000000
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.325550] [<c0015fc0>] (show_stack) from [<c01c4b20>] (dump_stack+0x20/0x28)
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.332819] [<c01c4b00>] (dump_stack) from [<c001df84>] (warn_slowpath_common+0x94/0xbc)
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.340978] [<c001def0>] (warn_slowpath_common) from [<c001e050>] (warn_slowpath_null+0x24/0x2c)
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.349820]  r8:00000000 r7:00000000 r6:c33d0b40 r5:c2f9da80 r4:c33d0b40
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.356710] [<c001e02c>] (warn_slowpath_null) from [<bf121e5c>] (ieee80211_rx_napi+0x184/0x900 [mac80211])
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.366593] [<bf121cd8>] (ieee80211_rx_napi [mac80211]) from [<bf0fd0bc>] (ieee80211_tasklet_handler+0x5c/0xb8 [mac80211])
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.377712]  r10:00000004 r9:00000100 r8:c383a000 r7:c33d0f70 r6:c33d0b40 r5:c33d0f64
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.385634]  r4:c2f9da80
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.388278] [<bf0fd060>] (ieee80211_tasklet_handler [mac80211]) from [<c00205b4>] (tasklet_action+0x88/0xd8)
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.398168]  r7:00000000 r6:c05aef80 r5:c0590b04 r4:c33d1be4
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.403895] [<c002052c>] (tasklet_action) from [<c002083c>] (__do_softirq+0xac/0x240)
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.411777]  r7:40000003 r6:c05aef54 r5:c05aef60 r4:00000006
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.417524] [<c0020790>] (__do_softirq) from [<c00209fc>] (run_ksoftirqd+0x2c/0x5c)
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.425232]  r10:00000000 r9:00000002 r8:c05955bc r7:00000001 r6:00000000 r5:c383a000
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.433138]  r4:c3805cc0
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.435716] [<c00209d0>] (run_ksoftirqd) from [<c0037da0>] (smpboot_thread_fn+0x158/0x16c)
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.444023] [<c0037c48>] (smpboot_thread_fn) from [<c00356c8>] (kthread+0xd4/0xe4)
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.451645]  r9:00000000 r8:00000000 r7:c0037c48 r6:c3805cc0 r5:00000000 r4:c3805ce0
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.459493] [<c00355f4>] (kthread) from [<c0009590>] (ret_from_fork+0x14/0x24)
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.466764]  r7:00000000 r6:00000000 r5:c00355f4 r4:c3805ce0
Mon Oct 30 10:28:32 2017 kern.warn kernel: [ 2764.472485] ---[ end trace d57f6c7e9c672d5e ]---

> Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.813015] ------------[ cut here ]------------
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.817752] WARNING: CPU: 0 PID: 3 at compat-wireless-2017-01-31/net/mac80211/rx.c:4224 ieee80211_rx_napi+0x184/0x900 [mac80211]()
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.829566] Modules linked in: pppoe ppp_async iptable_nat pppox ppp_generic nf_nat_ipv4 nf_conntrack_ipv6 nf_conntrack_ipv4 mwl8k mac80211 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 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 nf_conntrack iptable_mangle iptable_fMon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.883070] CPU: 0 PID: 3 Comm: ksoftirqd/0 Tainted: G        W       4.4.93 #0
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.890415] Hardware name: Marvell Kirkwood (Flattened Device Tree)
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.896728] Backtrace:
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.899213] [<c0015dd0>] (dump_backtrace) from [<c0015fd8>] (show_stack+0x18/0x1c)
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.906836]  r7:bf157728 r6:bf121e5c r5:00001080 r4:00000000
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.912586] [<c0015fc0>] (show_stack) from [<c01c4b20>] (dump_stack+0x20/0x28)
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.919856] [<c01c4b00>] (dump_stack) from [<c001df84>] (warn_slowpath_common+0x94/0xbc)
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.928011] [<c001def0>] (warn_slowpath_common) from [<c001e050>] (warn_slowpath_null+0x24/0x2c)
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.936848]  r8:00000000 r7:00000000 r6:c33d0b40 r5:c2f74a80 r4:c33d0b40
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.943741] [<c001e02c>] (warn_slowpath_null) from [<bf121e5c>] (ieee80211_rx_napi+0x184/0x900 [mac80211])
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.953622] [<bf121cd8>] (ieee80211_rx_napi [mac80211]) from [<bf0fd0bc>] (ieee80211_tasklet_handler+0x5c/0xb8 [mac80211])
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.964739]  r10:00000004 r9:00000100 r8:c383a000 r7:c33d0f70 r6:c33d0b40 r5:c33d0f64
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.972661]  r4:c2f74a80
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.975299] [<bf0fd060>] (ieee80211_tasklet_handler [mac80211]) from [<c00205b4>] (tasklet_action+0x88/0xd8)
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.985196]  r7:00000000 r6:c05aef80 r5:c0590b04 r4:c0593458
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.990942] [<c002052c>] (tasklet_action) from [<c002083c>] (__do_softirq+0xac/0x240)
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3485.998803]  r7:40000002 r6:c05aef58 r5:c05aef60 r4:00000006
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3486.004543] [<c0020790>] (__do_softirq) from [<c00209fc>] (run_ksoftirqd+0x2c/0x5c)
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3486.012250]  r10:00000000 r9:00000002 r8:c05955bc r7:00000001 r6:00000000 r5:c383a000
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3486.020158]  r4:c3805cc0
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3486.022735] [<c00209d0>] (run_ksoftirqd) from [<c0037da0>] (smpboot_thread_fn+0x158/0x16c)
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3486.031063] [<c0037c48>] (smpboot_thread_fn) from [<c00356c8>] (kthread+0xd4/0xe4)
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3486.038663]  r9:00000000 r8:00000000 r7:c0037c48 r6:c3805cc0 r5:00000000 r4:c3805ce0
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3486.046504] [<c00355f4>] (kthread) from [<c0009590>] (ret_from_fork+0x14/0x24)
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3486.053775]  r7:00000000 r6:00000000 r5:c00355f4 r4:c3805ce0
Mon Oct 30 10:40:34 2017 kern.warn kernel: [ 3486.059495] ---[ end trace d57f6c7e9c673245 ]---

Don't anyone see this issue?
Bump it up.

A little early for a bump...

If you are configured to use 802.11b/g/n and WMM is not enabled, the router will fall back to 802.11a/g rates, giving you a slower connection. Same with using TKIP and WPA2.

If that's not it, post your wireless configs.

WMM is enabled as default. Also in Luci I checked it is toggled.

My wireless config is as below. The problem is once enabled wlan1 (5G), more than 90% cpu is occupied by soft irq. So I cannot use 5G not even mention the tput.

=============================================

root@xeon_hub:/etc/config# cat wireless

config wifi-device 'radio0'
option type 'mac80211'
option hwmode '11g'
option path 'mbus/mbus:pcie-controller/pci0000:00/0000:00:01.0/0000:01:00.0'
option htmode 'HT20'
option channel 'auto'
option txpower '17'
option country '00'

config wifi-iface 'default_radio0'
option device 'radio0'
option network 'lan'
option mode 'ap'
option ssid 'hub_2.4'
option encryption 'psk2+ccmp'
option key '1234567890'

config wifi-device 'radio1'
option type 'mac80211'
option hwmode '11a'
option path 'mbus/mbus:pcie-controller/pci0000:00/0000:00:02.0/0000:02:00.0'
option channel 'auto'
option htmode 'HT40'
option txpower '17'
option country '00'

config wifi-iface 'default_radio1'
option device 'radio1'
option network 'lan'
option mode 'ap'
option ssid 'hub_5'
option encryption 'psk2+ccmp'
option key '1234567890'

I probably have figured out the cause. After set the logging level lower than "Warning" (<=4) the problem solved. :poop:


@ximibaba
I meet this issue too,and 2.4G is not stable
I also found it will auto reboot sometime
it make me sad

I don't see unstable WiFi issue on EA3500 now. Are you using stable 17.01 LEDE build? Trunk is not recommended.

try download big file ,play online videos and keep 2 or 3 device connecting in a little far distance,you will find the problem

yes,I tried Trunk,it's bad idea,thanks
I wonder whether the RAM is not enough big in EA3500
I'm thinking buy a EA4500,but it looks they are same one,except flash and rom

especially connect with other WiFi extender as main router ,it will reboot frequently

Maybe I am not using EA3500 under heavy task. One EA3500 is as extender and the other one is used mostly as gigabyte switch. Occasionally I turn on both 2.4G/5G but everything looks fine.
RAM is 64G which should be enough for most routing/bridging scenarios.

For reboot issue, you can check /sys/kernel/debug/crashlog if crashlog still works. To make sure crashlog is working, run
echo c >/proc/sysrq-trigger
Once sure about crashlog. You can wait the reboot issue reproduced and check crashlog after power cycle.

thanks for these useful information !
I will try
talk to you later

thank you @ximibaba

HI @ximibaba
today it auto reboot again
then I do following

root@lede:~# cat /sys/kernel/debug/crashlog
cat: can't open '/sys/kernel/debug/crashlog': No such file or directory
root@lede:~# echo c >/proc/sysrq-trigger

after that it autoreboot

and here are datas of RMA

Total Available 16416 kB / 59856 kB (27%)
Free 12948 kB / 59856 kB (21%)
Buffered 3468 kB / 59856 kB (5%)

do you have any idea

thanks

No crash log means there is no kernel panic. Either there is not a reboot, or HW itself is broken.
It is very hard to help you without valid log or information. :frowning_face:

Below is the snapshot after triggering a kernel panic. crashlog is generated and kept after power cycle.

001

it's ok ,I will test it go on
I love ea3500 and hate it,the speed is faster than netgear 4300 ,but the WiFi is not stable.and if I excute more iptables rule on it ,it will suck or reboot sometime

when I try lede master on it.I found the ping value is high

today I ordered a ea4500 to verify the RAM is ok or not

why do you choise ea3500?
thanks

It is the cheapest one with gigabit Ethernet and dual bands. Besides I am a little bit tired of tp-link.

yes,it's cheap with good performance
I have some mini tp-link model for repeater and printer

by the way ,there are 2 issues
1 is how to use full 64M flash size?
the other is how to enable the reset buttion?

Do you have any ideas,I could not find it on google
thanks

  1. 64M flash has been used.
Flash Layout

The stock layout (of the 64MiB flash chip):
Offset 	Size 	Name
0x0 	0x80000 	uboot
0x80000 	0x4000 	u_env
0x84000 	0x4000 	s_env
0x200000 	0x294000 	kernel
0x494000 	0xf6c000 	rootfs
0x1600000 	0x294000 	alt_kernel
0x1894000 	0xf6c000 	alt_rootfs
0x1600000 	0x2a00000 	syscfg

Note: The marvell uboot has some tweaks that let it dynamically determine where the kernel / alt_kernel end, and automatically adjusts the start point of the rootfs / alt_rootfs accordingly, within a shared allocation of 20MiB.
  1. Install kmod-gpio-button-hotplug