Frequent Connection drops with Qualcomm Atheros, in desparate need of help [SOLVED]

Issues related to configuring your network
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snowball
Posts: 5
Joined: 2020/08/21 16:57:07

Frequent Connection drops with Qualcomm Atheros, in desparate need of help [SOLVED]

Post by snowball » 2020/08/21 17:33:02

Hi,

I am having issues with my new CentOS 8 install (minimal) dropping network connections. The issue seems to affect both wireless and wired. I am not an expert in CentOS/Linux. I heavily use/rely on it as a software developer. At first I thought it was because of system idle/power settings, but it happens sometime back-to-back within few minutes. I desperately need and would really appreciate some help.

I installed a CentOS 8 on a new Del XPS 8930 (with GNOME at first, then just minimal). In both versions, the Qualcomm adapters (QCA9377 and Killer E2400) connect just fine but after a point the connections to one or both are dropped. Here are a few things I tried reading online docs -
  • NetworkManager-wifi install,
  • Editing power saving mode for the connections,
  • Masking sleep, suspend hibernate,
  • Bonding the two network connections for fault tolerance,
  • Going from GNOME to minimal install
  • Setting up connections via gnome, nmtui vs. nmcli commands

I didn't try driver re-installs or testing with difference hardware (which I don't have).

When connections are lost, ping fails to other network/internet IPs/domains. But nmcli status shows as though the connections are active. Example:

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[root@peaches styles]# nmcli dev status
DEVICE          TYPE      STATE         CONNECTION
enp4s0          ethernet  connected     enp4s0
wlp3s0          wifi      connected     wifi_ssid
lo              loopback  unmanaged     --

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[root@peaches styles]# ip addr show
...
2: enp4s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether <mac_addr_masked> brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.114/24 brd 192.168.1.255 scope global noprefixroute enp4s0
       valid_lft forever preferred_lft forever
    inet6 fe80::ebe5:56b5:95fc:dd7/64 scope link noprefixroute
       valid_lft forever preferred_lft forever
3: wlp3s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether <mac_addr_masked> brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.114/24 brd 192.168.1.255 scope global dynamic noprefixroute wlp3s0
       valid_lft 82293sec preferred_lft 82293sec
    inet6 fe80::7f5b:388f:39e2:1089/64 scope link noprefixroute
       valid_lft forever preferred_lft forever
NetworkManager status (systemctl -l status NetworkManager) shows active and running.

Once connection is lost, I used "nmcli c up wifi_ssid" or "nmcli c up enp4s0" to manually bring it backup. Later, I created a cronjob to check ping results and perform the same command on ping failure - as a temporary workaround.

Here are some info from the system. I can provide more as needed.

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[root@peaches styles]# uname -a
Linux peaches 4.18.0-193.14.2.el8_2.x86_64 #1 SMP Sun Jul 26 03:54:29 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

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[root@peaches styles]# lspci -k
...
03:00.0 Network controller: Qualcomm Atheros QCA9377 802.11ac Wireless Network Adapter (rev 31)
	Subsystem: Dell Device 1810
	Kernel driver in use: ath10k_pci
	Kernel modules: ath10k_pci
04:00.0 Ethernet controller: Qualcomm Atheros Killer E2400 Gigabit Ethernet Controller (rev 10)
	Subsystem: Dell Device 0859
	Kernel driver in use: alx
	Kernel modules: alx

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[root@peaches styles]# ls -al /lib/firmware/ath10k/QCA9377/hw1.0/
total 1812
drwxr-xr-x. 2 root root     86 Aug 16 20:49 .
drwxr-xr-x. 3 root root     19 Aug 16 20:49 ..
-rw-r--r--. 1 root root 304308 Jan 10  2020 board-2.bin
-rw-r--r--. 1 root root   8124 Jan 10  2020 board.bin
-rw-r--r--. 1 root root 783336 Jan 10  2020 firmware-5.bin
-rw-r--r--. 1 root root 751436 Jan 10  2020 firmware-6.bin

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[root@peaches styles]# dmesg | grep -i ath
[    2.665582] alx 0000:04:00.0 eth0: Qualcomm Atheros AR816x/AR817x Ethernet [5c:3a:45:be:7c:7f]
[   13.805959] ath10k_pci 0000:03:00.0: enabling device (0000 -> 0002)
[   13.807560] ath10k_pci 0000:03:00.0: pci irq msi oper_irq_mode 2 irq_mode 0 reset_mode 0
[   14.847258] ath10k_pci 0000:03:00.0: qca9377 hw1.1 target 0x05020001 chip_id 0x003821ff sub 1028:1810
[   14.847259] ath10k_pci 0000:03:00.0: kconfig debug 0 debugfs 1 tracing 0 dfs 0 testmode 0
[   14.847548] ath10k_pci 0000:03:00.0: firmware ver WLAN.TF.2.1-00021-QCARMSWP-1 api 6 features wowlan,ignore-otp crc32 42e41877
[   14.940679] ath10k_pci 0000:03:00.0: board_file api 2 bmi_id N/A crc32 8aedfa4a
[   15.015390] ath10k_pci 0000:03:00.0: unsupported HTC service id: 1536
[   15.034402] ath10k_pci 0000:03:00.0: htt-ver 3.56 wmi-op 4 htt-op 3 cal otp max-sta 32 raw 0 hwcrypto 1
[   15.093215] ath: EEPROM regdomain: 0x6c
[   15.093215] ath: EEPROM indicates we should expect a direct regpair map
[   15.093216] ath: Country alpha2 being used: 00
[   15.093217] ath: Regpair used: 0x6c
[   15.123100] ath10k_pci 0000:03:00.0 wlp3s0: renamed from wlan0
[   29.714339] ath10k_pci 0000:03:00.0: unsupported HTC service id: 1536
[   29.999847] ath10k_pci 0000:03:00.0: unsupported HTC service id: 1536
[ 2065.511271] ath10k_pci 0000:03:00.0: failed to flush transmit queue (skip 0 ar-state 1): 0
[ 2373.732314] ath10k_pci 0000:03:00.0: failed to flush transmit queue (skip 0 ar-state 1): 0
[ 2490.467169] ath10k_pci 0000:03:00.0: failed to flush transmit queue (skip 0 ar-state 1): 0
[ 2613.857659] ath10k_pci 0000:03:00.0: failed to flush transmit queue (skip 0 ar-state 1): 0
[ 3030.109384] ath10k_pci 0000:03:00.0: failed to flush transmit queue (skip 0 ar-state 1): 0
[ 3393.625826] ath10k_pci 0000:03:00.0: failed to flush transmit queue (skip 0 ar-state 1): 0
[ 3574.360227] ath10k_pci 0000:03:00.0: failed to flush transmit queue (skip 0 ar-state 1): 0
[ 4769.868435] ath10k_pci 0000:03:00.0: failed to flush transmit queue (skip 0 ar-state 1): 0
[ 6514.236465] ath10k_pci 0000:03:00.0: failed to flush transmit queue (skip 0 ar-state 1): 0
Last edited by snowball on 2020/08/28 17:56:13, edited 1 time in total.

snowball
Posts: 5
Joined: 2020/08/21 16:57:07

Re: Frequent Connection drops with Qualcomm Atheros, in desparate need of help

Post by snowball » 2020/08/24 15:12:37

I wanted to add a comment with some additional observations. It is possible that the issue is primarily with WIFI - not wired. When I created a bond with the two connections, all network/internet connections would seem to drop at random times. I tried several different bond modes, round-robin, active-backup and broadcast, with the same result. But when it is not in a bond, it is only the wifi connection that's dropping. The wired connection stays on. From this, I have a feeling that the bond connection was dropped due to the wifi failure, even though I was hoping for fault tolerance from those modes.

I still need to resolve the issue with wifi dropping connections since my wired connection is not good. It is connected through a previously existing LAN outlet(s) built into my walls of my house, which for whatever reasons provide very poor connection speed - no matter the target device.

BShT
Posts: 278
Joined: 2019/10/09 12:31:40

Re: Frequent Connection drops with Qualcomm Atheros, in desparate need of help

Post by BShT » 2020/08/24 16:56:13

look at your router and see what country is there, set to USA or set a static channel

there are channels and some drivers only works from 1 to 11

here in my country channel 1 to 13 are allowed but most of linuxes drivers cant connect with channel 12 and 13

snowball
Posts: 5
Joined: 2020/08/21 16:57:07

Re: Frequent Connection drops with Qualcomm Atheros, in desparate need of help

Post by snowball » 2020/08/24 18:05:49

Thank you for the reply. I have the 2.4GHz manually set to channel 05 and the 5GHz is set to channel 161 for a while now. The drop occurs on both 2.4 and 5.

snowball
Posts: 5
Joined: 2020/08/21 16:57:07

Re: Frequent Connection drops with Qualcomm Atheros, in desparate need of help

Post by snowball » 2020/08/26 18:08:14

I finally found what I believe is a good reason for the unstable wifi connection. Pouring through the system log for the firmware ath10k, I found notices for firmware crash -

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ath10k_pci 0000:03:00.0: firmware crashed! (guid efc9c09b-a909-4431-b438-683b8dedffd2)
ath10k_pci 0000:03:00.0: firmware register dump:
ath10k_pci 0000:03:00.0: [00]: 0x05020001 0x00000000 0x809E1F2B 0x00000044
ath10k_pci 0000:03:00.0: [04]: 0x809E1F2B 0x0040E9B8 0x00000000 0x00180207
ath10k_pci 0000:03:00.0: [08]: 0xDEADC0DE 0x0000000C 0x00000023 0x00431664
ath10k_pci 0000:03:00.0: [12]: 0x809FA4B5 0x0040E9A8 0xAA0A10CB 0x00018200
ath10k_pci 0000:03:00.0: [16]: 0x0042A080 0x0042A0E8 0x00000018 0x00000001
ath10k_pci 0000:03:00.0: [20]: 0x8093853B 0x0040E988 0x0001810C 0x00000000
ath10k_pci 0000:03:00.0: [24]: 0xFFFFFFDF 0x00080200 0x00407C40 0x00400000
ath10k_pci 0000:03:00.0: [28]: 0x809FAF2D 0x0040E9E8 0x00000000 0x00000001
ath10k_pci 0000:03:00.0: [32]: 0x00407E84 0x00429D60 0x00000003 0x00180207
ath10k_pci 0000:03:00.0: [36]: 0x00000000 0x00000000 0x00000000 0x00000000
ath10k_pci 0000:03:00.0: [40]: 0x00000000 0x00000000 0x00000000 0x00000000
ath10k_pci 0000:03:00.0: [44]: 0x00000000 0x00000000 0x00000000 0x00000000
ath10k_pci 0000:03:00.0: [48]: 0x00000000 0x00000000 0x00000000 0x00000000
ath10k_pci 0000:03:00.0: [52]: 0x00000000 0x00000000 0x00000000 0x00000000
ath10k_pci 0000:03:00.0: [56]: 0x00000000 0x00000000 0x00000000 0x00000000
At this time, I have no idea what this means and how to resolve this. If anyone could provide some guidance, I'd greatly appreciate.

I will continue to research and if I find a solution, I will update this thread with new posts, in-case it helps the next person with a similar issue.

snowball
Posts: 5
Joined: 2020/08/21 16:57:07

Re: Frequent Connection drops with Qualcomm Atheros, in desparate need of help [SOLVED]

Post by snowball » 2020/08/28 18:11:49

SOLVED: :)

After seeing the error message from the logs about the firmware (see last post), I tried to find firmware replacements. Following forum posts helped -

https://www.linuxquestions.org/question ... ost6039859
https://forums.gentoo.org/viewtopic-t-1 ... art-0.html
http://manjaro.moson.eu/pool/overlay/ (there are some other sources as well)

Steps -
1. Downloaded the latest firmware - dated 2020-08-17
2. Extract it
3. Back up the existing Qualcomm QCA9377 drivers from "/lib/firmware/ath10k/QCA9377"
4. Replace the directory "/lib/firmware/ath10k/QCA9377" with the "QCA9377" directory from the download
5. Reboot machine.

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wget http://manjaro.moson.eu/pool/overlay/linux-firmware-20200817.r1695.7a30af1-1-any.pkg.tar.zst
tar -I zstd -xvf linux-firmware-20200817.r1695.7a30af1-1-any.pkg.tar.zst

mkdir ~/firmware_bak
mv /lib/firmware/ath10k/QCA9377 ./firmware_bak/
cp -r ./usr/lib/firmware/ath10k/QCA9377 /lib/firmware/ath10k/
reboot now
The wifi has been stable for 48 hours by the time this post was made.

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