Comment 109 for bug 1521173

Dell Inspiron P74G, Kubuntu 19.04 Disco, kernel 5.0.0-13-generic.

I'm affected as well by this bug, with ~50 lines per minute of errors in the syslog.

I noticed only recently the issue on my Kubuntu 18.04 LTS setup (say, this October 2019). Since then I upgraded to 19.04, but with no improvement. My errors in dmesg are of the same form as stated above, with two recurring types of error statuses:

pcieport 0000:00:1c.4: AER: Corrected error received: 0000:00:1c.4
pcieport 0000:00:1c.4: PCIe Bus Error: severity=Corrected, type=Data Link Layer, (Transmitter ID)
pcieport 0000:00:1c.4: device [8086:9d14] error status/mask=00001000/00002000
pcieport 0000:00:1c.4: [12] Timeout

pcieport 0000:00:1c.4: AER: Corrected error received: 0000:00:1c.4
pcieport 0000:00:1c.4: PCIe Bus Error: severity=Corrected, type=Data Link Layer, (Transmitter ID)
pcieport 0000:00:1c.4: device [8086:9d14] error status/mask=00003000/00002000
pcieport 0000:00:1c.4: [12] Timeout

That pcie port is shown to be connected to the Atheros WiFi of the laptop:

+-1c.4-[02]----00.0 Qualcomm Atheros QCA6174 802.11ac Wireless Network Adapter

The output of lshw for it is:

        *-pci:1
             description: PCI bridge
             product: Sunrise Point-LP PCI Express Root Port #5
             vendor: Intel Corporation
             physical id: 1c.4
             bus info: pci@0000:00:1c.4
             version: f1
             width: 32 bits
             clock: 33MHz
             capabilities: pci pciexpress msi pm normal_decode bus_master cap_list
             configuration: driver=pcieport
             resources: irq:123 memory:d5000000-d51fffff
           *-network
                description: Wireless interface
                product: QCA6174 802.11ac Wireless Network Adapter
                vendor: Qualcomm Atheros
                physical id: 0
                bus info: pci@0000:02:00.0
                logical name: wlp2s0
                version: 32
                serial: [edited for privacy]
                width: 64 bits
                clock: 33MHz
                capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
                configuration: broadcast=yes driver=ath10k_pci driverversion=5.0.0-13-generic firmware=RM.4.4.1.c2-00057-QCARMSWP-1 ip=192.168.0.71 latency=0 link=yes multicast=yes wireless=IEEE 802.11
                resources: irq:131 memory:d5000000-d51fffff

I cannot find an APSM disable option in my BIOS setup.

A guy named Dennis E. Mungai digged into the issue last year (link below), and his temporary fix (turning off the report bit for AER Corrected errors) worked for me, without the need to turn off AER for the whole system.

https://gist.github.com/Brainiarc7/3179144393747f35e5155fdbfd675554

I find interesting that for most of us this issue affects laptop WiFi cards from different vendors.