Re: kernel: xhci_hcd 0000:00:14.0: ERROR unknown event type 37 - Kernel 4.19.13

[Mathias Nyman]

On 01.01.2019 20:57, Nathan Royce wrote:
> Kernel 4.19.13
>
> 00:14.0 USB controller: Intel Corporation 9 Series Chipset Family USB
> xHCI Controller
>
> Around 400 "unknown event type 37" messages logged in a 2 second span.
> *****
> Jan 01 02:08:07 computername tvheadend[2370]: linuxdvb: Auvitek AU8522
> QAM/8VSB Frontend #0 : ATSC-T #0 - poll TIMEOUT
> Jan 01 02:08:00 computername tvheadend[2370]: linuxdvb: Auvitek AU8522
> QAM/8VSB Frontend #0 : ATSC-T #0 - poll TIMEOUT
> Jan 01 02:07:56 computername kernel: xhci_hcd 0000:00:14.0: ERROR
> unknown event type 37
> ...
> Jan 01 02:07:55 computername kernel: xhci_hcd 0000:00:14.0: ERROR
> unknown event type 37
> Jan 01 02:07:55 computername kernel: xhci_hcd 0000:00:14.0: ERROR
> unknown event type 37
> Jan 01 02:07:52 computername tvheadend[2370]: linuxdvb: Auvitek AU8522
> QAM/8VSB Frontend #0 : ATSC-T #0 - poll TIMEOUT
> Jan 01 02:07:44 computername tvheadend[2370]: linuxdvb: Auvitek AU8522
> QAM/8VSB Frontend #0 : ATSC-T #0 - poll TIMEOUT
> *****
>
> I question whether this also caused kemleak to crash as well (will
> post after this).
>
> Regarding my tv tuner, it isn't supported by the kernel specifically,
> but is close enough that all I have to do is alter a single source
> file to include my device's pid, and it works just fine almost all of
> the time.

The event type 37 is a host controller event, most likely a event ring full error.

So there are probably so many events that we fill the event ring before we can handle them.

Could you take traces of this?
Note that the trace file will be huge.

mount -t debugfs none /sys/kernel/debug
echo 81920 > /sys/kernel/debug/tracing/buffer_size_kb
echo 1 > /sys/kernel/debug/tracing/events/xhci-hcd/enable

copy the traces somewhere safe once the error is triggered:
cp /sys/kernel/debug/tracing/trace  /<somewhere>

-Mathias