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

[Nathan Royce]

I'm only posting to say I'm still waiting...
The error came up while I slept, and when I copied that log and looked
at it (yes, it WAS huge, just as you said), the timestamps at the
head/tail were much later than the journal logged times.
So I made a little script to monitor the journal kernel entries for
that message and have it copy the file after maybe 5 seconds. And now,
I'm just waiting for that error to occur again.

On Wed, Jan 2, 2019 at 5:32 AM Mathias Nyman
<mathias.nyman@xxxxxxxxxxxxxxx> wrote:
>
> 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