Re: Soft lockup in rt2x00usb_work_rxdone()

[Stanislaw Gruszka]

On Tue, Nov 07, 2017 at 11:06:39AM +0100, Richard Genoud wrote:
> > 3 short articles how to configure and use ftrace are here:
> > https://lwn.net/Articles/365835/
> > https://lwn.net/Articles/366796/
> > https://lwn.net/Articles/370423/
> >
> I tried with ftrace, but I don't think there's a way to dump the trace
> when there's a soft lock-up
> (I can't do anything after the unbind, even the heartbeat led stopped blinking).
> I saw the /proc/sys/kernel/ftrace_dump_on_oops file, but there's no
> /proc/sys/kernel/ftrace_dump_on_soft_lock-up file :)

You should configure function trace with rt2x* functions. After that
start tracing, unbind the device, then stop tracing and provide trace
output.

Thanks
Stanislaw