Freeze using Linux function tracer on Xenomai 2.6

[Radu Rendec]

Hi Everyone,

I know Xenomai 2.6 has been obsolete for a long time now, but I'm stuck
with a legacy environment that I have to support.

Having said that, I enabled the Linux function tracer in the kernel
configuration and I experience a complete system freeze when I try to
activate it. Basically I'm doing this:

  mount debugfs /sys/kernel/debug/ -t debugfs
  echo function > /sys/kernel/debug/tracing/current_tracer

At that point I get a freeze. The system eventually reboots, but after
10 minutes or so - even though no hardware watchdog is enabled.

I'm running Xenomai 2.6.5 on Linux 3.2.102, on a PowerPC e300 (Freescale
MPC8378). Only Busybox init, sshd and a Busybox shell are running at the
time this happens.

Can anyone think of any reason why this might happen or how I can figure
out what goes wrong?

Thanks in advance,
Radu Rendec