kernel crash when probe context_switch function

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kernel crash when probe context_switch function

bibo,mao-2
Hi,

When I run ./testsuite/buildok/six.stp by "stap -gv" command, it
crashed, the script is like this

probe kernel.inline("context_switch") {
  log ("found an inline function")
}

Does there exist some critical code area in kernel code where probe
point can not be put? And such as context_switch, it can not be probed
by trap method of kprobe.

Regards
Bibo,mao
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Re: kernel crash when probe context_switch function

Martin Hunt
See http://sources.redhat.com/bugzilla/show_bug.cgi?id=1564

To be safe in ALL possible places, I'm changing the IO code to simply
write the data to a buffer and set a flag. (This is what oprofile does.)
Once I finish with some buffering changes, I'll get that checked in.
Until then, avoid IO in scheduler functions.

Martin