[PATCH 0/3] [GIT PULL][urgent] function-graph: memory leak and race fixes

[Steven Rostedt <rostedt@goodmis.org>]

Ingo,

During testing of the -rt patch, Luis found a bug with the function
profiler (not in 30-rc and I sent the patch for you already), that
he could trigger a crash when enabling and disabling the function
profiler in a loop.

During my investigation of this, I tried enabling and disabling the
function graph tracer in a loop and was able to also crash the kernel.
This crash was not the same as the profiler crash. Looking into this
I found a few problems with the enabling of the function graph tracer.

One was a memory leak, the other two were races on SMP machines.
The races were more likely the cause of the crashes I saw. With these
patches applied, I no longer can produce the crash.

I've also Cc'd the stable team since these bugs also exist in 2.6.29.


Please pull the latest tip/tracing/urgent tree, which can be found at:

  git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace.git
tip/tracing/urgent


Steven Rostedt (3):
      function-graph: only allocate init tasks if it was not already done
      function-graph: enable the stack after initialization of other variables
      function-graph: add memory barriers for accessing task's ret_stack

----
 kernel/trace/ftrace.c                |   23 +++++++++++++++--------
 kernel/trace/trace_functions_graph.c |    6 ++++++
 2 files changed, 21 insertions(+), 8 deletions(-)
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