tree 50d94ef8c3ffe08b34b9ae3e9993c140733b1a61
parent a093c92dc7f96a15de98ec8cfe38e6f7610a5969
author Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> 1496314095 +0530
committer Michael Ellerman <mpe@ellerman.id.au> 1497606583 +1000

powerpc/kprobes: Pause function_graph tracing during jprobes handling

This fixes a crash when function_graph and jprobes are used together.
This is essentially commit 237d28db036e ("ftrace/jprobes/x86: Fix
conflict between jprobes and function graph tracing"), but for powerpc.

Jprobes breaks function_graph tracing since the jprobe hook needs to use
jprobe_return(), which never returns back to the hook, but instead to
the original jprobe'd function. The solution is to momentarily pause
function_graph tracing before invoking the jprobe hook and re-enable it
when returning back to the original jprobe'd function.

Fixes: 6794c78243bf ("powerpc64: port of the function graph tracer")
Cc: stable@vger.kernel.org # v2.6.30+
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>