From: Steven Rostedt Date: Tue, 2 Jun 2009 20:39:48 +0000 (-0400) Subject: function-graph: move initialization of new tasks up in fork X-Git-Tag: v2.6.31-rc1~400^2~1 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f7e8b616ed1cc6f790b82324bce8a2a60295e5c2;p=pandora-kernel.git function-graph: move initialization of new tasks up in fork When the function graph tracer is enabled, all new tasks must allocate a ret_stack to place the return address of functions. This is because the function graph tracer will replace the real return address with a call to the tracing of the exit function. This initialization happens in fork, but it happens too late. If fork fails, then it will call free_task and that calls the freeing of this ret_stack. But before initialization happens, the new (failed) task points to its parents ret_stack. If a fork failure happens during the function trace, it would be catastrophic for the parent. Also, there's no need to call ftrace_graph_exit_task from fork, since it is called by free_task which fork calls on failure. [ Impact: prevent crash during failed fork running function graph tracer ] Signed-off-by: Steven Rostedt --- Reading git-diff-tree failed