On Wed, 8 May 2019 13:30:22 +0900 Masami Hiramatsu mhiramat@kernel.org wrote:
To solve this, an int3_emulate_call() is created for x86_64 to allow ftrace on x86_64 to emulate the call to ftrace_regs_caller() which will make sure all the registered handlers to that function are still called. And this keeps live kernel patching happy!
Out of curiosity, would you have any idea to re-use these function for other use-case? Maybe kprobes can reuse it, but very limited use-case.
Yes, but only for x86_64.
To mimimize the changes, and to avoid controversial patches, this only changes x86_64. Due to the way x86_32 implements the regs->sp the complexity of emulating calls on that platform is too much for stable patches, and live kernel patching does not support x86_32 anyway.
This series looks good to me.
Reviewed-by: Masami Hiramatsu mhiramat@kernel.org
Thanks Masami!
-- Steve