Re: [PATCH v5 06/15] ftrace: Use an opaque type for functions not callable from C

[Kees Cook]

On Wed, Oct 13, 2021 at 11:16:49AM -0700, Sami Tolvanen wrote:
> With CONFIG_CFI_CLANG, the compiler changes function references to
> point to the CFI jump table. As ftrace_call, ftrace_regs_call, and
> mcount_call are not called by C code, but are trampolines injected
> as calls replacing the nops at the start of functions added by the
> compiler, use DECLARE_NOT_CALLED_FROM_C to declare them.
> 
> Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>

Looks right to me...

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

-- 
Kees Cook