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Date: Wed, 6 Oct 2021 12:58:09 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Sami Tolvanen <samitolvanen@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>, X86 ML <x86@kernel.org>, Kees Cook
 <keescook@chromium.org>, Peter Zijlstra <peterz@infradead.org>, Nathan
 Chancellor <nathan@kernel.org>, Nick Desaulniers <ndesaulniers@google.com>,
 Sedat Dilek <sedat.dilek@gmail.com>, linux-hardening@vger.kernel.org, LKML
 <linux-kernel@vger.kernel.org>, llvm@lists.linux.dev
Subject: Re: [PATCH v4 06/15] ftrace: Use an opaque type for functions not
 callable from C
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On Wed, 6 Oct 2021 09:31:04 -0700
Sami Tolvanen <samitolvanen@google.com> wrote:

> > > On Thu, Sep 30, 2021 at 11:05:22AM -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 from C, use DECLARE_ASM_FUNC_SYMBOL to declare them.  
> >
> > "not called from C" is a bit confusing.  
> 
> Any thoughts on how to make this less confusing?

 "Not called by C code, but injected by the compiler."

?

-- Steve