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Date: Fri, 10 Jun 2022 23:01:00 -0700
From: Kees Cook <keescook@chromium.org>
To: Sami Tolvanen <samitolvanen@google.com>
Cc: linux-kernel@vger.kernel.org, Josh Poimboeuf <jpoimboe@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>, x86@kernel.org,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>, Mark Rutland <mark.rutland@arm.com>,
	Nathan Chancellor <nathan@kernel.org>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Joao Moreira <joao@overdrivepizza.com>,
	Sedat Dilek <sedat.dilek@gmail.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	linux-hardening@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, llvm@lists.linux.dev
Subject: Re: [RFC PATCH v3 07/20] lkdtm: Emit an indirect call for CFI tests
Message-ID: <202206102300.26A43F5D8@keescook>
References: <20220610233513.1798771-1-samitolvanen@google.com>
 <20220610233513.1798771-8-samitolvanen@google.com>
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In-Reply-To: <20220610233513.1798771-8-samitolvanen@google.com>

On Fri, Jun 10, 2022 at 04:35:00PM -0700, Sami Tolvanen wrote:
> Clang can convert the indirect calls in lkdtm_CFI_FORWARD_PROTO into
> direct calls. Move the call into a noinline function that accepts the
> target address as an argument to ensure the compiler actually emits an
> indirect call instead.
> 
> Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

Acked-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook