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From:   Sami Tolvanen <samitolvanen@google.com>
Date:   Fri, 1 Nov 2019 13:32:46 -0700
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Subject: Re: [PATCH v3 11/17] arm64: disable function graph tracing with SCS
To:     Kees Cook <keescook@chromium.org>
Cc:     Will Deacon <will@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Dave Martin <Dave.Martin@arm.com>,
        Laura Abbott <labbott@redhat.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Jann Horn <jannh@google.com>,
        Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
        Masahiro Yamada <yamada.masahiro@socionext.com>,
        clang-built-linux <clang-built-linux@googlegroups.com>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
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On Thu, Oct 31, 2019 at 8:58 PM Kees Cook <keescook@chromium.org> wrote:
> IIRC, the argument was to disable these on a per-arch basis instead of
> doing it as a "depends on !SHADOW_CALL_STACK" in the top-level function
> graph tracer Kconfig?

Yes, that's correct.

> (I'm just thinking ahead to doing this again for
> other architectures, though, I guess, there is much more work than just
> that for, say, x86.)

We can always change this later if needed, and possibly figure out how
to make function graph tracing and kretprobes work with SCS.

Sami