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Date:   Mon, 21 Oct 2019 09:06:58 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc:     Sami Tolvanen <samitolvanen@google.com>,
        Will Deacon <will@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Dave Martin <Dave.Martin@arm.com>,
        Laura Abbott <labbott@redhat.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Nick Desaulniers <ndesaulniers@google.com>,
        clang-built-linux <clang-built-linux@googlegroups.com>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 16/18] arm64: kprobes: fix kprobes without
 CONFIG_KRETPROBES
Message-ID: <201910210905.7494C5C@keescook>
References: <20191018161033.261971-1-samitolvanen@google.com>
 <20191018161033.261971-17-samitolvanen@google.com>
 <CAKv+Gu-88USO+fbjBgj35B4fUQ7A_t9nHO_swyN=T1q1G2wViA@mail.gmail.com>
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On Mon, Oct 21, 2019 at 08:21:48AM +0200, Ard Biesheuvel wrote:
> On Fri, 18 Oct 2019 at 18:11, Sami Tolvanen <samitolvanen@google.com> wrote:
> >
> > This allows CONFIG_KRETPROBES to be disabled without disabling
> > kprobes entirely.
> >
> > Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
> 
> Can we make kretprobes work with the shadow call stack instead?

I've been viewing that as "next steps". This series is the first step:
actually gaining the feature and clearly indicating where future
improvements can live.

-- 
Kees Cook