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From:   Andy Lutomirski <luto@amacapital.net>
Date:   Fri, 12 Oct 2018 11:21:28 -0700
Message-ID: <CALCETrXn9zKTb9i1LP3qoFcpqZHF34BdkuZ5D3N0uCmRr+VnbA@mail.gmail.com>
Subject: Re: [RFC][PATCH] x86: ptrace: Add function argument access API
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>
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On Fri, Oct 12, 2018 at 9:26 AM Steven Rostedt <rostedt@goodmis.org> wrote:
>
>
> Anyone have any issues with this patch?
>

I'm conceptually okay with it.  That being said,
regs_within_kernel_stack(), which you're indirectly using, is
off-by-a-few.  And updating it to use probe_kernel_read() might be
nice for robustness.

--Andy