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Date: Wed, 4 Apr 2018 09:49:27 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Kees Cook <keescook@chromium.org>, LKML <linux-kernel@vger.kernel.org>,
        "Tobin C. Harding" <me@tobin.cc>,
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        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Petr Mladek <pmladek@suse.com>
Subject: Re: [RFC][PATCH] tracing, printk: Force no hashing when
 trace_printk() is used
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On Tue, Apr 03, 2018 at 05:06:12PM -0400, Steven Rostedt wrote:
> If you are concerned about attack surface, I could make it a bit more
> difficult to tweak by malicious software. What about the patch below?
> It would be much more difficult to modify this knob from an attack
> vector.

Not if you build using clang, because that doesn't support asm-goto and
thus falls back to a simple runtime variable, which is exactly what Kees
didn't want.