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Date: Thu, 23 Feb 2017 19:30:02 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: mhiramat@kernel.org
Cc: Borislav Petkov <bp@alien8.de>, linux-kernel@vger.kernel.org,
        Ingo Molnar <mingo@kernel.org>, Thomas Gleixner <tglx@linutronix.de>
Subject: kprobes vs __ex_table[]
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Hi Masami,

I just wondered what would happen if I put a probe on an instruction
that was listed in __ex_table[] or __bug_table[].

And it looks like it will happily do that. It will then run the
instruction out-of-line, and when said instruction traps, the
instruction address will not match the one listed in either __ex_table[]
or __bug_table[] and badness will happen.

If kprobes does indeed not check this, we should probably fix it, if it
does do check this, could you point me to it?