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Date:   Tue, 7 May 2019 08:27:16 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Andy Lutomirski <luto@amacapital.net>,
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Subject: Re: [RFC][PATCH 1/2] x86: Allow breakpoints to emulate call
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On Tue, 7 May 2019 11:27:31 +0200
Peter Zijlstra <peterz@infradead.org> wrote:

> FWIW, both these trampolines assume a kprobe will not
> int3_emulate_{push/call}(), for both bitnesses.
> 
> But then; I'm thinking kprobes should be inspection only and not modify
> things. So that might just be good enough.

I believe there are kprobe calls that do modify things. Note, they can
modify regs->ip. Kprobes sets the FTRACE_OPS_FL_IPMODIFY flag, thus
they can never be put at the same location that is being live patched.

-- Steve