Re: [RFC][PATCH 1/2] x86: Allow breakpoints to emulate call functions

[Steven Rostedt]

On Tue, 7 May 2019 11:27:31 +0200
Peter Zijlstra <peterz@xxxxxxxxxxxxx> 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