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SubjectRe: [PATCH 6/9][RFC] kprobes: Allow probe on ftrace reserved text (but move it)
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rostedt wrote:

> [...] Added KPROBE_FLAG_MOVED (as suggested by Masami) that is set
> when the address is moved to get around an ftrace nop. [...]

Steve, perhaps my earlier comments on this got lost during the mailing
list outage.

The gist is that a KPROBE_FLAG_MOVED being set this way accomplishes
very little since nothing is looking for that flag. Instead, you
should patch {arch/*}/kernel/kprobe.c kprobe_handler() to subtract
MCOUNT_INSN_SIZE back out from pt_regs->ip if KPROBE_FLAG_MOVED was
set. That way, kprobes clients need do not perceive the int3 movement.

- FChE


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