Re: perf, kprobes: fuzzer generates huge number of WARNings

From: Vince Weaver
Date: Mon Jul 06 2015 - 23:47:43 EST


On Mon, 6 Jul 2015, Steven Rostedt wrote:

> On Mon, 6 Jul 2015 17:27:04 -0400 (EDT)
> Vince Weaver <vincent.weaver@xxxxxxxxx> wrote:
> > [ 3521.650521] ---[ end trace a413501925547ed5 ]---
> > [ 3521.655960] ftrace failed to modify [<ffffffff81196730>] handle_mm_fault+0x0/0x1750
> > [ 3521.664767] actual: e8:cb:18:ef:1e
>
> Hmm, it was not expecting to see this address above in the mcount slot.
> Did you have other tracing going on, or did you add a kprobe to
> handle_mm_fault too?

it's fuzzing so there were potentially a large number of tracepoint events
active at the time. Only one kprobe event,
p:probe/VMW _text+1664816
and I forget what that actually mapped to originally.

Vince
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