Re: [perf] more perf_fuzzer memory corruption

From: Vince Weaver
Date: Thu May 01 2014 - 09:19:22 EST


On Thu, 1 May 2014, Peter Zijlstra wrote:

> On Thu, May 01, 2014 at 12:51:33AM +0200, Thomas Gleixner wrote:
> > And that's the issue which puzzles us. Let's look at what we expect:
> >
> > Now the trace shows a different story:
> >
> > perf_fuzzer-4387 [001] 1802.628659: sys_enter:
> NR 298 (69bb58, 0, ffffffff, 12, 0, 0)
>
> That's a per-cpu event (.pid = -1, .cpu = 12), they don't get inherited,
> so the only thing keeping it alive is the fd the child got. So
> exit_files() killing this thing makes perfect sense.

wait, are you sure? Isn't that pid=0, cpu=-1, group_fd=12?

my machine only has 8 cpus...

Vince
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