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    SubjectRe: perf: fuzzer crashes immediately on AMD system
    On Mon, Aug 22, 2016 at 10:54:32PM -0400, Vince Weaver wrote:
    > > > > >
    > > > > > perf stat -a -e amd_nb/config=0x37,config1=0x20/ /bin/ls
    > > amd_uncore_find_online_sibling()
    > > function is broken.
    >
    > and that's the problem. uncore_find_online_sibling() does all kinds of
    > wrong things including sticking active uncore structures in
    > uncore->free_when_cpu_online
    >
    > Then uncore_online() comes along and frees those structures.
    >
    > Then some other part of the kernel comes and re-uses the free'd data.
    >
    > Then when we try to start an event, all of the fields are invalid because
    > the uncore pointer is pointing to re-used data.
    >
    > I don't have a patch because I am not 100% clear on what
    > uncore_find_online_sibling() is doing in the first place.

    Thanks for doing all that, I'll see if I can make sense of it.

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