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    SubjectRe: [Slub allocator] There are chances that kmem_cache_cpu->freelist gets lost if the process happens to be rescheduled to a differenet cpu before the local_irq_save() completes in __slab_alloc()
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    Le lundi 12 décembre 2011 à 12:53 -0600, Christoph Lameter a écrit :
    > On Mon, 12 Dec 2011, Eric Dumazet wrote:
    >
    > > Indeed, I reproduced the leak with hackbench and lot of threads.
    >
    > Ran it here and did not see anything. But obviously this is an issue.
    > Strange that no one noticed earlier. Usage of CONFIG_PREEMPT must not be
    > that frequent.
    >

    Yes, probably :(

    All I did was using hackbench with 4000 threads on my 16 cpu machine,

    while :; do hackbench 100 process 2000 ; done

    I got about one leak (freelist chain, so several objects leaked) per
    second.



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