[lkml]   [2008]   [Oct]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    Patch in this message
    SubjectRe: [PATCH -tip/cpus4096-v2] cpumask: fix cpumask of call function data
    On Tuesday 28 October 2008 10:07:26 Hiroshi Shimamoto wrote:
    > So, kmalloc(8, flags) for cpumask_var_t at alloc_cpumask_var().
    > But the content is treated as cpumask_t, it causes slab corruption
    > with overwritten when the mask data is copied.

    Yes. This is another one.

    Ingo, please fold.

    Subject: Fix slab corruption when using CONFIG_CPUMASK_OFFSTACK

    Found by Hiroshi Shimamoto; using assignment on a cpumask_t causes slab
    corruption, as we do not allocate sizeof(struct cpumask).

    It looks like we will have to stick with allocating all NR_CPUS bits until the
    end of the patchset (in the future) where we have eliminated all the
    cpumask_t assignments.

    (Note: this ban will be enforced by compiler when we get rid of the 'struct
    cpumask' definition, which is what we're slowly working towards).

    Signed-off-by: Rusty Russell <>

    diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
    index d1f22ee..004da56 100644
    --- a/include/linux/cpumask.h
    +++ b/include/linux/cpumask.h
    @@ -182,7 +182,8 @@ int cpumask_any_but(const struct cpumask *mask, unsigned int cpu);

    static inline size_t cpumask_size(void)
    - return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long);
    + /* FIXME: Use nr_cpumask_bits once all cpumask_t assignments banished */
    + return BITS_TO_LONGS(NR_CPUS) * sizeof(long);

    /* Deprecated. */

     \ /
      Last update: 2008-10-28 01:49    [W:0.021 / U:3.088 seconds]
    ©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site