• Lee Schermerhorn's avatar
    mempolicy: fixup Fallback for Default Shmem Policy · ae4d8c16
    Lee Schermerhorn authored
    get_vma_policy() is not handling fallback to task policy correctly when the
    get_policy() vm_op returns NULL.  The NULL overwrites the 'pol' variable that
    was holding the fallback task mempolicy.  So, it was falling back directly to
    system default policy.
    
    Fix get_vma_policy() to use only non-NULL policy returned from the vma
    get_policy op.
    
    shm_get_policy() was falling back to current task's mempolicy if the "backing
    file system" [tmpfs vs hugetlbfs] does not support the get_policy vm_op and
    the vma policy is null.  This is incorrect for show_numa_maps() which is
    likely querying the numa_maps of some task other than current.  Remove this
    fallback.
    Signed-off-by: default avatarLee Schermerhorn <lee.schermerhorn@hp.com>
    Cc: Christoph Lameter <clameter@sgi.com>
    Cc: David Rientjes <rientjes@google.com>
    Cc: Mel Gorman <mel@csn.ul.ie>
    Cc: Andi Kleen <ak@suse.de>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    ae4d8c16
mempolicy.c 54.4 KB