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author | Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> | 2015-04-07 14:26:47 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-04-07 16:45:33 -0700 |
commit | 6b79c57b92cdd90853002980609af516d14c4f9c (patch) | |
tree | 2b209795920c9311d8638b6f442224e0aa7995a0 | |
parent | ce66b032ad7b838bf376e3b1bb4d8bce1a69ee5c (diff) | |
download | linux-6b79c57b92cdd90853002980609af516d14c4f9c.tar.bz2 |
mm: numa: disable change protection for vma(VM_HUGETLB)
Currently when a process accesses a hugetlb range protected with
PROTNONE, unexpected COWs are triggered, which finally puts the hugetlb
subsystem into a broken/uncontrollable state, where for example
h->resv_huge_pages is subtracted too much and wraps around to a very
large number, and the free hugepage pool is no longer maintainable.
This patch simply stops changing protection for vma(VM_HUGETLB) to fix
the problem. And this also allows us to avoid useless overhead of minor
faults.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Suggested-by: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: David Rientjes <rientjes@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | kernel/sched/fair.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index bcfe32088b37..241213be507c 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2165,8 +2165,10 @@ void task_numa_work(struct callback_head *work) vma = mm->mmap; } for (; vma; vma = vma->vm_next) { - if (!vma_migratable(vma) || !vma_policy_mof(vma)) + if (!vma_migratable(vma) || !vma_policy_mof(vma) || + is_vm_hugetlb_page(vma)) { continue; + } /* * Shared library pages mapped by multiple processes are not |