Comment is partly wrong, this improves it by including the case of split_huge_pmd_address() called by try_to_unmap_one if TTU_SPLIT_HUGE_PMD is set.
Signed-off-by: Andrea Arcangeli <[email protected]> --- mm/huge_memory.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 9086793..1fbe13d 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3031,8 +3031,10 @@ void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address, return; /* - * Caller holds the mmap_sem write mode, so a huge pmd cannot - * materialize from under us. + * Caller holds the mmap_sem write mode or the anon_vma lock, + * so a huge pmd cannot materialize from under us (khugepaged + * holds both the mmap_sem write mode and the anon_vma lock + * write mode). */ __split_huge_pmd(vma, pmd, address, freeze); }
