• Hugh Dickins's avatar
    [PATCH] mm: unmap_vmas with inner ptlock · 508034a3
    Hugh Dickins authored
    Remove the page_table_lock from around the calls to unmap_vmas, and replace
    the pte_offset_map in zap_pte_range by pte_offset_map_lock: all callers are
    now safe to descend without page_table_lock.
    Don't attempt fancy locking for hugepages, just take page_table_lock in
    unmap_hugepage_range.  Which makes zap_hugepage_range, and the hugetlb test in
    zap_page_range, redundant: unmap_vmas calls unmap_hugepage_range anyway.  Nor
    does unmap_vmas have much use for its mm arg now.
    The tlb_start_vma and tlb_end_vma in unmap_page_range are now called without
    page_table_lock: if they're implemented at all, they typically come down to
    flush_cache_range (usually done outside page_table_lock) and flush_tlb_range
    (which we already audited for the mprotect case).
    Signed-off-by: default avatarHugh Dickins <hugh@veritas.com>
    Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>