• Peter Feiner's avatar
    mm: softdirty: addresses before VMAs in PTE holes aren't softdirty · 87e6d49a
    Peter Feiner authored
    In PTE holes that contain VM_SOFTDIRTY VMAs, unmapped addresses before
    VM_SOFTDIRTY VMAs are reported as softdirty by /proc/pid/pagemap.  This
    bug was introduced in commit 68b5a652 ("mm: softdirty: respect
    VM_SOFTDIRTY in PTE holes").  That commit made /proc/pid/pagemap look at
    VM_SOFTDIRTY in PTE holes but neglected to observe the start of VMAs
    returned by find_vma.
    
    Tested:
      Wrote a selftest that creates a PMD-sized VMA then unmaps the first
      page and asserts that the page is not softdirty. I'm going to send the
      pagemap selftest in a later commit.
    Signed-off-by: default avatarPeter Feiner <pfeiner@google.com>
    Cc: Cyrill Gorcunov <gorcunov@openvz.org>
    Cc: Pavel Emelyanov <xemul@parallels.com>
    Cc: Hugh Dickins <hughd@google.com>
    Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
    Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
    Cc: Jamie Liu <jamieliu@google.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    87e6d49a
task_mmu.c 38.9 KB