1. 05 May, 2011 1 commit
    • Linus Torvalds's avatar
      VM: skip the stack guard page lookup in get_user_pages only for mlock · a1fde08c
      Linus Torvalds authored
      The logic in __get_user_pages() used to skip the stack guard page lookup
      whenever the caller wasn't interested in seeing what the actual page
      was.  But Michel Lespinasse points out that there are cases where we
      don't care about the physical page itself (so 'pages' may be NULL), but
      do want to make sure a page is mapped into the virtual address space.
      
      So using the existence of the "pages" array as an indication of whether
      to look up the guard page or not isn't actually so great, and we really
      should just use the FOLL_MLOCK bit.  But because that bit was only set
      for the VM_LOCKED case (and not all vma's necessarily have it, even for
      mlock()), we couldn't do that originally.
      
      Fix that by moving the VM_LOCKED check deeper into the call-chain, which
      actually simplifies many things.  Now mlock() gets simpler, and we can
      also check for FOLL_MLOCK in __get_user_pages() and the code ends up
      much more straightforward.
      Reported-and-reviewed-by: default avatarMichel Lespinasse <walken@google.com>
      Cc: stable@kernel.org
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      a1fde08c
  2. 04 May, 2011 13 commits
  3. 03 May, 2011 16 commits
  4. 02 May, 2011 10 commits