The patch titled
     madv_free lazytlb fix
has been added to the -mm tree.  Its filename is
     madv_free-lazytlb-fix.patch

*** Remember to use Documentation/SubmitChecklist when testing your code ***

See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this

------------------------------------------------------
Subject: madv_free lazytlb fix
From: Rik van Riel <[EMAIL PROTECTED]>

Jakub found a potential bug, in that I did not use an atomic
operation to clear the page table entries.  I've attached a
new patch which simply uses ptep_test_and_clear_dirty/young
to get rid of the dirty and accessed bits.

It uses the same atomic accesses we use elsewhere in the VM
and the code is a line shorter than before.

Cc: Nick Piggin <[EMAIL PROTECTED]>
Cc: Hugh Dickins <[EMAIL PROTECTED]>
Cc: Peter Zijlstra <[EMAIL PROTECTED]>
Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
---

 mm/memory.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff -puN mm/memory.c~madv_free-lazytlb-fix mm/memory.c
--- a/mm/memory.c~madv_free-lazytlb-fix
+++ a/mm/memory.c
@@ -677,11 +677,14 @@ static unsigned long zap_pte_range(struc
                                                
remove_exclusive_swap_page(page);
                                                unlock_page(page);
                                        }
-                                       ptep_clear_flush_dirty(vma, addr, pte);
-                                       ptep_clear_flush_young(vma, addr, pte);
+                                       ptep_test_and_clear_dirty(vma, addr, 
pte);
+                                       ptep_test_and_clear_young(vma, addr, 
pte);
                                        SetPageLazyFree(page);
                                        if (PageActive(page))
                                                deactivate_tail_page(page);
+                                       /* tlb_remove_page frees it again */
+                                       get_page(page);
+                                       tlb_remove_page(tlb, page);
                                        continue;
                                }
                        }
_

Patches currently in -mm which might be from [EMAIL PROTECTED] are

mm-madvise-avoid-exclusive-mmap_sem.patch
lazy-freeing-of-memory-through-madv_free.patch
lazy-freeing-of-memory-through-madv_free-fix.patch
lazy-freeing-of-memory-through-madv_free-sparc-fix.patch
madv_free-lazytlb-fix.patch
lazy-freeing-of-memory-through-madv_free-vs-mm-madvise-avoid-exclusive-mmap_sem.patch
restore-madv_dontneed-to-its-original-linux-behaviour.patch

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