mm/memory-failure: set PageHWPoison before migrate_pages()

Now page freeing code doesn't consider PageHWPoison as a bad page, so by
setting it before completing the page containment, we can prevent the
error page from being reused just after successful page migration.

I added TTU_IGNORE_HWPOISON for try_to_unmap() to make sure that the
page table entry is transformed into migration entry, not to hwpoison
entry.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Dean Nelson <dnelson@redhat.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index cd985530f10239d4118f5170684a8482e810ebc2..ea5a936594887c43506fefe82a61a4ad6fcf4274 100644 (file)
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1659,6 +1659,8 @@ static int __soft_offline_page(struct page *page, int flags)
                inc_zone_page_state(page, NR_ISOLATED_ANON +
                                        page_is_file_cache(page));
                list_add(&page->lru, &pagelist);
+               if (!TestSetPageHWPoison(page))
+                       atomic_long_inc(&num_poisoned_pages);
                ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL,
                                        MIGRATE_SYNC, MR_MEMORY_FAILURE);
                if (ret) {
@@ -1673,9 +1675,8 @@ static int __soft_offline_page(struct page *page, int flags)
                                pfn, ret, page->flags);
                        if (ret > 0)
                                ret = -EIO;
-               } else {
-                       if (!TestSetPageHWPoison(page))
-                               atomic_long_inc(&num_poisoned_pages);
+                       if (TestClearPageHWPoison(page))
+                               atomic_long_dec(&num_poisoned_pages);
                }
        } else {
                pr_info("soft offline: %#lx: isolation failed: %d, page count %d, type %lx\n",

diff --git a/mm/migrate.c b/mm/migrate.c
index f2415be7d93ba80f1b502fad1876221817c0b32c..eb4267107d1fee9fa2a55e4076c014500e3b1edb 100644 (file)
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -880,7 +880,8 @@ static int __unmap_and_move(struct page *page, struct page *newpage,
        /* Establish migration ptes or remove ptes */
        if (page_mapped(page)) {
                try_to_unmap(page,
-                       TTU_MIGRATION|TTU_IGNORE_MLOCK|TTU_IGNORE_ACCESS);
+                       TTU_MIGRATION|TTU_IGNORE_MLOCK|TTU_IGNORE_ACCESS|
+                       TTU_IGNORE_HWPOISON);
                page_was_mapped = 1;
        }