Currently hwpoison doesn't handle non-anonymous THP, but since v4.8 THP
support for tmpfs and read-only file cache has been added. They could
be offlined by split THP, just like anonymous THP.
Signed-off-by: Yang Shi <shy828301@xxxxxxxxx>
---
mm/memory-failure.c | 21 ++++++++++++---------
1 file changed, 12 insertions(+), 9 deletions(-)
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 3e06cb9d5121..6f72aab8ec4a 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1150,13 +1150,16 @@ static int __get_hwpoison_page(struct page *page)
if (PageTransHuge(head)) {
/*
- * Non anonymous thp exists only in allocation/free time. We
- * can't handle such a case correctly, so let's give it up.
- * This should be better than triggering BUG_ON when kernel
- * tries to touch the "partially handled" page.
+ * We can't handle allocating or freeing THPs, so let's give
+ * it up. This should be better than triggering BUG_ON when
+ * kernel tries to touch the "partially handled" page.
+ *
+ * page->mapping won't be initialized until the page is added
+ * to rmap or page cache. Use this as an indicator for if
+ * this is an instantiated page.
*/
- if (!PageAnon(head)) {
- pr_err("Memory failure: %#lx: non anonymous thp\n",
+ if (!head->mapping) {
+ pr_err("Memory failure: %#lx: non instantiated thp\n",
page_to_pfn(page));
return 0;
}
@@ -1415,12 +1418,12 @@ static int identify_page_state(unsigned long pfn, struct page *p,
static int try_to_split_thp_page(struct page *page, const char *msg)
{
lock_page(page);
- if (!PageAnon(page) || unlikely(split_huge_page(page))) {
+ if (!page->mapping || unlikely(split_huge_page(page))) {
unsigned long pfn = page_to_pfn(page);
unlock_page(page);
- if (!PageAnon(page))
- pr_info("%s: %#lx: non anonymous thp\n", msg, pfn);
+ if (!page->mapping)
+ pr_info("%s: %#lx: not instantiated thp\n", msg, pfn);
else
pr_info("%s: %#lx: thp split failed\n", msg, pfn);
put_page(page);
--
2.26.2
