From: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
HWPoisonHandlable() sometimes returns false for typical user pages
due to races with average memory events like transfers over LRU lists.
This causes failures in hwpoison handling.
There's retry code for such a case but does not work because the retry
loop reaches the retry limit too quickly before the page settles down to
handlable state. Let get_any_page() call shake_page() to fix it.
Fixes: 25182f05ffed ("mm,hwpoison: fix race with hugetlb page allocation")
Reported-by: Tony Luck <tony.luck@xxxxxxxxx>
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # 5.13
---
mm/memory-failure.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git v5.14-rc6/mm/memory-failure.c v5.14-rc6_patched/mm/memory-failure.c
index eefd823deb67..aa6592540f17 100644
--- v5.14-rc6/mm/memory-failure.c
+++ v5.14-rc6_patched/mm/memory-failure.c
@@ -1146,7 +1146,7 @@ static int __get_hwpoison_page(struct page *page)
* unexpected races caused by taking a page refcount.
*/
if (!HWPoisonHandlable(head))
- return 0;
+ return -EBUSY;
if (PageTransHuge(head)) {
/*
@@ -1199,9 +1199,14 @@ static int get_any_page(struct page *p, unsigned long flags)
}
goto out;
} else if (ret == -EBUSY) {
- /* We raced with freeing huge page to buddy, retry. */
- if (pass++ < 3)
+ /*
+ * We raced with (possibly temporary) unhandlable
+ * page, retry.
+ */
+ if (pass++ < 3) {
+ shake_page(p, 1);
goto try_again;
+ }
goto out;
}
}
--
2.25.1
