[PATCH v2 2/2] mm: soft-offline: exit with failure for non anonymous thp
From: Naoya Horiguchi
Date: Mon Jan 11 2016 - 22:11:07 EST
Currently memory_failure() doesn't handle non anonymous thp case, because we
can hardly expect the error handling to be successful, and it can just hit
some corner case which results in BUG_ON or something severe like that.
This is also the case for soft offline code, so let's make it in the same way.
Orignal code has a MF_COUNT_INCREASED check before put_hwpoison_page(), but
it's unnecessary because get_any_page() is already called when running on
this code, which takes a refcount of the target page regardress of the flag.
So this patch also removes it.
Signed-off-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
---
ChangeLog v1->v2:
- rebased to next-20160111
---
mm/memory-failure.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git next-20160111/mm/memory-failure.c next-20160111_patched/mm/memory-failure.c
index 2015c9a..6a2f290 100644
--- next-20160111/mm/memory-failure.c
+++ next-20160111_patched/mm/memory-failure.c
@@ -1691,16 +1691,16 @@ static int soft_offline_in_use_page(struct page *page, int flags)
if (!PageHuge(page) && PageTransHuge(hpage)) {
lock_page(hpage);
- ret = split_huge_page(hpage);
- unlock_page(hpage);
- if (unlikely(ret || PageTransCompound(page) ||
- !PageAnon(page))) {
- pr_info("soft offline: %#lx: failed to split THP\n",
- page_to_pfn(page));
- if (flags & MF_COUNT_INCREASED)
- put_hwpoison_page(hpage);
+ if (!PageAnon(hpage) || unlikely(split_huge_page(hpage))) {
+ unlock_page(hpage);
+ if (!PageAnon(hpage))
+ pr_info("soft offline: %#lx: non anonymous thp\n", pfn);
+ else
+ pr_info("soft offline: %#lx: thp split failed\n", pfn);
+ put_hwpoison_page(hpage);
return -EBUSY;
}
+ unlock_page(hpage);
get_hwpoison_page(page);
put_hwpoison_page(hpage);
}
--
2.7.0