The new function is a reverse operation of set_hwpoison_free_buddy_page()
to adjust unpoison_memory() to the new semantics.
Signed-off-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
---
include/linux/page-flags.h | 8 +++++++-
mm/memory-failure.c | 5 +++--
mm/page_alloc.c | 21 +++++++++++++++++++++
3 files changed, 31 insertions(+), 3 deletions(-)
diff --git v4.19-mmotm-2018-10-30-16-08/include/linux/page-flags.h v4.19-mmotm-2018-10-30-16-08_patched/include/linux/page-flags.h
index 50ce1bd..ab0bde0 100644
--- v4.19-mmotm-2018-10-30-16-08/include/linux/page-flags.h
+++ v4.19-mmotm-2018-10-30-16-08_patched/include/linux/page-flags.h
@@ -382,11 +382,17 @@ PAGEFLAG(HWPoison, hwpoison, PF_ANY)
TESTSCFLAG(HWPoison, hwpoison, PF_ANY)
#define __PG_HWPOISON (1UL << PG_hwpoison)
extern bool set_hwpoison_free_buddy_page(struct page *page);
+extern bool clear_hwpoison_free_buddy_page(struct page *page);
#else
PAGEFLAG_FALSE(HWPoison)
static inline bool set_hwpoison_free_buddy_page(struct page *page)
{
- return 0;
+ return false;
+}
+
+static inline bool clear_hwpoison_free_buddy_page(struct page *page)
+{
+ return false;
}
#define __PG_HWPOISON 0
#endif
diff --git v4.19-mmotm-2018-10-30-16-08/mm/memory-failure.c v4.19-mmotm-2018-10-30-16-08_patched/mm/memory-failure.c
index af541141..a0e1cd4 100644
--- v4.19-mmotm-2018-10-30-16-08/mm/memory-failure.c
+++ v4.19-mmotm-2018-10-30-16-08_patched/mm/memory-failure.c
@@ -1590,8 +1590,9 @@ int unpoison_memory(unsigned long pfn)
}
if (!get_hwpoison_page(p)) {
- if (TestClearPageHWPoison(p))
- num_poisoned_pages_dec();
+ if (!clear_hwpoison_free_buddy_page(p))
+ return 0;
+ num_poisoned_pages_dec();
unpoison_pr_info("Unpoison: Software-unpoisoned free page %#lx\n",
pfn, &unpoison_rs);
return 0;
diff --git v4.19-mmotm-2018-10-30-16-08/mm/page_alloc.c v4.19-mmotm-2018-10-30-16-08_patched/mm/page_alloc.c
index 27826b3..9a90f93 100644
--- v4.19-mmotm-2018-10-30-16-08/mm/page_alloc.c
+++ v4.19-mmotm-2018-10-30-16-08_patched/mm/page_alloc.c
@@ -8270,4 +8270,25 @@ bool set_hwpoison_free_buddy_page(struct page *page)
return hwpoisoned;
}
+
+/*
+ * Reverse operation of set_hwpoison_free_buddy_page(), which is expected
+ * to work only on error pages isolated from buddy allocator.
+ */
+bool clear_hwpoison_free_buddy_page(struct page *page)
+{
+ struct zone *zone = page_zone(page);
+ bool unpoisoned = false;
+
+ spin_lock(&zone->lock);
+ if (TestClearPageHWPoison(page)) {
+ unsigned long pfn = page_to_pfn(page);
+ int migratetype = get_pfnblock_migratetype(page, pfn);
+
+ __free_one_page(page, pfn, zone, 0, migratetype);
+ unpoisoned = true;
+ }
+ spin_unlock(&zone->lock);
+ return unpoisoned;
+}
#endif
--
2.7.0
