[PATCH v2 1/3] mm/memory-failure: set has_hwpoisoned flags on HugeTLB folio

[Jiaqi Yan <jiaqiyan@google.com>]

When a free HWPoison HugeTLB folio is dissolved, it becomes
non-HugeTLB and is released to buddy allocator as a high-order
folio.

Set has_hwpoisoned flags on the high-order folio so that buddy
allocator can tell that it contains certain HWPoison page(s).
This is a prepare change for buddy allocator to handle only the
high-order HWPoison folio differently.

This cannot be done with hwpoison flag because users cannot tell
from the case that the page with hwpoison is hardware corrupted.

Signed-off-by: Jiaqi Yan <jiaqiyan@google.com>
---
 include/linux/page-flags.h | 2 +-
 mm/memory-failure.c        | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index f7a0e4af0c734..d13835e265952 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -904,7 +904,7 @@ static inline int PageTransCompound(const struct page *page)
 TESTPAGEFLAG_FALSE(TransCompound, transcompound)
 #endif
 
-#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
+#if defined(CONFIG_MEMORY_FAILURE) && (defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLB_PAGE))
 /*
  * PageHasHWPoisoned indicates that at least one subpage is hwpoisoned in the
  * compound page.
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index fbc5a01260c89..d204de6c9792a 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1952,6 +1952,7 @@ void folio_clear_hugetlb_hwpoison(struct folio *folio)
 	if (folio_test_hugetlb_vmemmap_optimized(folio))
 		return;
 	folio_clear_hwpoison(folio);
+	folio_set_has_hwpoisoned(folio);
 	folio_free_raw_hwp(folio, true);
 }
 
-- 
2.52.0.322.g1dd061c0dc-goog