[PATCH] mm/memory_hotplug: avoid consuming corrupted data when offline pages

[Miaohe Lin <linmiaohe@huawei.com>]

When trying to offline pages, HWPoisoned hugepage is migrated without
checking PageHWPoison first. So corrupted data could be consumed. Fix
it by deferring isolate_huge_page until PageHWPoison is handled.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
---
 mm/memory_hotplug.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 4c6065e5d274..093f85ec5c5c 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1600,11 +1600,9 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
 		folio = page_folio(page);
 		head = &folio->page;
 
-		if (PageHuge(page)) {
+		if (PageHuge(page))
 			pfn = page_to_pfn(head) + compound_nr(head) - 1;
-			isolate_huge_page(head, &source);
-			continue;
-		} else if (PageTransHuge(page))
+		else if (PageTransHuge(page))
 			pfn = page_to_pfn(head) + thp_nr_pages(page) - 1;
 
 		/*
@@ -1622,6 +1620,11 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
 			continue;
 		}
 
+		if (PageHuge(page)) {
+			isolate_huge_page(head, &source);
+			continue;
+		}
+
 		if (!get_page_unless_zero(page))
 			continue;
 		/*
-- 
2.23.0