FAILED: patch "[PATCH] mm: memory-failure: avoid false hwpoison page mapped error" failed to apply to 5.15-stable tree

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x faeb2ff2c1c5cb60ce0da193580b256c941f99ca
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2023081229-culinary-gliding-61fd@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

faeb2ff2c1c5 ("mm: memory-failure: avoid false hwpoison page mapped error info") f29623e4a599 ("mm: memory-failure: fix potential unexpected return value from unpoison_memory()") a6fddef49eef ("mm/memory-failure: convert unpoison_memory() to folios")
9637d7dfb19c ("mm/memory-failure: convert free_raw_hwp_pages() to folios") 2ff6cecee669 ("mm/memory-failure: convert hugetlb_clear_page_hwpoison to folios") bc1cfde19467 ("mm/memory-failure: convert try_memory_failure_hugetlb() to folios") 911565b82853 ("mm/hugetlb: convert destroy_compound_gigantic_page() to folios") e0ff42804233 ("mm/memory-failure.c: cleanup in unpoison_memory")
cb67f4282bf9 ("mm,thp,rmap: simplify compound page mapcount handling")
dad6a5eb5556 ("mm,hugetlb: use folio fields in second tail page")
f074732d599e ("mm/hugetlb_cgroup: convert hugetlb_cgroup_from_page() to folios") a098c977722c ("mm/hugetlb_cgroup: convert __set_hugetlb_cgroup() to folios") 5033091de814 ("mm/hwpoison: introduce per-memory_block hwpoison counter") a46c9304b4bb ("mm/hwpoison: pass pfn to num_poisoned_pages_*()")
d027122d8363 ("mm/hwpoison: move definitions of num_poisoned_pages_* to memory-failure.c") e591ef7d96d6 ("mm,hwpoison,hugetlb,memory_hotplug: hotremove memory section with hwpoisoned hugepage") b66d00dfebe7 ("mm: memory-failure: make action_result() return int")
4781593d5dba ("mm/hugetlb: unify clearing of RestoreReserve for private pages") 149562f75094 ("mm/hugetlb: add hugetlb_folio_subpool() helpers")
d340625f4849 ("mm: add private field of first tail to struct page and struct folio")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From faeb2ff2c1c5cb60ce0da193580b256c941f99ca Mon Sep 17 00:00:00 2001
From: Miaohe Lin <[email protected]>
Date: Thu, 27 Jul 2023 19:56:42 +0800
Subject: [PATCH] mm: memory-failure: avoid false hwpoison page mapped error
info

folio->_mapcount is overloaded in SLAB, so folio_mapped() has to be done after folio_test_slab() is checked. Otherwise slab folio might be treated as a mapped folio leading to false 'Someone maps the hwpoison page' error info.

index b32d370b5d43..9a285038d765 100644
@@ -2499,6 +2499,13 @@ int unpoison_memory(unsigned long pfn)
 		goto unlock_mutex;
 	}
 
+	if (folio_test_slab(folio) || PageTable(&folio->page) || folio_test_reserved(folio))
+		goto unlock_mutex;
+
+	/*
+	 * Note that folio->_mapcount is overloaded in SLAB, so the simple test
+	 * in folio_mapped() has to be done after folio_test_slab() is checked.
+	 */
 	if (folio_mapped(folio)) {
 		unpoison_pr_info("Unpoison: Someone maps the hwpoison page %#lx\n",
 				 pfn, &unpoison_rs);

@@ -2511,9 +2518,6 @@ int unpoison_memory(unsigned long pfn)
 		goto unlock_mutex;
 	}
 
-	if (folio_test_slab(folio) || PageTable(&folio->page) || folio_test_reserved(folio))
-		goto unlock_mutex;
-
 	ghp = get_hwpoison_page(p, MF_UNPOISON);
 	if (!ghp) {
 		if (PageHuge(p)) {