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Date:   Sun, 23 Jul 2023 15:35:07 -0700 (PDT)
From:   Hugh Dickins <hughd@google.com>
To:     Andrew Morton <akpm@linux-foundation.org>
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Subject: [PATCH v3 11/13 fix] mm/khugepaged: delete khugepaged_collapse_pte_mapped_thps():
 fix
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Though not yet detected by syzbot, this commit was making the same
mistake with mmap_locked as the previous commit: fix that.

Signed-off-by: Hugh Dickins <hughd@google.com>
---
 mm/khugepaged.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 1c773db26e88..41913730db4c 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -2380,19 +2380,17 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages, int *result,
 				mmap_locked = false;
 				*result = hpage_collapse_scan_file(mm,
 					khugepaged_scan.address, file, pgoff, cc);
+				fput(file);
 				if (*result == SCAN_PTE_MAPPED_HUGEPAGE) {
 					mmap_read_lock(mm);
-					mmap_locked = true;
-					if (hpage_collapse_test_exit(mm)) {
-						fput(file);
+					if (hpage_collapse_test_exit(mm))
 						goto breakouterloop;
-					}
 					*result = collapse_pte_mapped_thp(mm,
 						khugepaged_scan.address, false);
 					if (*result == SCAN_PMD_MAPPED)
 						*result = SCAN_SUCCEED;
+					mmap_read_unlock(mm);
 				}
-				fput(file);
 			} else {
 				*result = hpage_collapse_scan_pmd(mm, vma,
 					khugepaged_scan.address, &mmap_locked, cc);
-- 
2.35.3