[folded-merged] mmthp-recheck-each-page-before-collapsing-file-thp-v4-fix.patch removed from -mm tree

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The patch titled
     Subject: mm/thp: fix deadlock in collapse_file()
has been removed from the -mm tree.  Its filename was
     mmthp-recheck-each-page-before-collapsing-file-thp-v4-fix.patch

This patch was dropped because it was folded into mmthp-recheck-each-page-before-collapsing-file-thp.patch

------------------------------------------------------
From: Song Liu <songliubraving@xxxxxx>
Subject: mm/thp: fix deadlock in collapse_file()

As syzbot reported, we cannot call filemap_flush() with the page locked. 
Remove the filemap_flush() as it is not required.  khugepaged would just
wait until the page is flushed naturally.

Link: http://lkml.kernel.org/r/20191028221414.3685035-1-songliubraving@xxxxxx
Signed-off-by: Song Liu <songliubraving@xxxxxx>
Reported-by: syzbot+efb9e48b9fbdc49bb34a@xxxxxxxxxxxxxxxxxxxxxxxxx
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: William Kucharski <william.kucharski@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 mm/khugepaged.c |   10 +---------
 1 file changed, 1 insertion(+), 9 deletions(-)

--- a/mm/khugepaged.c~mmthp-recheck-each-page-before-collapsing-file-thp-v4-fix
+++ a/mm/khugepaged.c
@@ -1640,16 +1640,8 @@ static void collapse_file(struct mm_stru
 			/*
 			 * khugepaged only works on read-only fd, so this
 			 * page is dirty because it hasn't been flushed
-			 * since first write. There won't be new dirty
-			 * pages.
-			 *
-			 * Trigger async flush here and hope the writeback
-			 * is done when khugepaged revisits this page.
-			 *
-			 * This is a one-off situation. We are not forcing
-			 * writeback in loop.
+			 * since first write.
 			 */
-			filemap_flush(mapping);
 			result = SCAN_FAIL;
 			goto out_unlock;
 		}
_

Patches currently in -mm which might be from songliubraving@xxxxxx are

mmthp-recheck-each-page-before-collapsing-file-thp.patch




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