From: Andrew Morton <akpm@linux-foundation.org>
Date: Sat, 10 Dec 2022 03:31:11 +0000 (-0800)
Subject: Merge branch 'mm-hotfixes-stable' into mm-stable
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=3b91010500eba3601e906b0e92cf84fab4d895d1;p=linux.git

Merge branch 'mm-hotfixes-stable' into mm-stable
---

3b91010500eba3601e906b0e92cf84fab4d895d1
diff --cc mm/shmem.c
index f418d21205be1,82911fefc2d5e..17adb7f6f6e43
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@@ -948,8 -945,18 +948,17 @@@ static void shmem_undo_range(struct ino
  		folio_batch_remove_exceptionals(&fbatch);
  		folio_batch_release(&fbatch);
  		cond_resched();
 -		index++;
  	}
  
+ 	/*
+ 	 * When undoing a failed fallocate, we want none of the partial folio
+ 	 * zeroing and splitting below, but shall want to truncate the whole
+ 	 * folio when !uptodate indicates that it was added by this fallocate,
+ 	 * even when [lstart, lend] covers only a part of the folio.
+ 	 */
+ 	if (unfalloc)
+ 		goto whole_folios;
+ 
  	same_folio = (lstart >> PAGE_SHIFT) == (lend >> PAGE_SHIFT);
  	folio = shmem_get_partial_folio(inode, lstart >> PAGE_SHIFT);
  	if (folio) {