Merge v6.19.9linux-rolling-stable

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 12 insertions, 3 deletions

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index e3bedcbb5f1e..660457e60e2f 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -79,18 +79,27 @@ static void iomap_set_range_uptodate(struct folio *folio, size_t off,
 {
 	struct iomap_folio_state *ifs = folio->private;
 	unsigned long flags;
-	bool uptodate = true;
+	bool mark_uptodate = true;
 
 	if (folio_test_uptodate(folio))
 		return;
 
 	if (ifs) {
 		spin_lock_irqsave(&ifs->state_lock, flags);
-		uptodate = ifs_set_range_uptodate(folio, ifs, off, len);
+		/*
+		 * If a read with bytes pending is in progress, we must not call
+		 * folio_mark_uptodate(). The read completion path
+		 * (iomap_read_end()) will call folio_end_read(), which uses XOR
+		 * semantics to set the uptodate bit. If we set it here, the XOR
+		 * in folio_end_read() will clear it, leaving the folio not
+		 * uptodate.
+		 */
+		mark_uptodate = ifs_set_range_uptodate(folio, ifs, off, len) &&
+				!ifs->read_bytes_pending;
 		spin_unlock_irqrestore(&ifs->state_lock, flags);
 	}
 
-	if (uptodate)
+	if (mark_uptodate)
 		folio_mark_uptodate(folio);
 }