md/r5cache: fix set_syndrome_sources() for data in cache

Before this patch, device InJournal will be included in prexor
(SYNDROME_SRC_WANT_DRAIN) but not in reconstruct (SYNDROME_SRC_WRITTEN). So it
will break parity calculation. With srctype == SYNDROME_SRC_WRITTEN, we need
include both dev with non-null ->written and dev with R5_InJournal. This fixes
logic in 1e6d690(md/r5cache: caching phase of r5cache)

Cc: stable@vger.kernel.org (v4.10+)
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 6bfedfc..ed5cd70 100644 (file)
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -1401,7 +1401,8 @@ static int set_syndrome_sources(struct page **srcs,
                     (test_bit(R5_Wantdrain, &dev->flags) ||
                      test_bit(R5_InJournal, &dev->flags))) ||
                    (srctype == SYNDROME_SRC_WRITTEN &&
-                    dev->written)) {
+                    (dev->written ||
+                     test_bit(R5_InJournal, &dev->flags)))) {
                        if (test_bit(R5_InJournal, &dev->flags))
                                srcs[slot] = sh->dev[i].orig_page;
                        else