From: Song Liu <songliubraving@fb.com>
Date: Mon, 13 Mar 2017 20:44:35 +0000 (-0700)
Subject: md/r5cache: fix set_syndrome_sources() for data in cache
X-Git-Tag: v4.10.6~19
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3e037a0fe0b67412eb743c66d22394dca18e6d54;p=thirdparty%2Fkernel%2Fstable.git

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

commit 0977762f6d15f13caccc20d71a5dec47d098907d upstream.

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)

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 3c7e106c12a24..6661db2c85f00 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -1364,7 +1364,8 @@ 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