From 4aaf7694f841edc96fe0f72958aabe59204b3611 Mon Sep 17 00:00:00 2001
From: Guoqing Jiang <gqjiang@suse.com>
Date: Tue, 4 Jul 2017 11:20:30 +0800
Subject: [PATCH] md/bitmap: don't read page from device with Bitmap_sync
Git-commit: 4aaf7694f841edc96fe0f72958aabe59204b3611
Patch-mainline: v4.13-rc2
References: fate#322738,fate#322919,fate#322950,fate#323773
The device owns Bitmap_sync flag needs recovery
to become in sync, and read page from this type
device could get stale status.
Also add comments for Bitmap_sync bit per the
suggestion from Shaohua and Neil.
Previous disscussion can be found here:
https://marc.info/?t=149760428900004&r=1&w=2
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Coly Li <colyli@suse.de>
---
drivers/md/bitmap.c | 3 ++-
drivers/md/md.h | 4 +++-
2 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index f4eace5ea184..40f3cd7eab0f 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -156,7 +156,8 @@ static int read_sb_page(struct mddev *mddev, loff_t offset,
rdev_for_each(rdev, mddev) {
if (! test_bit(In_sync, &rdev->flags)
- || test_bit(Faulty, &rdev->flags))
+ || test_bit(Faulty, &rdev->flags)
+ || test_bit(Bitmap_sync, &rdev->flags))
continue;
target = offset + index * (PAGE_SIZE/512);
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 991f0fe2dcc6..b50eb4ac1b82 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -134,7 +134,9 @@ enum flag_bits {
Faulty, /* device is known to have a fault */
In_sync, /* device is in_sync with rest of array */
Bitmap_sync, /* ..actually, not quite In_sync. Need a
- * bitmap-based recovery to get fully in sync
+ * bitmap-based recovery to get fully in sync.
+ * The bit is only meaningful before device
+ * has been passed to pers->hot_add_disk.
*/
WriteMostly, /* Avoid reading if at all possible */
AutoDetected, /* added by auto-detect */
--
2.13.1