[PATCH 4.14 127/246] md/raid1: add error handling of read error from FailFast device

From: Greg Kroah-Hartman
Date: Wed Aug 01 2018 - 13:18:11 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Gioh Kim <gi-oh.kim@xxxxxxxxxxxxxxxx>

[ Upstream commit b33d10624fdc15cdf1495f3f00481afccec76783 ]

Current handle_read_error() function calls fix_read_error()
only if md device is RW and rdev does not include FailFast flag.
It does not handle a read error from a RW device including
FailFast flag.

I am not sure it is intended. But I found that write IO error
sets rdev faulty. The md module should handle the read IO error and
write IO error equally. So I think read IO error should set rdev faulty.

Signed-off-by: Gioh Kim <gi-oh.kim@xxxxxxxxxxxxxxxx>
Reviewed-by: Jack Wang <jinpu.wang@xxxxxxxxxxxxxxxx>
Signed-off-by: Shaohua Li <shli@xxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/md/raid1.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -2462,6 +2462,8 @@ static void handle_read_error(struct r1c
fix_read_error(conf, r1_bio->read_disk,
r1_bio->sector, r1_bio->sectors);
unfreeze_array(conf);
+ } else if (mddev->ro == 0 && test_bit(FailFast, &rdev->flags)) {
+ md_error(mddev, rdev);
} else {
r1_bio->bios[r1_bio->read_disk] = IO_BLOCKED;
}