md/raid1: Don't release reference to device while handling read error.
When we get a read error, we arrange for raid1d to handle it.
Currently we release the reference on the device. This can result
in
conf->mirrors[read_disk].rdev
being NULL in fix_read_error, if the device happens to get removed
before the read error is handled.
So instead keep the reference until the read error has been fully
handled.
Reported-by: hank <pyu@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 55ccf47..e913356 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -333,9 +333,10 @@
spin_unlock_irqrestore(&conf->device_lock, flags);
}
- if (uptodate)
+ if (uptodate) {
raid_end_bio_io(r1_bio);
- else {
+ rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev);
+ } else {
/*
* oops, read error:
*/
@@ -349,9 +350,8 @@
(unsigned long long)r1_bio->sector);
set_bit(R1BIO_ReadError, &r1_bio->state);
reschedule_retry(r1_bio);
+ /* don't drop the reference on read_disk yet */
}
-
- rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev);
}
static void close_write(struct r1bio *r1_bio)
@@ -2229,6 +2229,7 @@
unfreeze_array(conf);
} else
md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev);
+ rdev_dec_pending(conf->mirrors[r1_bio->read_disk].rdev, conf->mddev);
bio = r1_bio->bios[r1_bio->read_disk];
bdevname(bio->bi_bdev, b);