This is a note to let you know that I've just added the patch titled
md/raid10: use dereference_rdev_and_rrdev() to get devices
to the 6.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
md-raid10-use-dereference_rdev_and_rrdev-to-get-devi.patch
and it can be found in the queue-6.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 641825b4700ba896c5f5704e67e05cd3451e4e78
Author: Li Nan <linan122@xxxxxxxxxx>
Date: Sat Jul 1 16:05:29 2023 +0800
md/raid10: use dereference_rdev_and_rrdev() to get devices
[ Upstream commit 673643490b9a0eb3b25633abe604f62b8f63dba1 ]
Commit 2ae6aaf76912 ("md/raid10: fix io loss while replacement replace
rdev") reads replacement first to prevent io loss. However, there are same
issue in wait_blocked_dev() and raid10_handle_discard(), too. Fix it by
using dereference_rdev_and_rrdev() to get devices.
Fixes: d30588b2731f ("md/raid10: improve raid10 discard request")
Fixes: f2e7e269a752 ("md/raid10: pull the code that wait for blocked dev into one function")
Signed-off-by: Li Nan <linan122@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230701080529.2684932-4-linan666@xxxxxxxxxxxxxxx
Signed-off-by: Song Liu <song@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index f47fd50651c45..925ab30c15d49 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1350,11 +1350,9 @@ static void wait_blocked_dev(struct mddev *mddev, struct r10bio *r10_bio)
blocked_rdev = NULL;
rcu_read_lock();
for (i = 0; i < conf->copies; i++) {
- struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev);
- struct md_rdev *rrdev = rcu_dereference(
- conf->mirrors[i].replacement);
- if (rdev == rrdev)
- rrdev = NULL;
+ struct md_rdev *rdev, *rrdev;
+
+ rdev = dereference_rdev_and_rrdev(&conf->mirrors[i], &rrdev);
if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
atomic_inc(&rdev->nr_pending);
blocked_rdev = rdev;
@@ -1790,10 +1788,9 @@ static int raid10_handle_discard(struct mddev *mddev, struct bio *bio)
*/
rcu_read_lock();
for (disk = 0; disk < geo->raid_disks; disk++) {
- struct md_rdev *rdev = rcu_dereference(conf->mirrors[disk].rdev);
- struct md_rdev *rrdev = rcu_dereference(
- conf->mirrors[disk].replacement);
+ struct md_rdev *rdev, *rrdev;
+ rdev = dereference_rdev_and_rrdev(&conf->mirrors[disk], &rrdev);
r10_bio->devs[disk].bio = NULL;
r10_bio->devs[disk].repl_bio = NULL;
