This is a note to let you know that I've just added the patch titled
dm-raid: add a new helper prepare_suspend() in md_personality
to the 6.7-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:
dm-raid-add-a-new-helper-prepare_suspend-in-md_perso.patch
and it can be found in the queue-6.7 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 2eea0920d6a4eec9ef6bf65a03cc3a32bb1fb44e
Author: Yu Kuai <yukuai3@xxxxxxxxxx>
Date: Tue Mar 5 15:23:04 2024 +0800
dm-raid: add a new helper prepare_suspend() in md_personality
[ Upstream commit 5625ff8b72b0e5c13b0fc1fc1f198155af45f729 ]
There are no functional changes for now, prepare to fix a deadlock for
dm-raid456.
Cc: stable@xxxxxxxxxxxxxxx # v6.7+
Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
Signed-off-by: Xiao Ni <xni@xxxxxxxxxx>
Acked-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Song Liu <song@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240305072306.2562024-8-yukuai1@xxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 8d38cdb221453..b8f5304ca00d1 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -3803,6 +3803,23 @@ static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
blk_limits_io_opt(limits, chunk_size_bytes * mddev_data_stripes(rs));
}
+static void raid_presuspend(struct dm_target *ti)
+{
+ struct raid_set *rs = ti->private;
+ struct mddev *mddev = &rs->md;
+
+ if (!reshape_interrupted(mddev))
+ return;
+
+ /*
+ * For raid456, if reshape is interrupted, IO across reshape position
+ * will never make progress, while caller will wait for IO to be done.
+ * Inform raid456 to handle those IO to prevent deadlock.
+ */
+ if (mddev->pers && mddev->pers->prepare_suspend)
+ mddev->pers->prepare_suspend(mddev);
+}
+
static void raid_postsuspend(struct dm_target *ti)
{
struct raid_set *rs = ti->private;
@@ -4087,6 +4104,7 @@ static struct target_type raid_target = {
.message = raid_message,
.iterate_devices = raid_iterate_devices,
.io_hints = raid_io_hints,
+ .presuspend = raid_presuspend,
.postsuspend = raid_postsuspend,
.preresume = raid_preresume,
.resume = raid_resume,
diff --git a/drivers/md/md.h b/drivers/md/md.h
index ea0fd76c17e75..24261f9b676d5 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -649,6 +649,7 @@ struct md_personality
int (*start_reshape) (struct mddev *mddev);
void (*finish_reshape) (struct mddev *mddev);
void (*update_reshape_pos) (struct mddev *mddev);
+ void (*prepare_suspend) (struct mddev *mddev);
/* quiesce suspends or resumes internal processing.
* 1 - stop new actions and wait for action io to complete
* 0 - return to normal behaviour
