This is a note to let you know that I've just added the patch titled
md: fix data corruption for raid456 when reshape restart while grow up
to the 4.19-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-fix-data-corruption-for-raid456-when-reshape-rest.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 8c977d8f9a4252e9b335230eb09b5cc3f52e6db1
Author: Yu Kuai <yukuai3@xxxxxxxxxx>
Date: Fri May 12 09:56:07 2023 +0800
md: fix data corruption for raid456 when reshape restart while grow up
[ Upstream commit 873f50ece41aad5c4f788a340960c53774b5526e ]
Currently, if reshape is interrupted, echo "reshape" to sync_action will
restart reshape from scratch, for example:
echo frozen > sync_action
echo reshape > sync_action
This will corrupt data before reshape_position if the array is growing,
fix the problem by continue reshape from reshape_position.
Reported-by: Peter Neuwirth <reddunur@xxxxxxxxx>
Link: https://lore.kernel.org/linux-raid/e2f96772-bfbc-f43b-6da1-f520e5164536@xxxxxxxxx/
Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
Signed-off-by: Song Liu <song@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230512015610.821290-3-yukuai1@xxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 2e23a898fc978..6b074c2202d5a 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -4639,11 +4639,21 @@ action_store(struct mddev *mddev, const char *page, size_t len)
return -EINVAL;
err = mddev_lock(mddev);
if (!err) {
- if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
+ if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {
err = -EBUSY;
- else {
+ } else if (mddev->reshape_position == MaxSector ||
+ mddev->pers->check_reshape == NULL ||
+ mddev->pers->check_reshape(mddev)) {
clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
err = mddev->pers->start_reshape(mddev);
+ } else {
+ /*
+ * If reshape is still in progress, and
+ * md_check_recovery() can continue to reshape,
+ * don't restart reshape because data can be
+ * corrupted for raid456.
+ */
+ clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
}
mddev_unlock(mddev);
}
