6.15-stable review patch. If anyone has any objections, please let me know.
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From: Zheng Qixing zhengqixing@huawei.com
[ Upstream commit c0ffeb648000acdc932da7a9d33fd65e9263c54c ]
During RAID resync, faulty rdev cannot be removed and will result in "Device or resource busy" error when attempting hot removal.
Reproduction steps: mdadm -Cv /dev/md0 -l1 -n3 -e1.2 /dev/sd{b..d} mdadm /dev/md0 -f /dev/sdb mdadm /dev/md0 -r /dev/sdb -> mdadm: hot remove failed for /dev/sdb: Device or resource busy
After commit 4b10a3bc67c1 ("md: ensure resync is prioritized over recovery"), when a device becomes faulty during resync, the md_choose_sync_action() function returns early without calling remove_and_add_spares(), preventing faulty device removal.
This patch extracts a helper function remove_spares() to support removing faulty devices during RAID resync operations.
Fixes: 4b10a3bc67c1 ("md: ensure resync is prioritized over recovery") Signed-off-by: Zheng Qixing zhengqixing@huawei.com Reviewed-by: Li Nan linan122@huawei.com Link: https://lore.kernel.org/linux-raid/20250707075412.150301-1-zhengqixing@huawe... Signed-off-by: Yu Kuai yukuai3@huawei.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/md.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c index 9daa78c5fe33..0de87d451a47 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -9380,17 +9380,11 @@ static bool md_spares_need_change(struct mddev *mddev) return false; }
-static int remove_and_add_spares(struct mddev *mddev, - struct md_rdev *this) +static int remove_spares(struct mddev *mddev, struct md_rdev *this) { struct md_rdev *rdev; - int spares = 0; int removed = 0;
- if (this && test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) - /* Mustn't remove devices when resync thread is running */ - return 0; - rdev_for_each(rdev, mddev) { if ((this == NULL || rdev == this) && rdev_removeable(rdev) && !mddev->pers->hot_remove_disk(mddev, rdev)) { @@ -9404,6 +9398,21 @@ static int remove_and_add_spares(struct mddev *mddev, if (removed && mddev->kobj.sd) sysfs_notify_dirent_safe(mddev->sysfs_degraded);
+ return removed; +} + +static int remove_and_add_spares(struct mddev *mddev, + struct md_rdev *this) +{ + struct md_rdev *rdev; + int spares = 0; + int removed = 0; + + if (this && test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) + /* Mustn't remove devices when resync thread is running */ + return 0; + + removed = remove_spares(mddev, this); if (this && removed) goto no_add;
@@ -9446,6 +9455,7 @@ static bool md_choose_sync_action(struct mddev *mddev, int *spares)
/* Check if resync is in progress. */ if (mddev->recovery_cp < MaxSector) { + remove_spares(mddev, NULL); set_bit(MD_RECOVERY_SYNC, &mddev->recovery); clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery); return true;