md: allow removing faulty rdev during resync

[ Upstream commit c0ffeb6480 ]

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 4b10a3bc67 ("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: 4b10a3bc67 ("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@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Zheng Qixing 2025-07-07 15:54:12 +08:00 committed by Greg Kroah-Hartman
parent 8911416af0
commit 1d8b515d2d

View File

@ -9456,17 +9456,11 @@ 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)) {
@ -9480,6 +9474,21 @@ 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;
@ -9522,6 +9531,7 @@ 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;