@@ -256,7 +256,6 @@ void dasd_alias_disconnect_device_from_lcu(struct dasd_device *device)
return;
device->discipline->get_uid(device, &uid);
spin_lock_irqsave(&lcu->lock, flags);
- list_del_init(&device->alias_list);
/* make sure that the workers don't use this device */
if (device == lcu->suc_data.device) {
spin_unlock_irqrestore(&lcu->lock, flags);
@@ -283,6 +282,7 @@ void dasd_alias_disconnect_device_from_lcu(struct dasd_device *device)
spin_lock_irqsave(&aliastree.lock, flags);
spin_lock(&lcu->lock);
+ list_del_init(&device->alias_list);
if (list_empty(&lcu->grouplist) &&
list_empty(&lcu->active_devices) &&
list_empty(&lcu->inactive_devices)) {
In dasd_alias_disconnect_device_from_lcu the device is removed from any list on the LCU. Afterwards the LCU is removed from the lcu list if it does not contain devices any longer. The lcu->lock protects the lcu from parallel updates. But to cancel all workers and wait for completion the lcu->lock has to be unlocked. If two devices are removed in parallel and both are removed from the LCU the first device that takes the lcu->lock again will delete the LCU because it is already empty but the second device also tries to free the LCU which leads to a list corruption of the lcu list. Fix by removing the device right before the lcu is checked without unlocking the lcu->lock in between. Fixes: 8e09f21574ea ("[S390] dasd: add hyper PAV support to DASD device driver, part 1") Cc: stable@vger.kernel.org Signed-off-by: Stefan Haberland <sth@linux.ibm.com> Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com> --- drivers/s390/block/dasd_alias.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)