scsi: Add intermediate STARGET_REMOVE state to scsi_target_state

Add intermediate STARGET_REMOVE state to scsi_target_state to avoid
running into the BUG_ON() in scsi_target_reap(). The STARGET_REMOVE
state is only valid in the path from scsi_remove_target() to
scsi_target_destroy() indicating this target is going to be removed.

This re-fixes the problem introduced in commits bc3f02a795 ("[SCSI]
scsi_remove_target: fix softlockup regression on hot remove") and
4099819356 ("scsi: restart list search after unlock in
scsi_remove_target") in a more comprehensive way.

[mkp: Included James' fix for scsi_target_destroy()]

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Fixes: 4099819356
Cc: stable@vger.kernel.org
Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: James Bottomley <jejb@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Johannes Thumshirn 2016-04-05 11:50:44 +02:00 коммит произвёл Martin K. Petersen
Родитель be2a266d2a
Коммит f05795d3d7
3 изменённых файлов: 4 добавлений и 0 удалений

Просмотреть файл

@ -319,6 +319,7 @@ static void scsi_target_destroy(struct scsi_target *starget)
struct Scsi_Host *shost = dev_to_shost(dev->parent);
unsigned long flags;
BUG_ON(starget->state == STARGET_DEL);
starget->state = STARGET_DEL;
transport_destroy_device(dev);
spin_lock_irqsave(shost->host_lock, flags);

Просмотреть файл

@ -1374,11 +1374,13 @@ restart:
spin_lock_irqsave(shost->host_lock, flags);
list_for_each_entry(starget, &shost->__targets, siblings) {
if (starget->state == STARGET_DEL ||
starget->state == STARGET_REMOVE ||
starget == last_target)
continue;
if (starget->dev.parent == dev || &starget->dev == dev) {
kref_get(&starget->reap_ref);
last_target = starget;
starget->state = STARGET_REMOVE;
spin_unlock_irqrestore(shost->host_lock, flags);
__scsi_remove_target(starget);
scsi_target_reap(starget);

Просмотреть файл

@ -248,6 +248,7 @@ scmd_printk(const char *, const struct scsi_cmnd *, const char *, ...);
enum scsi_target_state {
STARGET_CREATED = 1,
STARGET_RUNNING,
STARGET_REMOVE,
STARGET_DEL,
};