@@ -190,13 +190,6 @@ void scsi_remove_host(struct Scsi_Host *shost)
transport_unregister_device(&shost->shost_gendev);
device_unregister(&shost->shost_dev);
device_del(&shost->shost_gendev);
-
- /*
- * After scsi_remove_host() has returned the scsi LLD module can be
- * unloaded and/or the host resources can be released. Hence wait until
- * the dependent SCSI targets and devices are gone before returning.
- */
- wait_event(shost->targets_wq, atomic_read(&shost->target_count) == 0);
}
EXPORT_SYMBOL(scsi_remove_host);
@@ -406,7 +399,6 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize)
INIT_LIST_HEAD(&shost->starved_list);
init_waitqueue_head(&shost->host_wait);
mutex_init(&shost->scan_mutex);
- init_waitqueue_head(&shost->targets_wq);
index = ida_alloc(&host_index_ida, GFP_KERNEL);
if (index < 0) {
@@ -406,14 +406,9 @@ static void scsi_target_destroy(struct scsi_target *starget)
static void scsi_target_dev_release(struct device *dev)
{
struct device *parent = dev->parent;
- struct Scsi_Host *shost = dev_to_shost(parent);
struct scsi_target *starget = to_scsi_target(dev);
kfree(starget);
-
- if (atomic_dec_return(&shost->target_count) == 0)
- wake_up(&shost->targets_wq);
-
put_device(parent);
}
@@ -528,8 +523,6 @@ static struct scsi_target *scsi_alloc_target(struct device *parent,
starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED;
init_waitqueue_head(&starget->sdev_wq);
- atomic_inc(&shost->target_count);
-
retry:
spin_lock_irqsave(shost->host_lock, flags);
@@ -690,9 +690,6 @@ struct Scsi_Host {
/* ldm bits */
struct device shost_gendev, shost_dev;
- atomic_t target_count;
- wait_queue_head_t targets_wq;
-
/*
* Points to the transport data (if any) which is allocated
* separately
Revert the patch series "Call blk_mq_free_tag_set() earlier" because it introduces a deadlock if the scsi_remove_host() caller holds a reference on a device, target or host. Reported-by: syzbot+bafeb834708b1bb750bc@syzkaller.appspotmail.com Fixes: 16728aaba62e ("scsi: core: Make sure that hosts outlive targets") Signed-off-by: Bart Van Assche <bvanassche@acm.org> --- drivers/scsi/hosts.c | 8 -------- drivers/scsi/scsi_scan.c | 7 ------- include/scsi/scsi_host.h | 3 --- 3 files changed, 18 deletions(-)