diff options
| author | Bart Van Assche <bvanassche@acm.org> | 2022-08-21 15:05:02 -0700 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2022-09-01 01:02:10 -0400 |
| commit | f782201ebc2b5f6c7a22e586e8eb81fe1d9e4801 (patch) | |
| tree | f76d4ca8cdc0bf5816cb135df358164b0e909519 | |
| parent | d94b2d00f7bfa0c555e7b8724b1faa037d57d150 (diff) | |
scsi: core: Revert "Make sure that targets outlive devices"
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.
Link: https://lore.kernel.org/r/20220821220502.13685-5-bvanassche@acm.org
Fixes: fe442604199e ("scsi: core: Make sure that targets outlive devices")
Reported-by: syzbot+bafeb834708b1bb750bc@syzkaller.appspotmail.com
Tested-by: Kenneth R. Crudup <kenny@panix.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
| -rw-r--r-- | drivers/scsi/scsi_scan.c | 2 | ||||
| -rw-r--r-- | drivers/scsi/scsi_sysfs.c | 20 | ||||
| -rw-r--r-- | include/scsi/scsi_device.h | 2 |
3 files changed, 3 insertions, 21 deletions
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 4c1efd6a3b0c..91ac901a6682 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -521,8 +521,6 @@ static struct scsi_target *scsi_alloc_target(struct device *parent, starget->state = STARGET_CREATED; starget->scsi_level = SCSI_2; starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED; - init_waitqueue_head(&starget->sdev_wq); - retry: spin_lock_irqsave(shost->host_lock, flags); diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c index 282b32781e8c..aa70d9282161 100644 --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -443,9 +443,7 @@ static void scsi_device_cls_release(struct device *class_dev) static void scsi_device_dev_release_usercontext(struct work_struct *work) { - struct scsi_device *sdev = container_of(work, struct scsi_device, - ew.work); - struct scsi_target *starget = sdev->sdev_target; + struct scsi_device *sdev; struct device *parent; struct list_head *this, *tmp; struct scsi_vpd *vpd_pg80 = NULL, *vpd_pg83 = NULL; @@ -454,6 +452,8 @@ static void scsi_device_dev_release_usercontext(struct work_struct *work) unsigned long flags; struct module *mod; + sdev = container_of(work, struct scsi_device, ew.work); + mod = sdev->host->hostt->module; scsi_dh_release_device(sdev); @@ -516,9 +516,6 @@ static void scsi_device_dev_release_usercontext(struct work_struct *work) kfree(sdev->inquiry); kfree(sdev); - if (starget && atomic_dec_return(&starget->sdev_count) == 0) - wake_up(&starget->sdev_wq); - if (parent) put_device(parent); module_put(mod); @@ -1538,14 +1535,6 @@ static void __scsi_remove_target(struct scsi_target *starget) goto restart; } spin_unlock_irqrestore(shost->host_lock, flags); - - /* - * After scsi_remove_target() returns its caller can remove resources - * associated with @starget, e.g. an rport or session. Wait until all - * devices associated with @starget have been removed to prevent that - * a SCSI error handling callback function triggers a use-after-free. - */ - wait_event(starget->sdev_wq, atomic_read(&starget->sdev_count) == 0); } /** @@ -1656,9 +1645,6 @@ void scsi_sysfs_device_initialize(struct scsi_device *sdev) list_add_tail(&sdev->same_target_siblings, &starget->devices); list_add_tail(&sdev->siblings, &shost->__devices); spin_unlock_irqrestore(shost->host_lock, flags); - - atomic_inc(&starget->sdev_count); - /* * device can now only be removed via __scsi_remove_device() so hold * the target. Target will be held in CREATED state until something diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index 3113471ca375..2493bd65351a 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -309,8 +309,6 @@ struct scsi_target { struct list_head devices; struct device dev; struct kref reap_ref; /* last put renders target invisible */ - atomic_t sdev_count; - wait_queue_head_t sdev_wq; unsigned int channel; unsigned int id; /* target id ... replace * scsi_device.id eventually */ |