Re: [PATCH v4 1/2] scsi: Add intermediate STARGET_REMOVE state to scsi_target_state

From: Xiong Zhou
Date: Tue Apr 12 2016 - 09:02:00 EST


How about this?

drivers/scsi/scsi_scan: mark STARGET_REMOVE state before destroy

Signed-off-by: Xiong Zhou <jencce.kernel@xxxxxxxxx>
---
drivers/scsi/scsi_scan.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 27df7e7..21092e5 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -395,6 +395,8 @@ static void scsi_target_reap_ref_release(struct kref *kref)
transport_remove_device(&starget->dev);
device_del(&starget->dev);
}
+
+ starget->state = STARGET_REMOVE;
scsi_target_destroy(starget);
}

@@ -465,6 +467,7 @@ static struct scsi_target
*scsi_alloc_target(struct device *parent,
dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error);
/* don't want scsi_target_reap to do the final
* put because it will be under the host lock */
+ starget->state = STARGET_REMOVE;
scsi_target_destroy(starget);
return NULL;
}
--
1.8.3.1

On Tue, Apr 5, 2016 at 5:50 PM, Johannes Thumshirn <jthumshirn@xxxxxxx> wrote:
> 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
> bc3f02a795d3b4faa99d37390174be2a75d091bd and
> 40998193560dab6c3ce8d25f4fa58a23e252ef38 in a more comprehensive way.
>
> Signed-off-by: Johannes Thumshirn <jthumshirn@xxxxxxx>
> Fixes: 40998193560dab6c3ce8d25f4fa58a23e252ef38
> Cc: stable@xxxxxxxxxxxxxxx
> Reviewed-by: Ewan D. Milne <emilne@xxxxxxxxxx>
> Reviewed-by: Hannes Reinecke <hare@xxxxxxxx>
> Reviewed-by: James Bottomley <jejb@xxxxxxxxxxxxxxxxxx>
> ---
> drivers/scsi/scsi_scan.c | 2 ++
> drivers/scsi/scsi_sysfs.c | 2 ++
> include/scsi/scsi_device.h | 1 +
> 3 files changed, 5 insertions(+)
>
> diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
> index 6a82066..63b8bca 100644
> --- a/drivers/scsi/scsi_scan.c
> +++ b/drivers/scsi/scsi_scan.c
> @@ -315,6 +315,8 @@ 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_REMOVE &&
> + starget->state != STARGET_CREATED);
> starget->state = STARGET_DEL;
> transport_destroy_device(dev);
> spin_lock_irqsave(shost->host_lock, flags);
> diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
> index 00bc721..0df82e8 100644
> --- a/drivers/scsi/scsi_sysfs.c
> +++ b/drivers/scsi/scsi_sysfs.c
> @@ -1279,11 +1279,13 @@ 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);
> diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
> index f63a167..2bffaa6 100644
> --- a/include/scsi/scsi_device.h
> +++ b/include/scsi/scsi_device.h
> @@ -240,6 +240,7 @@ scmd_printk(const char *, const struct scsi_cmnd *, const char *, ...);
> enum scsi_target_state {
> STARGET_CREATED = 1,
> STARGET_RUNNING,
> + STARGET_REMOVE,
> STARGET_DEL,
> };
>
> --
> 1.8.5.6
>