diff options
author | Gal Rosen <galr@storwize.com> | 2010-01-21 10:15:32 +0200 |
---|---|---|
committer | James Bottomley <James.Bottomley@suse.de> | 2010-03-08 22:36:53 +0530 |
commit | 0d9dc7c8b9b7fa0f53647423b41056ee1beed735 (patch) | |
tree | 19cab2c6559f6cc5a31abfcf4fc1e33b0528ebc7 | |
parent | d55f88f0275e4b21435957d3d354a79bb9edeec7 (diff) |
[SCSI] scsi_transport_fc: Fix synchronization issue while deleting vport
The issue occur while deleting 60 virtual ports through the sys
interface /sys/class/fc_vports/vport-X/vport_delete. It happen while in
a mistake each request sent twice for the same vport. This interface is
asynchronous, entering the delete request into a work queue, allowing
more than one request to enter to the delete work queue. The result is a
NULL pointer. The first request already delete the vport, while the
second request got a pointer to the vport before the device destroyed.
Re-create vport later cause system freeze.
Solution: Check vport flags before entering the request to the work queue.
[jejb: fixed int<->long problem on spinlock flags variable]
Signed-off-by: Gal Rosen <galr@storwize.com>
Acked-by: James Smart <james.smart@emulex.com>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
-rw-r--r-- | drivers/scsi/scsi_transport_fc.c | 24 |
1 files changed, 12 insertions, 12 deletions
diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/scsi_transport_fc.c index 79660ee3e21..1d5b72173dd 100644 --- a/drivers/scsi/scsi_transport_fc.c +++ b/drivers/scsi/scsi_transport_fc.c @@ -1232,6 +1232,15 @@ store_fc_vport_delete(struct device *dev, struct device_attribute *attr, { struct fc_vport *vport = transport_class_to_vport(dev); struct Scsi_Host *shost = vport_to_shost(vport); + unsigned long flags; + + spin_lock_irqsave(shost->host_lock, flags); + if (vport->flags & (FC_VPORT_DEL | FC_VPORT_CREATING)) { + spin_unlock_irqrestore(shost->host_lock, flags); + return -EBUSY; + } + vport->flags |= FC_VPORT_DELETING; + spin_unlock_irqrestore(shost->host_lock, flags); fc_queue_work(shost, &vport->vport_delete_work); return count; @@ -1821,6 +1830,9 @@ store_fc_host_vport_delete(struct device *dev, struct device_attribute *attr, list_for_each_entry(vport, &fc_host->vports, peers) { if ((vport->channel == 0) && (vport->port_name == wwpn) && (vport->node_name == wwnn)) { + if (vport->flags & (FC_VPORT_DEL | FC_VPORT_CREATING)) + break; + vport->flags |= FC_VPORT_DELETING; match = 1; break; } @@ -3370,18 +3382,6 @@ fc_vport_terminate(struct fc_vport *vport) unsigned long flags; int stat; - spin_lock_irqsave(shost->host_lock, flags); - if (vport->flags & FC_VPORT_CREATING) { - spin_unlock_irqrestore(shost->host_lock, flags); - return -EBUSY; - } - if (vport->flags & (FC_VPORT_DEL)) { - spin_unlock_irqrestore(shost->host_lock, flags); - return -EALREADY; - } - vport->flags |= FC_VPORT_DELETING; - spin_unlock_irqrestore(shost->host_lock, flags); - if (i->f->vport_delete) stat = i->f->vport_delete(vport); else |