[SCSI] qla4xxx: grab hardware_lock in eh_abort before accessing srb
Mike Christie [Thu, 7 Oct 2010 05:51:17 +0000 (22:51 -0700)]
grab hardware_lock in eh_abort before accessing srb to avoid
race between command completion and get refcount on srb.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Signed-off-by: Ravi Anand <ravi.anand@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

drivers/scsi/qla4xxx/ql4_os.c

index 4b6cdb6..f1c58eb 100644 (file)
@@ -2006,6 +2006,7 @@ static int qla4xxx_eh_abort(struct scsi_cmnd *cmd)
        unsigned int id = cmd->device->id;
        unsigned int lun = cmd->device->lun;
        unsigned long serial = cmd->serial_number;
+       unsigned long flags;
        struct srb *srb = NULL;
        int ret = SUCCESS;
        int wait = 0;
@@ -2014,12 +2015,14 @@ static int qla4xxx_eh_abort(struct scsi_cmnd *cmd)
            "scsi%ld:%d:%d: Abort command issued cmd=%p, pid=%ld\n",
            ha->host_no, id, lun, cmd, serial);
 
+       spin_lock_irqsave(&ha->hardware_lock, flags);
        srb = (struct srb *) CMD_SP(cmd);
-
-       if (!srb)
+       if (!srb) {
+               spin_unlock_irqrestore(&ha->hardware_lock, flags);
                return SUCCESS;
-
+       }
        kref_get(&srb->srb_ref);
+       spin_unlock_irqrestore(&ha->hardware_lock, flags);
 
        if (qla4xxx_abort_task(ha, srb) != QLA_SUCCESS) {
                DEBUG3(printk("scsi%ld:%d:%d: Abort_task mbx failed.\n",