struct list_head    siblings;   /* list of all devices on this host */
        struct list_head    same_target_siblings; /* just the devices sharing same target id */
 
-       volatile unsigned short device_busy;    /* commands actually active on low-level */
+       unsigned int device_busy;       /* commands actually active on
+                                        * low-level. protected by queue_lock. */
        spinlock_t sdev_lock;           /* also the request queue_lock */
        spinlock_t list_lock;
        struct list_head cmd_list;      /* queue of in use SCSI Command structures */
 
        wait_queue_head_t       host_wait;
        struct scsi_host_template *hostt;
        struct scsi_transport_template *transportt;
-       volatile unsigned short host_busy;   /* commands actually active on low-level */
-       volatile unsigned short host_failed; /* commands that failed. */
+
+       /*
+        * The following two fields are protected with host_lock;
+        * however, eh routines can safely access during eh processing
+        * without acquiring the lock.
+        */
+       unsigned int host_busy;            /* commands actually active on low-level */
+       unsigned int host_failed;          /* commands that failed. */
     
        unsigned short host_no;  /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
        int resetting; /* if set, it means that last_reset is a valid value */