Merge ../linux-2.6-watchdog-mm
[pandora-kernel.git] / drivers / char / ipmi / ipmi_msghandler.c
index 34a4fd1..53582b5 100644 (file)
 
 #define PFX "IPMI message handler: "
 
-#define IPMI_DRIVER_VERSION "39.0"
+#define IPMI_DRIVER_VERSION "39.1"
 
 static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void);
 static int ipmi_init_msghandler(void);
 
-static int initialized = 0;
+static int initialized;
 
 #ifdef CONFIG_PROC_FS
-static struct proc_dir_entry *proc_ipmi_root = NULL;
+static struct proc_dir_entry *proc_ipmi_root;
 #endif /* CONFIG_PROC_FS */
 
+/* Remain in auto-maintenance mode for this amount of time (in ms). */
+#define IPMI_MAINTENANCE_MODE_TIMEOUT 30000
+
 #define MAX_EVENTS_IN_QUEUE    25
 
 /* Don't let a message sit in a queue forever, always time it with at lest
@@ -193,17 +196,28 @@ struct ipmi_smi
 
        struct kref refcount;
 
+       /* Used for a list of interfaces. */
+       struct list_head link;
+
        /* The list of upper layers that are using me.  seq_lock
         * protects this. */
        struct list_head users;
 
+       /* Information to supply to users. */
+       unsigned char ipmi_version_major;
+       unsigned char ipmi_version_minor;
+
        /* Used for wake ups at startup. */
        wait_queue_head_t waitq;
 
        struct bmc_device *bmc;
        char *my_dev_name;
+       char *sysfs_name;
 
-       /* This is the lower-layer's sender routine. */
+       /* This is the lower-layer's sender routine.  Note that you
+        * must either be holding the ipmi_interfaces_mutex or be in
+        * an umpreemptible region to use this.  You must fetch the
+        * value into a local variable and make sure it is not NULL. */
        struct ipmi_smi_handlers *handlers;
        void                     *send_info;
 
@@ -242,6 +256,7 @@ struct ipmi_smi
        spinlock_t       events_lock; /* For dealing with event stuff. */
        struct list_head waiting_events;
        unsigned int     waiting_events_count; /* How many events in queue? */
+       int              delivering_events;
 
        /* The event receiver for my BMC, only really used at panic
           shutdown as a place to store this. */
@@ -250,6 +265,12 @@ struct ipmi_smi
        unsigned char local_sel_device;
        unsigned char local_event_generator;
 
+       /* For handling of maintenance mode. */
+       int maintenance_mode;
+       int maintenance_mode_enable;
+       int auto_maintenance_timeout;
+       spinlock_t maintenance_mode_lock; /* Used in a timer... */
+
        /* A cheap hack, if this is non-null and a message to an
           interface comes in with a NULL user, call this routine with
           it.  Note that the message will still be freed by the
@@ -338,13 +359,6 @@ struct ipmi_smi
 };
 #define to_si_intf_from_dev(device) container_of(device, struct ipmi_smi, dev)
 
-/* Used to mark an interface entry that cannot be used but is not a
- * free entry, either, primarily used at creation and deletion time so
- * a slot doesn't get reused too quickly. */
-#define IPMI_INVALID_INTERFACE_ENTRY ((ipmi_smi_t) ((long) 1))
-#define IPMI_INVALID_INTERFACE(i) (((i) == NULL) \
-                                  || (i == IPMI_INVALID_INTERFACE_ENTRY))
-
 /**
  * The driver model view of the IPMI messaging driver.
  */
@@ -354,16 +368,13 @@ static struct device_driver ipmidriver = {
 };
 static DEFINE_MUTEX(ipmidriver_mutex);
 
-#define MAX_IPMI_INTERFACES 4
-static ipmi_smi_t ipmi_interfaces[MAX_IPMI_INTERFACES];
-
-/* Directly protects the ipmi_interfaces data structure. */
-static DEFINE_SPINLOCK(interfaces_lock);
+static struct list_head ipmi_interfaces = LIST_HEAD_INIT(ipmi_interfaces);
+static DEFINE_MUTEX(ipmi_interfaces_mutex);
 
 /* List of watchers that want to know when smi's are added and
    deleted. */
 static struct list_head smi_watchers = LIST_HEAD_INIT(smi_watchers);
-static DECLARE_RWSEM(smi_watchers_sem);
+static DEFINE_MUTEX(smi_watchers_mutex);
 
 
 static void free_recv_msg_list(struct list_head *q)
@@ -376,13 +387,23 @@ static void free_recv_msg_list(struct list_head *q)
        }
 }
 
+static void free_smi_msg_list(struct list_head *q)
+{
+       struct ipmi_smi_msg *msg, *msg2;
+
+       list_for_each_entry_safe(msg, msg2, q, link) {
+               list_del(&msg->link);
+               ipmi_free_smi_msg(msg);
+       }
+}
+
 static void clean_up_interface_data(ipmi_smi_t intf)
 {
        int              i;
        struct cmd_rcvr  *rcvr, *rcvr2;
        struct list_head list;
 
-       free_recv_msg_list(&intf->waiting_msgs);
+       free_smi_msg_list(&intf->waiting_msgs);
        free_recv_msg_list(&intf->waiting_events);
 
        /* Wholesale remove all the entries from the list in the
@@ -413,48 +434,84 @@ static void intf_free(struct kref *ref)
        kfree(intf);
 }
 
+struct watcher_entry {
+       int              intf_num;
+       ipmi_smi_t       intf;
+       struct list_head link;
+};
+
 int ipmi_smi_watcher_register(struct ipmi_smi_watcher *watcher)
 {
-       int           i;
-       unsigned long flags;
+       ipmi_smi_t intf;
+       struct list_head to_deliver = LIST_HEAD_INIT(to_deliver);
+       struct watcher_entry *e, *e2;
+
+       mutex_lock(&smi_watchers_mutex);
+
+       mutex_lock(&ipmi_interfaces_mutex);
 
-       down_write(&smi_watchers_sem);
-       list_add(&(watcher->link), &smi_watchers);
-       up_write(&smi_watchers_sem);
-       spin_lock_irqsave(&interfaces_lock, flags);
-       for (i = 0; i < MAX_IPMI_INTERFACES; i++) {
-               ipmi_smi_t intf = ipmi_interfaces[i];
-               if (IPMI_INVALID_INTERFACE(intf))
+       /* Build a list of things to deliver. */
+       list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
+               if (intf->intf_num == -1)
                        continue;
-               spin_unlock_irqrestore(&interfaces_lock, flags);
-               watcher->new_smi(i, intf->si_dev);
-               spin_lock_irqsave(&interfaces_lock, flags);
+               e = kmalloc(sizeof(*e), GFP_KERNEL);
+               if (!e)
+                       goto out_err;
+               kref_get(&intf->refcount);
+               e->intf = intf;
+               e->intf_num = intf->intf_num;
+               list_add_tail(&e->link, &to_deliver);
+       }
+
+       /* We will succeed, so add it to the list. */
+       list_add(&watcher->link, &smi_watchers);
+
+       mutex_unlock(&ipmi_interfaces_mutex);
+
+       list_for_each_entry_safe(e, e2, &to_deliver, link) {
+               list_del(&e->link);
+               watcher->new_smi(e->intf_num, e->intf->si_dev);
+               kref_put(&e->intf->refcount, intf_free);
+               kfree(e);
        }
-       spin_unlock_irqrestore(&interfaces_lock, flags);
+
+       mutex_unlock(&smi_watchers_mutex);
+
        return 0;
+
+ out_err:
+       mutex_unlock(&ipmi_interfaces_mutex);
+       mutex_unlock(&smi_watchers_mutex);
+       list_for_each_entry_safe(e, e2, &to_deliver, link) {
+               list_del(&e->link);
+               kref_put(&e->intf->refcount, intf_free);
+               kfree(e);
+       }
+       return -ENOMEM;
 }
 
 int ipmi_smi_watcher_unregister(struct ipmi_smi_watcher *watcher)
 {
-       down_write(&smi_watchers_sem);
+       mutex_lock(&smi_watchers_mutex);
        list_del(&(watcher->link));
-       up_write(&smi_watchers_sem);
+       mutex_unlock(&smi_watchers_mutex);
        return 0;
 }
 
+/*
+ * Must be called with smi_watchers_mutex held.
+ */
 static void
 call_smi_watchers(int i, struct device *dev)
 {
        struct ipmi_smi_watcher *w;
 
-       down_read(&smi_watchers_sem);
        list_for_each_entry(w, &smi_watchers, link) {
                if (try_module_get(w->owner)) {
                        w->new_smi(i, dev);
                        module_put(w->owner);
                }
        }
-       up_read(&smi_watchers_sem);
 }
 
 static int
@@ -580,6 +637,17 @@ static void deliver_response(struct ipmi_recv_msg *msg)
        }
 }
 
+static void
+deliver_err_response(struct ipmi_recv_msg *msg, int err)
+{
+       msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
+       msg->msg_data[0] = err;
+       msg->msg.netfn |= 1; /* Convert to a response. */
+       msg->msg.data_len = 1;
+       msg->msg.data = msg->msg_data;
+       deliver_response(msg);
+}
+
 /* Find the next sequence number not being used and add the given
    message with the given timeout to the sequence table.  This must be
    called with the interface's seq_lock held. */
@@ -717,14 +785,8 @@ static int intf_err_seq(ipmi_smi_t   intf,
        }
        spin_unlock_irqrestore(&(intf->seq_lock), flags);
 
-       if (msg) {
-               msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
-               msg->msg_data[0] = err;
-               msg->msg.netfn |= 1; /* Convert to a response. */
-               msg->msg.data_len = 1;
-               msg->msg.data = msg->msg_data;
-               deliver_response(msg);
-       }
+       if (msg)
+               deliver_err_response(msg, err);
 
        return rv;
 }
@@ -766,17 +828,18 @@ int ipmi_create_user(unsigned int          if_num,
        if (!new_user)
                return -ENOMEM;
 
-       spin_lock_irqsave(&interfaces_lock, flags);
-       intf = ipmi_interfaces[if_num];
-       if ((if_num >= MAX_IPMI_INTERFACES) || IPMI_INVALID_INTERFACE(intf)) {
-               spin_unlock_irqrestore(&interfaces_lock, flags);
-               rv = -EINVAL;
-               goto out_kfree;
+       mutex_lock(&ipmi_interfaces_mutex);
+       list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
+               if (intf->intf_num == if_num)
+                       goto found;
        }
+       /* Not found, return an error */
+       rv = -EINVAL;
+       goto out_kfree;
 
+ found:
        /* Note that each existing user holds a refcount to the interface. */
        kref_get(&intf->refcount);
-       spin_unlock_irqrestore(&interfaces_lock, flags);
 
        kref_init(&new_user->refcount);
        new_user->handler = handler;
@@ -797,6 +860,10 @@ int ipmi_create_user(unsigned int          if_num,
                }
        }
 
+       /* Hold the lock so intf->handlers is guaranteed to be good
+        * until now */
+       mutex_unlock(&ipmi_interfaces_mutex);
+
        new_user->valid = 1;
        spin_lock_irqsave(&intf->seq_lock, flags);
        list_add_rcu(&new_user->link, &intf->users);
@@ -807,6 +874,7 @@ int ipmi_create_user(unsigned int          if_num,
 out_kref:
        kref_put(&intf->refcount, intf_free);
 out_kfree:
+       mutex_unlock(&ipmi_interfaces_mutex);
        kfree(new_user);
        return rv;
 }
@@ -836,6 +904,7 @@ int ipmi_destroy_user(ipmi_user_t user)
                    && (intf->seq_table[i].recv_msg->user == user))
                {
                        intf->seq_table[i].inuse = 0;
+                       ipmi_free_recv_msg(intf->seq_table[i].recv_msg);
                }
        }
        spin_unlock_irqrestore(&intf->seq_lock, flags);
@@ -862,9 +931,13 @@ int ipmi_destroy_user(ipmi_user_t user)
                kfree(rcvr);
        }
 
-       module_put(intf->handlers->owner);
-       if (intf->handlers->dec_usecount)
-               intf->handlers->dec_usecount(intf->send_info);
+       mutex_lock(&ipmi_interfaces_mutex);
+       if (intf->handlers) {
+               module_put(intf->handlers->owner);
+               if (intf->handlers->dec_usecount)
+                       intf->handlers->dec_usecount(intf->send_info);
+       }
+       mutex_unlock(&ipmi_interfaces_mutex);
 
        kref_put(&intf->refcount, intf_free);
 
@@ -877,8 +950,8 @@ void ipmi_get_version(ipmi_user_t   user,
                      unsigned char *major,
                      unsigned char *minor)
 {
-       *major = ipmi_version_major(&user->intf->bmc->id);
-       *minor = ipmi_version_minor(&user->intf->bmc->id);
+       *major = user->intf->ipmi_version_major;
+       *minor = user->intf->ipmi_version_minor;
 }
 
 int ipmi_set_my_address(ipmi_user_t   user,
@@ -921,6 +994,65 @@ int ipmi_get_my_LUN(ipmi_user_t   user,
        return 0;
 }
 
+int ipmi_get_maintenance_mode(ipmi_user_t user)
+{
+       int           mode;
+       unsigned long flags;
+
+       spin_lock_irqsave(&user->intf->maintenance_mode_lock, flags);
+       mode = user->intf->maintenance_mode;
+       spin_unlock_irqrestore(&user->intf->maintenance_mode_lock, flags);
+
+       return mode;
+}
+EXPORT_SYMBOL(ipmi_get_maintenance_mode);
+
+static void maintenance_mode_update(ipmi_smi_t intf)
+{
+       if (intf->handlers->set_maintenance_mode)
+               intf->handlers->set_maintenance_mode(
+                       intf->send_info, intf->maintenance_mode_enable);
+}
+
+int ipmi_set_maintenance_mode(ipmi_user_t user, int mode)
+{
+       int           rv = 0;
+       unsigned long flags;
+       ipmi_smi_t    intf = user->intf;
+
+       spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
+       if (intf->maintenance_mode != mode) {
+               switch (mode) {
+               case IPMI_MAINTENANCE_MODE_AUTO:
+                       intf->maintenance_mode = mode;
+                       intf->maintenance_mode_enable
+                               = (intf->auto_maintenance_timeout > 0);
+                       break;
+
+               case IPMI_MAINTENANCE_MODE_OFF:
+                       intf->maintenance_mode = mode;
+                       intf->maintenance_mode_enable = 0;
+                       break;
+
+               case IPMI_MAINTENANCE_MODE_ON:
+                       intf->maintenance_mode = mode;
+                       intf->maintenance_mode_enable = 1;
+                       break;
+
+               default:
+                       rv = -EINVAL;
+                       goto out_unlock;
+               }
+
+               maintenance_mode_update(intf);
+       }
+ out_unlock:
+       spin_unlock_irqrestore(&intf->maintenance_mode_lock, flags);
+
+       return rv;
+}
+EXPORT_SYMBOL(ipmi_set_maintenance_mode);
+
 int ipmi_set_gets_events(ipmi_user_t user, int val)
 {
        unsigned long        flags;
@@ -933,20 +1065,33 @@ int ipmi_set_gets_events(ipmi_user_t user, int val)
        spin_lock_irqsave(&intf->events_lock, flags);
        user->gets_events = val;
 
-       if (val) {
-               /* Deliver any queued events. */
+       if (intf->delivering_events)
+               /*
+                * Another thread is delivering events for this, so
+                * let it handle any new events.
+                */
+               goto out;
+
+       /* Deliver any queued events. */
+       while (user->gets_events && !list_empty(&intf->waiting_events)) {
                list_for_each_entry_safe(msg, msg2, &intf->waiting_events, link)
                        list_move_tail(&msg->link, &msgs);
                intf->waiting_events_count = 0;
-       }
 
-       /* Hold the events lock while doing this to preserve order. */
-       list_for_each_entry_safe(msg, msg2, &msgs, link) {
-               msg->user = user;
-               kref_get(&user->refcount);
-               deliver_response(msg);
+               intf->delivering_events = 1;
+               spin_unlock_irqrestore(&intf->events_lock, flags);
+
+               list_for_each_entry_safe(msg, msg2, &msgs, link) {
+                       msg->user = user;
+                       kref_get(&user->refcount);
+                       deliver_response(msg);
+               }
+
+               spin_lock_irqsave(&intf->events_lock, flags);
+               intf->delivering_events = 0;
        }
 
+ out:
        spin_unlock_irqrestore(&intf->events_lock, flags);
 
        return 0;
@@ -1057,7 +1202,8 @@ int ipmi_unregister_for_cmd(ipmi_user_t   user,
 void ipmi_user_set_run_to_completion(ipmi_user_t user, int val)
 {
        ipmi_smi_t intf = user->intf;
-       intf->handlers->set_run_to_completion(intf->send_info, val);
+       if (intf->handlers)
+               intf->handlers->set_run_to_completion(intf->send_info, val);
 }
 
 static unsigned char
@@ -1168,10 +1314,11 @@ static int i_ipmi_request(ipmi_user_t          user,
                          int                  retries,
                          unsigned int         retry_time_ms)
 {
-       int                  rv = 0;
-       struct ipmi_smi_msg  *smi_msg;
-       struct ipmi_recv_msg *recv_msg;
-       unsigned long        flags;
+       int                      rv = 0;
+       struct ipmi_smi_msg      *smi_msg;
+       struct ipmi_recv_msg     *recv_msg;
+       unsigned long            flags;
+       struct ipmi_smi_handlers *handlers;
 
 
        if (supplied_recv) {
@@ -1194,6 +1341,13 @@ static int i_ipmi_request(ipmi_user_t          user,
                }
        }
 
+       rcu_read_lock();
+       handlers = intf->handlers;
+       if (!handlers) {
+               rv = -ENODEV;
+               goto out_err;
+       }
+
        recv_msg->user = user;
        if (user)
                kref_get(&user->refcount);
@@ -1236,6 +1390,24 @@ static int i_ipmi_request(ipmi_user_t          user,
                        goto out_err;
                }
 
+               if (((msg->netfn == IPMI_NETFN_APP_REQUEST)
+                     && ((msg->cmd == IPMI_COLD_RESET_CMD)
+                         || (msg->cmd == IPMI_WARM_RESET_CMD)))
+                    || (msg->netfn == IPMI_NETFN_FIRMWARE_REQUEST))
+               {
+                       spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
+                       intf->auto_maintenance_timeout
+                               = IPMI_MAINTENANCE_MODE_TIMEOUT;
+                       if (!intf->maintenance_mode
+                           && !intf->maintenance_mode_enable)
+                       {
+                               intf->maintenance_mode_enable = 1;
+                               maintenance_mode_update(intf);
+                       }
+                       spin_unlock_irqrestore(&intf->maintenance_mode_lock,
+                                              flags);
+               }
+
                if ((msg->data_len + 2) > IPMI_MAX_MSG_LENGTH) {
                        spin_lock_irqsave(&intf->counter_lock, flags);
                        intf->sent_invalid_commands++;
@@ -1510,11 +1682,14 @@ static int i_ipmi_request(ipmi_user_t          user,
                printk("\n");
        }
 #endif
-       intf->handlers->sender(intf->send_info, smi_msg, priority);
+
+       handlers->sender(intf->send_info, smi_msg, priority);
+       rcu_read_unlock();
 
        return 0;
 
  out_err:
+       rcu_read_unlock();
        ipmi_free_smi_msg(smi_msg);
        ipmi_free_recv_msg(recv_msg);
        return rv;
@@ -1594,6 +1769,7 @@ int ipmi_request_supply_msgs(ipmi_user_t          user,
                              -1, 0);
 }
 
+#ifdef CONFIG_PROC_FS
 static int ipmb_file_read_proc(char *page, char **start, off_t off,
                               int count, int *eof, void *data)
 {
@@ -1682,6 +1858,7 @@ static int stat_file_read_proc(char *page, char **start, off_t off,
 
        return (out - ((char *) page));
 }
+#endif /* CONFIG_PROC_FS */
 
 int ipmi_smi_add_proc_entry(ipmi_smi_t smi, char *name,
                            read_proc_t *read_proc, write_proc_t *write_proc,
@@ -1807,13 +1984,12 @@ static int __find_bmc_prod_dev_id(struct device *dev, void *data)
        struct bmc_device *bmc = dev_get_drvdata(dev);
 
        return (bmc->id.product_id == id->product_id
-               && bmc->id.product_id == id->product_id
                && bmc->id.device_id == id->device_id);
 }
 
 static struct bmc_device *ipmi_find_bmc_prod_dev_id(
        struct device_driver *drv,
-       unsigned char product_id, unsigned char device_id)
+       unsigned int product_id, unsigned char device_id)
 {
        struct prod_dev_id id = {
                .product_id = product_id,
@@ -1844,7 +2020,7 @@ static ssize_t provides_dev_sdrs_show(struct device *dev,
        struct bmc_device *bmc = dev_get_drvdata(dev);
 
        return snprintf(buf, 10, "%u\n",
-                       bmc->id.device_revision && 0x80 >> 7);
+                       (bmc->id.device_revision & 0x80) >> 7);
 }
 
 static ssize_t revision_show(struct device *dev, struct device_attribute *attr,
@@ -1853,7 +2029,7 @@ static ssize_t revision_show(struct device *dev, struct device_attribute *attr,
        struct bmc_device *bmc = dev_get_drvdata(dev);
 
        return snprintf(buf, 20, "%u\n",
-                       bmc->id.device_revision && 0x0F);
+                       bmc->id.device_revision & 0x0F);
 }
 
 static ssize_t firmware_rev_show(struct device *dev,
@@ -1930,6 +2106,9 @@ static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
 
 static void remove_files(struct bmc_device *bmc)
 {
+       if (!bmc->dev)
+               return;
+
        device_remove_file(&bmc->dev->dev,
                           &bmc->device_id_attr);
        device_remove_file(&bmc->dev->dev,
@@ -1971,7 +2150,11 @@ static void ipmi_bmc_unregister(ipmi_smi_t intf)
 {
        struct bmc_device *bmc = intf->bmc;
 
-       sysfs_remove_link(&intf->si_dev->kobj, "bmc");
+       if (intf->sysfs_name) {
+               sysfs_remove_link(&intf->si_dev->kobj, intf->sysfs_name);
+               kfree(intf->sysfs_name);
+               intf->sysfs_name = NULL;
+       }
        if (intf->my_dev_name) {
                sysfs_remove_link(&bmc->dev->dev.kobj, intf->my_dev_name);
                kfree(intf->my_dev_name);
@@ -1980,6 +2163,7 @@ static void ipmi_bmc_unregister(ipmi_smi_t intf)
 
        mutex_lock(&ipmidriver_mutex);
        kref_put(&bmc->refcount, cleanup_bmc_device);
+       intf->bmc = NULL;
        mutex_unlock(&ipmidriver_mutex);
 }
 
@@ -1987,6 +2171,56 @@ static int create_files(struct bmc_device *bmc)
 {
        int err;
 
+       bmc->device_id_attr.attr.name = "device_id";
+       bmc->device_id_attr.attr.owner = THIS_MODULE;
+       bmc->device_id_attr.attr.mode = S_IRUGO;
+       bmc->device_id_attr.show = device_id_show;
+
+       bmc->provides_dev_sdrs_attr.attr.name = "provides_device_sdrs";
+       bmc->provides_dev_sdrs_attr.attr.owner = THIS_MODULE;
+       bmc->provides_dev_sdrs_attr.attr.mode = S_IRUGO;
+       bmc->provides_dev_sdrs_attr.show = provides_dev_sdrs_show;
+
+       bmc->revision_attr.attr.name = "revision";
+       bmc->revision_attr.attr.owner = THIS_MODULE;
+       bmc->revision_attr.attr.mode = S_IRUGO;
+       bmc->revision_attr.show = revision_show;
+
+       bmc->firmware_rev_attr.attr.name = "firmware_revision";
+       bmc->firmware_rev_attr.attr.owner = THIS_MODULE;
+       bmc->firmware_rev_attr.attr.mode = S_IRUGO;
+       bmc->firmware_rev_attr.show = firmware_rev_show;
+
+       bmc->version_attr.attr.name = "ipmi_version";
+       bmc->version_attr.attr.owner = THIS_MODULE;
+       bmc->version_attr.attr.mode = S_IRUGO;
+       bmc->version_attr.show = ipmi_version_show;
+
+       bmc->add_dev_support_attr.attr.name = "additional_device_support";
+       bmc->add_dev_support_attr.attr.owner = THIS_MODULE;
+       bmc->add_dev_support_attr.attr.mode = S_IRUGO;
+       bmc->add_dev_support_attr.show = add_dev_support_show;
+
+       bmc->manufacturer_id_attr.attr.name = "manufacturer_id";
+       bmc->manufacturer_id_attr.attr.owner = THIS_MODULE;
+       bmc->manufacturer_id_attr.attr.mode = S_IRUGO;
+       bmc->manufacturer_id_attr.show = manufacturer_id_show;
+
+       bmc->product_id_attr.attr.name = "product_id";
+       bmc->product_id_attr.attr.owner = THIS_MODULE;
+       bmc->product_id_attr.attr.mode = S_IRUGO;
+       bmc->product_id_attr.show = product_id_show;
+
+       bmc->guid_attr.attr.name = "guid";
+       bmc->guid_attr.attr.owner = THIS_MODULE;
+       bmc->guid_attr.attr.mode = S_IRUGO;
+       bmc->guid_attr.show = guid_show;
+
+       bmc->aux_firmware_rev_attr.attr.name = "aux_firmware_revision";
+       bmc->aux_firmware_rev_attr.attr.owner = THIS_MODULE;
+       bmc->aux_firmware_rev_attr.attr.mode = S_IRUGO;
+       bmc->aux_firmware_rev_attr.show = aux_firmware_rev_show;
+
        err = device_create_file(&bmc->dev->dev,
                           &bmc->device_id_attr);
        if (err) goto out;
@@ -2056,7 +2290,8 @@ out:
        return err;
 }
 
-static int ipmi_bmc_register(ipmi_smi_t intf)
+static int ipmi_bmc_register(ipmi_smi_t intf, int ifnum,
+                            const char *sysfs_name)
 {
        int               rv;
        struct bmc_device *bmc = intf->bmc;
@@ -2096,9 +2331,38 @@ static int ipmi_bmc_register(ipmi_smi_t intf)
                       bmc->id.product_id,
                       bmc->id.device_id);
        } else {
-               bmc->dev = platform_device_alloc("ipmi_bmc",
-                                                bmc->id.device_id);
+               char name[14];
+               unsigned char orig_dev_id = bmc->id.device_id;
+               int warn_printed = 0;
+
+               snprintf(name, sizeof(name),
+                        "ipmi_bmc.%4.4x", bmc->id.product_id);
+
+               while (ipmi_find_bmc_prod_dev_id(&ipmidriver,
+                                                bmc->id.product_id,
+                                                bmc->id.device_id)) {
+                       if (!warn_printed) {
+                               printk(KERN_WARNING PFX
+                                      "This machine has two different BMCs"
+                                      " with the same product id and device"
+                                      " id.  This is an error in the"
+                                      " firmware, but incrementing the"
+                                      " device id to work around the problem."
+                                      " Prod ID = 0x%x, Dev ID = 0x%x\n",
+                                      bmc->id.product_id, bmc->id.device_id);
+                               warn_printed = 1;
+                       }
+                       bmc->id.device_id++; /* Wraps at 255 */
+                       if (bmc->id.device_id == orig_dev_id) {
+                               printk(KERN_ERR PFX
+                                      "Out of device ids!\n");
+                               break;
+                       }
+               }
+
+               bmc->dev = platform_device_alloc(name, bmc->id.device_id);
                if (!bmc->dev) {
+                       mutex_unlock(&ipmidriver_mutex);
                        printk(KERN_ERR
                               "ipmi_msghandler:"
                               " Unable to allocate platform device\n");
@@ -2108,9 +2372,11 @@ static int ipmi_bmc_register(ipmi_smi_t intf)
                dev_set_drvdata(&bmc->dev->dev, bmc);
                kref_init(&bmc->refcount);
 
-               rv = platform_device_register(bmc->dev);
+               rv = platform_device_add(bmc->dev);
                mutex_unlock(&ipmidriver_mutex);
                if (rv) {
+                       platform_device_put(bmc->dev);
+                       bmc->dev = NULL;
                        printk(KERN_ERR
                               "ipmi_msghandler:"
                               " Unable to register bmc device: %d\n",
@@ -2120,57 +2386,6 @@ static int ipmi_bmc_register(ipmi_smi_t intf)
                        return rv;
                }
 
-               bmc->device_id_attr.attr.name = "device_id";
-               bmc->device_id_attr.attr.owner = THIS_MODULE;
-               bmc->device_id_attr.attr.mode = S_IRUGO;
-               bmc->device_id_attr.show = device_id_show;
-
-               bmc->provides_dev_sdrs_attr.attr.name = "provides_device_sdrs";
-               bmc->provides_dev_sdrs_attr.attr.owner = THIS_MODULE;
-               bmc->provides_dev_sdrs_attr.attr.mode = S_IRUGO;
-               bmc->provides_dev_sdrs_attr.show = provides_dev_sdrs_show;
-
-               bmc->revision_attr.attr.name = "revision";
-               bmc->revision_attr.attr.owner = THIS_MODULE;
-               bmc->revision_attr.attr.mode = S_IRUGO;
-               bmc->revision_attr.show = revision_show;
-
-               bmc->firmware_rev_attr.attr.name = "firmware_revision";
-               bmc->firmware_rev_attr.attr.owner = THIS_MODULE;
-               bmc->firmware_rev_attr.attr.mode = S_IRUGO;
-               bmc->firmware_rev_attr.show = firmware_rev_show;
-
-               bmc->version_attr.attr.name = "ipmi_version";
-               bmc->version_attr.attr.owner = THIS_MODULE;
-               bmc->version_attr.attr.mode = S_IRUGO;
-               bmc->version_attr.show = ipmi_version_show;
-
-               bmc->add_dev_support_attr.attr.name
-                       = "additional_device_support";
-               bmc->add_dev_support_attr.attr.owner = THIS_MODULE;
-               bmc->add_dev_support_attr.attr.mode = S_IRUGO;
-               bmc->add_dev_support_attr.show = add_dev_support_show;
-
-               bmc->manufacturer_id_attr.attr.name = "manufacturer_id";
-               bmc->manufacturer_id_attr.attr.owner = THIS_MODULE;
-               bmc->manufacturer_id_attr.attr.mode = S_IRUGO;
-               bmc->manufacturer_id_attr.show = manufacturer_id_show;
-
-               bmc->product_id_attr.attr.name = "product_id";
-               bmc->product_id_attr.attr.owner = THIS_MODULE;
-               bmc->product_id_attr.attr.mode = S_IRUGO;
-               bmc->product_id_attr.show = product_id_show;
-
-               bmc->guid_attr.attr.name = "guid";
-               bmc->guid_attr.attr.owner = THIS_MODULE;
-               bmc->guid_attr.attr.mode = S_IRUGO;
-               bmc->guid_attr.show = guid_show;
-
-               bmc->aux_firmware_rev_attr.attr.name = "aux_firmware_revision";
-               bmc->aux_firmware_rev_attr.attr.owner = THIS_MODULE;
-               bmc->aux_firmware_rev_attr.attr.mode = S_IRUGO;
-               bmc->aux_firmware_rev_attr.show = aux_firmware_rev_show;
-
                rv = create_files(bmc);
                if (rv) {
                        mutex_lock(&ipmidriver_mutex);
@@ -2192,29 +2407,44 @@ static int ipmi_bmc_register(ipmi_smi_t intf)
         * create symlink from system interface device to bmc device
         * and back.
         */
+       intf->sysfs_name = kstrdup(sysfs_name, GFP_KERNEL);
+       if (!intf->sysfs_name) {
+               rv = -ENOMEM;
+               printk(KERN_ERR
+                      "ipmi_msghandler: allocate link to BMC: %d\n",
+                      rv);
+               goto out_err;
+       }
+
        rv = sysfs_create_link(&intf->si_dev->kobj,
-                              &bmc->dev->dev.kobj, "bmc");
+                              &bmc->dev->dev.kobj, intf->sysfs_name);
        if (rv) {
+               kfree(intf->sysfs_name);
+               intf->sysfs_name = NULL;
                printk(KERN_ERR
                       "ipmi_msghandler: Unable to create bmc symlink: %d\n",
                       rv);
                goto out_err;
        }
 
-       size = snprintf(dummy, 0, "ipmi%d", intf->intf_num);
+       size = snprintf(dummy, 0, "ipmi%d", ifnum);
        intf->my_dev_name = kmalloc(size+1, GFP_KERNEL);
        if (!intf->my_dev_name) {
+               kfree(intf->sysfs_name);
+               intf->sysfs_name = NULL;
                rv = -ENOMEM;
                printk(KERN_ERR
                       "ipmi_msghandler: allocate link from BMC: %d\n",
                       rv);
                goto out_err;
        }
-       snprintf(intf->my_dev_name, size+1, "ipmi%d", intf->intf_num);
+       snprintf(intf->my_dev_name, size+1, "ipmi%d", ifnum);
 
        rv = sysfs_create_link(&bmc->dev->dev.kobj, &intf->si_dev->kobj,
                               intf->my_dev_name);
        if (rv) {
+               kfree(intf->sysfs_name);
+               intf->sysfs_name = NULL;
                kfree(intf->my_dev_name);
                intf->my_dev_name = NULL;
                printk(KERN_ERR
@@ -2399,17 +2629,14 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers,
                      void                     *send_info,
                      struct ipmi_device_id    *device_id,
                      struct device            *si_dev,
+                     const char               *sysfs_name,
                      unsigned char            slave_addr)
 {
        int              i, j;
        int              rv;
        ipmi_smi_t       intf;
-       unsigned long    flags;
-       int              version_major;
-       int              version_minor;
-
-       version_major = ipmi_version_major(device_id);
-       version_minor = ipmi_version_minor(device_id);
+       ipmi_smi_t       tintf;
+       struct list_head *link;
 
        /* Make sure the driver is actually initialized, this handles
           problems with initialization order. */
@@ -2427,12 +2654,16 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers,
        if (!intf)
                return -ENOMEM;
        memset(intf, 0, sizeof(*intf));
+
+       intf->ipmi_version_major = ipmi_version_major(device_id);
+       intf->ipmi_version_minor = ipmi_version_minor(device_id);
+
        intf->bmc = kzalloc(sizeof(*intf->bmc), GFP_KERNEL);
        if (!intf->bmc) {
                kfree(intf);
                return -ENOMEM;
        }
-       intf->intf_num = -1;
+       intf->intf_num = -1; /* Mark it invalid for now. */
        kref_init(&intf->refcount);
        intf->bmc->id = *device_id;
        intf->si_dev = si_dev;
@@ -2460,26 +2691,30 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers,
        INIT_LIST_HEAD(&intf->waiting_events);
        intf->waiting_events_count = 0;
        mutex_init(&intf->cmd_rcvrs_mutex);
+       spin_lock_init(&intf->maintenance_mode_lock);
        INIT_LIST_HEAD(&intf->cmd_rcvrs);
        init_waitqueue_head(&intf->waitq);
 
        spin_lock_init(&intf->counter_lock);
        intf->proc_dir = NULL;
 
-       rv = -ENOMEM;
-       spin_lock_irqsave(&interfaces_lock, flags);
-       for (i = 0; i < MAX_IPMI_INTERFACES; i++) {
-               if (ipmi_interfaces[i] == NULL) {
-                       intf->intf_num = i;
-                       /* Reserve the entry till we are done. */
-                       ipmi_interfaces[i] = IPMI_INVALID_INTERFACE_ENTRY;
-                       rv = 0;
+       mutex_lock(&smi_watchers_mutex);
+       mutex_lock(&ipmi_interfaces_mutex);
+       /* Look for a hole in the numbers. */
+       i = 0;
+       link = &ipmi_interfaces;
+       list_for_each_entry_rcu(tintf, &ipmi_interfaces, link) {
+               if (tintf->intf_num != i) {
+                       link = &tintf->link;
                        break;
                }
+               i++;
        }
-       spin_unlock_irqrestore(&interfaces_lock, flags);
-       if (rv)
-               goto out;
+       /* Add the new interface in numeric order. */
+       if (i == 0)
+               list_add_rcu(&intf->link, &ipmi_interfaces);
+       else
+               list_add_tail_rcu(&intf->link, link);
 
        rv = handlers->start_processing(send_info, intf);
        if (rv)
@@ -2487,8 +2722,9 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers,
 
        get_guid(intf);
 
-       if ((version_major > 1)
-           || ((version_major == 1) && (version_minor >= 5)))
+       if ((intf->ipmi_version_major > 1)
+           || ((intf->ipmi_version_major == 1)
+               && (intf->ipmi_version_minor >= 5)))
        {
                /* Start scanning the channels to see what is
                   available. */
@@ -2511,64 +2747,67 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers,
        if (rv == 0)
                rv = add_proc_entries(intf, i);
 
-       rv = ipmi_bmc_register(intf);
+       rv = ipmi_bmc_register(intf, i, sysfs_name);
 
  out:
        if (rv) {
                if (intf->proc_dir)
                        remove_proc_entries(intf);
+               intf->handlers = NULL;
+               list_del_rcu(&intf->link);
+               mutex_unlock(&ipmi_interfaces_mutex);
+               mutex_unlock(&smi_watchers_mutex);
+               synchronize_rcu();
                kref_put(&intf->refcount, intf_free);
-               if (i < MAX_IPMI_INTERFACES) {
-                       spin_lock_irqsave(&interfaces_lock, flags);
-                       ipmi_interfaces[i] = NULL;
-                       spin_unlock_irqrestore(&interfaces_lock, flags);
-               }
        } else {
-               spin_lock_irqsave(&interfaces_lock, flags);
-               ipmi_interfaces[i] = intf;
-               spin_unlock_irqrestore(&interfaces_lock, flags);
+               /* After this point the interface is legal to use. */
+               intf->intf_num = i;
+               mutex_unlock(&ipmi_interfaces_mutex);
                call_smi_watchers(i, intf->si_dev);
+               mutex_unlock(&smi_watchers_mutex);
        }
 
        return rv;
 }
 
+static void cleanup_smi_msgs(ipmi_smi_t intf)
+{
+       int              i;
+       struct seq_table *ent;
+
+       /* No need for locks, the interface is down. */
+       for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) {
+               ent = &(intf->seq_table[i]);
+               if (!ent->inuse)
+                       continue;
+               deliver_err_response(ent->recv_msg, IPMI_ERR_UNSPECIFIED);
+       }
+}
+
 int ipmi_unregister_smi(ipmi_smi_t intf)
 {
-       int                     i;
        struct ipmi_smi_watcher *w;
-       unsigned long           flags;
+       int    intf_num = intf->intf_num;
 
        ipmi_bmc_unregister(intf);
 
-       spin_lock_irqsave(&interfaces_lock, flags);
-       for (i = 0; i < MAX_IPMI_INTERFACES; i++) {
-               if (ipmi_interfaces[i] == intf) {
-                       /* Set the interface number reserved until we
-                        * are done. */
-                       ipmi_interfaces[i] = IPMI_INVALID_INTERFACE_ENTRY;
-                       intf->intf_num = -1;
-                       break;
-               }
-       }
-       spin_unlock_irqrestore(&interfaces_lock,flags);
+       mutex_lock(&smi_watchers_mutex);
+       mutex_lock(&ipmi_interfaces_mutex);
+       intf->intf_num = -1;
+       intf->handlers = NULL;
+       list_del_rcu(&intf->link);
+       mutex_unlock(&ipmi_interfaces_mutex);
+       synchronize_rcu();
 
-       if (i == MAX_IPMI_INTERFACES)
-               return -ENODEV;
+       cleanup_smi_msgs(intf);
 
        remove_proc_entries(intf);
 
        /* Call all the watcher interfaces to tell them that
           an interface is gone. */
-       down_read(&smi_watchers_sem);
        list_for_each_entry(w, &smi_watchers, link)
-               w->smi_gone(i);
-       up_read(&smi_watchers_sem);
-
-       /* Allow the entry to be reused now. */
-       spin_lock_irqsave(&interfaces_lock, flags);
-       ipmi_interfaces[i] = NULL;
-       spin_unlock_irqrestore(&interfaces_lock,flags);
+               w->smi_gone(intf_num);
+       mutex_unlock(&smi_watchers_mutex);
 
        kref_put(&intf->refcount, intf_free);
        return 0;
@@ -2650,6 +2889,7 @@ static int handle_ipmb_get_msg_cmd(ipmi_smi_t          intf,
        struct ipmi_ipmb_addr    *ipmb_addr;
        struct ipmi_recv_msg     *recv_msg;
        unsigned long            flags;
+       struct ipmi_smi_handlers *handlers;
 
        if (msg->rsp_size < 10) {
                /* Message not big enough, just ignore it. */
@@ -2706,10 +2946,16 @@ static int handle_ipmb_get_msg_cmd(ipmi_smi_t          intf,
                printk("\n");
        }
 #endif
-               intf->handlers->sender(intf->send_info, msg, 0);
-
-               rv = -1; /* We used the message, so return the value that
-                           causes it to not be freed or queued. */
+               rcu_read_lock();
+               handlers = intf->handlers;
+               if (handlers) {
+                       handlers->sender(intf->send_info, msg, 0);
+                       /* We used the message, so return the value
+                          that causes it to not be freed or
+                          queued. */
+                       rv = -1;
+               }
+               rcu_read_unlock();
        } else {
                /* Deliver the message to the user. */
                spin_lock_irqsave(&intf->counter_lock, flags);
@@ -3232,7 +3478,9 @@ void ipmi_smi_msg_received(ipmi_smi_t          intf,
                    report the error immediately. */
                if ((msg->rsp_size >= 3) && (msg->rsp[2] != 0)
                    && (msg->rsp[2] != IPMI_NODE_BUSY_ERR)
-                   && (msg->rsp[2] != IPMI_LOST_ARBITRATION_ERR))
+                   && (msg->rsp[2] != IPMI_LOST_ARBITRATION_ERR)
+                   && (msg->rsp[2] != IPMI_BUS_ERR)
+                   && (msg->rsp[2] != IPMI_NAK_ON_WRITE_ERR))
                {
                        int chan = msg->rsp[3] & 0xf;
 
@@ -3297,16 +3545,6 @@ void ipmi_smi_watchdog_pretimeout(ipmi_smi_t intf)
        rcu_read_unlock();
 }
 
-static void
-handle_msg_timeout(struct ipmi_recv_msg *msg)
-{
-       msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
-       msg->msg_data[0] = IPMI_TIMEOUT_COMPLETION_CODE;
-       msg->msg.netfn |= 1; /* Convert to a response. */
-       msg->msg.data_len = 1;
-       msg->msg.data = msg->msg_data;
-       deliver_response(msg);
-}
 
 static struct ipmi_smi_msg *
 smi_from_recv_msg(ipmi_smi_t intf, struct ipmi_recv_msg *recv_msg,
@@ -3338,7 +3576,11 @@ static void check_msg_timeout(ipmi_smi_t intf, struct seq_table *ent,
                              struct list_head *timeouts, long timeout_period,
                              int slot, unsigned long *flags)
 {
-       struct ipmi_recv_msg *msg;
+       struct ipmi_recv_msg     *msg;
+       struct ipmi_smi_handlers *handlers;
+
+       if (intf->intf_num == -1)
+               return;
 
        if (!ent->inuse)
                return;
@@ -3381,13 +3623,19 @@ static void check_msg_timeout(ipmi_smi_t intf, struct seq_table *ent,
                        return;
 
                spin_unlock_irqrestore(&intf->seq_lock, *flags);
+
                /* Send the new message.  We send with a zero
                 * priority.  It timed out, I doubt time is
                 * that critical now, and high priority
                 * messages are really only for messages to the
                 * local MC, which don't get resent. */
-               intf->handlers->sender(intf->send_info,
-                                      smi_msg, 0);
+               handlers = intf->handlers;
+               if (handlers)
+                       intf->handlers->sender(intf->send_info,
+                                              smi_msg, 0);
+               else
+                       ipmi_free_smi_msg(smi_msg);
+
                spin_lock_irqsave(&intf->seq_lock, *flags);
        }
 }
@@ -3399,18 +3647,10 @@ static void ipmi_timeout_handler(long timeout_period)
        struct ipmi_recv_msg *msg, *msg2;
        struct ipmi_smi_msg  *smi_msg, *smi_msg2;
        unsigned long        flags;
-       int                  i, j;
-
-       INIT_LIST_HEAD(&timeouts);
-
-       spin_lock(&interfaces_lock);
-       for (i = 0; i < MAX_IPMI_INTERFACES; i++) {
-               intf = ipmi_interfaces[i];
-               if (IPMI_INVALID_INTERFACE(intf))
-                       continue;
-               kref_get(&intf->refcount);
-               spin_unlock(&interfaces_lock);
+       int                  i;
 
+       rcu_read_lock();
+       list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
                /* See if any waiting messages need to be processed. */
                spin_lock_irqsave(&intf->waiting_msgs_lock, flags);
                list_for_each_entry_safe(smi_msg, smi_msg2,
@@ -3429,36 +3669,62 @@ static void ipmi_timeout_handler(long timeout_period)
                /* Go through the seq table and find any messages that
                   have timed out, putting them in the timeouts
                   list. */
+               INIT_LIST_HEAD(&timeouts);
                spin_lock_irqsave(&intf->seq_lock, flags);
-               for (j = 0; j < IPMI_IPMB_NUM_SEQ; j++)
-                       check_msg_timeout(intf, &(intf->seq_table[j]),
-                                         &timeouts, timeout_period, j,
+               for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++)
+                       check_msg_timeout(intf, &(intf->seq_table[i]),
+                                         &timeouts, timeout_period, i,
                                          &flags);
                spin_unlock_irqrestore(&intf->seq_lock, flags);
 
                list_for_each_entry_safe(msg, msg2, &timeouts, link)
-                       handle_msg_timeout(msg);
-
-               kref_put(&intf->refcount, intf_free);
-               spin_lock(&interfaces_lock);
+                       deliver_err_response(msg, IPMI_TIMEOUT_COMPLETION_CODE);
+
+               /*
+                * Maintenance mode handling.  Check the timeout
+                * optimistically before we claim the lock.  It may
+                * mean a timeout gets missed occasionally, but that
+                * only means the timeout gets extended by one period
+                * in that case.  No big deal, and it avoids the lock
+                * most of the time.
+                */
+               if (intf->auto_maintenance_timeout > 0) {
+                       spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
+                       if (intf->auto_maintenance_timeout > 0) {
+                               intf->auto_maintenance_timeout
+                                       -= timeout_period;
+                               if (!intf->maintenance_mode
+                                   && (intf->auto_maintenance_timeout <= 0))
+                               {
+                                       intf->maintenance_mode_enable = 0;
+                                       maintenance_mode_update(intf);
+                               }
+                       }
+                       spin_unlock_irqrestore(&intf->maintenance_mode_lock,
+                                              flags);
+               }
        }
-       spin_unlock(&interfaces_lock);
+       rcu_read_unlock();
 }
 
 static void ipmi_request_event(void)
 {
-       ipmi_smi_t intf;
-       int        i;
+       ipmi_smi_t               intf;
+       struct ipmi_smi_handlers *handlers;
 
-       spin_lock(&interfaces_lock);
-       for (i = 0; i < MAX_IPMI_INTERFACES; i++) {
-               intf = ipmi_interfaces[i];
-               if (IPMI_INVALID_INTERFACE(intf))
+       rcu_read_lock();
+       /* Called from the timer, no need to check if handlers is
+        * valid. */
+       list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
+               /* No event requests when in maintenance mode. */
+               if (intf->maintenance_mode_enable)
                        continue;
 
-               intf->handlers->request_events(intf->send_info);
+               handlers = intf->handlers;
+               if (handlers)
+                       handlers->request_events(intf->send_info);
        }
-       spin_unlock(&interfaces_lock);
+       rcu_read_unlock();
 }
 
 static struct timer_list ipmi_timer;
@@ -3587,7 +3853,6 @@ static void send_panic_events(char *str)
        struct kernel_ipmi_msg            msg;
        ipmi_smi_t                        intf;
        unsigned char                     data[16];
-       int                               i;
        struct ipmi_system_interface_addr *si;
        struct ipmi_addr                  addr;
        struct ipmi_smi_msg               smi_msg;
@@ -3621,9 +3886,9 @@ static void send_panic_events(char *str)
        recv_msg.done = dummy_recv_done_handler;
 
        /* For every registered interface, send the event. */
-       for (i = 0; i < MAX_IPMI_INTERFACES; i++) {
-               intf = ipmi_interfaces[i];
-               if (IPMI_INVALID_INTERFACE(intf))
+       list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
+               if (!intf->handlers)
+                       /* Interface is not ready. */
                        continue;
 
                /* Send the event announcing the panic. */
@@ -3648,13 +3913,14 @@ static void send_panic_events(char *str)
        if (!str) 
                return;
 
-       for (i = 0; i < MAX_IPMI_INTERFACES; i++) {
+       /* For every registered interface, send the event. */
+       list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
                char                  *p = str;
                struct ipmi_ipmb_addr *ipmb;
                int                   j;
 
-               intf = ipmi_interfaces[i];
-               if (IPMI_INVALID_INTERFACE(intf))
+               if (intf->intf_num == -1)
+                       /* Interface was not ready yet. */
                        continue;
 
                /* First job here is to figure out where to send the
@@ -3774,13 +4040,12 @@ static void send_panic_events(char *str)
 }
 #endif /* CONFIG_IPMI_PANIC_EVENT */
 
-static int has_panicked = 0;
+static int has_panicked;
 
 static int panic_event(struct notifier_block *this,
                       unsigned long         event,
                        void                  *ptr)
 {
-       int        i;
        ipmi_smi_t intf;
 
        if (has_panicked)
@@ -3788,9 +4053,9 @@ static int panic_event(struct notifier_block *this,
        has_panicked = 1;
 
        /* For every registered interface, set it to run to completion. */
-       for (i = 0; i < MAX_IPMI_INTERFACES; i++) {
-               intf = ipmi_interfaces[i];
-               if (IPMI_INVALID_INTERFACE(intf))
+       list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
+               if (!intf->handlers)
+                       /* Interface is not ready. */
                        continue;
 
                intf->handlers->set_run_to_completion(intf->send_info, 1);
@@ -3811,7 +4076,6 @@ static struct notifier_block panic_block = {
 
 static int ipmi_init_msghandler(void)
 {
-       int i;
        int rv;
 
        if (initialized)
@@ -3826,9 +4090,6 @@ static int ipmi_init_msghandler(void)
        printk(KERN_INFO "ipmi message handler version "
               IPMI_DRIVER_VERSION "\n");
 
-       for (i = 0; i < MAX_IPMI_INTERFACES; i++)
-               ipmi_interfaces[i] = NULL;
-
 #ifdef CONFIG_PROC_FS
        proc_ipmi_root = proc_mkdir("ipmi", NULL);
        if (!proc_ipmi_root) {