Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 5172 insertions, 0 deletions

diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
new file mode 100644
index 000000000..4cf3ef4dd
--- /dev/null
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -0,0 +1,5172 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * ipmi_msghandler.c
+ *
+ * Incoming and outgoing message routing for an IPMI interface.
+ *
+ * Author: MontaVista Software, Inc.
+ *         Corey Minyard <minyard@mvista.com>
+ *         source@mvista.com
+ *
+ * Copyright 2002 MontaVista Software Inc.
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/poll.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/ipmi.h>
+#include <linux/ipmi_smi.h>
+#include <linux/notifier.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <linux/rcupdate.h>
+#include <linux/interrupt.h>
+#include <linux/moduleparam.h>
+#include <linux/workqueue.h>
+#include <linux/uuid.h>
+#include <linux/nospec.h>
+#include <linux/vmalloc.h>
+
+#define PFX "IPMI message handler: "
+
+#define IPMI_DRIVER_VERSION "39.2"
+
+static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void);
+static int ipmi_init_msghandler(void);
+static void smi_recv_tasklet(unsigned long);
+static void handle_new_recv_msgs(struct ipmi_smi *intf);
+static void need_waiter(struct ipmi_smi *intf);
+static int handle_one_recv_msg(struct ipmi_smi *intf,
+			       struct ipmi_smi_msg *msg);
+
+#ifdef DEBUG
+static void ipmi_debug_msg(const char *title, unsigned char *data,
+			   unsigned int len)
+{
+	int i, pos;
+	char buf[100];
+
+	pos = snprintf(buf, sizeof(buf), "%s: ", title);
+	for (i = 0; i < len; i++)
+		pos += snprintf(buf + pos, sizeof(buf) - pos,
+				" %2.2x", data[i]);
+	pr_debug("%s\n", buf);
+}
+#else
+static void ipmi_debug_msg(const char *title, unsigned char *data,
+			   unsigned int len)
+{ }
+#endif
+
+static bool initialized;
+static bool drvregistered;
+
+enum ipmi_panic_event_op {
+	IPMI_SEND_PANIC_EVENT_NONE,
+	IPMI_SEND_PANIC_EVENT,
+	IPMI_SEND_PANIC_EVENT_STRING
+};
+#ifdef CONFIG_IPMI_PANIC_STRING
+#define IPMI_PANIC_DEFAULT IPMI_SEND_PANIC_EVENT_STRING
+#elif defined(CONFIG_IPMI_PANIC_EVENT)
+#define IPMI_PANIC_DEFAULT IPMI_SEND_PANIC_EVENT
+#else
+#define IPMI_PANIC_DEFAULT IPMI_SEND_PANIC_EVENT_NONE
+#endif
+static enum ipmi_panic_event_op ipmi_send_panic_event = IPMI_PANIC_DEFAULT;
+
+static int panic_op_write_handler(const char *val,
+				  const struct kernel_param *kp)
+{
+	char valcp[16];
+	char *s;
+
+	strncpy(valcp, val, 15);
+	valcp[15] = '\0';
+
+	s = strstrip(valcp);
+
+	if (strcmp(s, "none") == 0)
+		ipmi_send_panic_event = IPMI_SEND_PANIC_EVENT_NONE;
+	else if (strcmp(s, "event") == 0)
+		ipmi_send_panic_event = IPMI_SEND_PANIC_EVENT;
+	else if (strcmp(s, "string") == 0)
+		ipmi_send_panic_event = IPMI_SEND_PANIC_EVENT_STRING;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+static int panic_op_read_handler(char *buffer, const struct kernel_param *kp)
+{
+	switch (ipmi_send_panic_event) {
+	case IPMI_SEND_PANIC_EVENT_NONE:
+		strcpy(buffer, "none");
+		break;
+
+	case IPMI_SEND_PANIC_EVENT:
+		strcpy(buffer, "event");
+		break;
+
+	case IPMI_SEND_PANIC_EVENT_STRING:
+		strcpy(buffer, "string");
+		break;
+
+	default:
+		strcpy(buffer, "???");
+		break;
+	}
+
+	return strlen(buffer);
+}
+
+static const struct kernel_param_ops panic_op_ops = {
+	.set = panic_op_write_handler,
+	.get = panic_op_read_handler
+};
+module_param_cb(panic_op, &panic_op_ops, NULL, 0600);
+MODULE_PARM_DESC(panic_op, "Sets if the IPMI driver will attempt to store panic information in the event log in the event of a panic.  Set to 'none' for no, 'event' for a single event, or 'string' for a generic event and the panic string in IPMI OEM events.");
+
+
+#define MAX_EVENTS_IN_QUEUE	25
+
+/* Remain in auto-maintenance mode for this amount of time (in ms). */
+static unsigned long maintenance_mode_timeout_ms = 30000;
+module_param(maintenance_mode_timeout_ms, ulong, 0644);
+MODULE_PARM_DESC(maintenance_mode_timeout_ms,
+		 "The time (milliseconds) after the last maintenance message that the connection stays in maintenance mode.");
+
+/*
+ * Don't let a message sit in a queue forever, always time it with at lest
+ * the max message timer.  This is in milliseconds.
+ */
+#define MAX_MSG_TIMEOUT		60000
+
+/*
+ * Timeout times below are in milliseconds, and are done off a 1
+ * second timer.  So setting the value to 1000 would mean anything
+ * between 0 and 1000ms.  So really the only reasonable minimum
+ * setting it 2000ms, which is between 1 and 2 seconds.
+ */
+
+/* The default timeout for message retries. */
+static unsigned long default_retry_ms = 2000;
+module_param(default_retry_ms, ulong, 0644);
+MODULE_PARM_DESC(default_retry_ms,
+		 "The time (milliseconds) between retry sends");
+
+/* The default timeout for maintenance mode message retries. */
+static unsigned long default_maintenance_retry_ms = 3000;
+module_param(default_maintenance_retry_ms, ulong, 0644);
+MODULE_PARM_DESC(default_maintenance_retry_ms,
+		 "The time (milliseconds) between retry sends in maintenance mode");
+
+/* The default maximum number of retries */
+static unsigned int default_max_retries = 4;
+module_param(default_max_retries, uint, 0644);
+MODULE_PARM_DESC(default_max_retries,
+		 "The time (milliseconds) between retry sends in maintenance mode");
+
+/* Call every ~1000 ms. */
+#define IPMI_TIMEOUT_TIME	1000
+
+/* How many jiffies does it take to get to the timeout time. */
+#define IPMI_TIMEOUT_JIFFIES	((IPMI_TIMEOUT_TIME * HZ) / 1000)
+
+/*
+ * Request events from the queue every second (this is the number of
+ * IPMI_TIMEOUT_TIMES between event requests).  Hopefully, in the
+ * future, IPMI will add a way to know immediately if an event is in
+ * the queue and this silliness can go away.
+ */
+#define IPMI_REQUEST_EV_TIME	(1000 / (IPMI_TIMEOUT_TIME))
+
+/* How long should we cache dynamic device IDs? */
+#define IPMI_DYN_DEV_ID_EXPIRY	(10 * HZ)
+
+/*
+ * The main "user" data structure.
+ */
+struct ipmi_user {
+	struct list_head link;
+
+	/*
+	 * Set to NULL when the user is destroyed, a pointer to myself
+	 * so srcu_dereference can be used on it.
+	 */
+	struct ipmi_user *self;
+	struct srcu_struct release_barrier;
+
+	struct kref refcount;
+
+	/* The upper layer that handles receive messages. */
+	const struct ipmi_user_hndl *handler;
+	void             *handler_data;
+
+	/* The interface this user is bound to. */
+	struct ipmi_smi *intf;
+
+	/* Does this interface receive IPMI events? */
+	bool gets_events;
+
+	/* Free must run in process context for RCU cleanup. */
+	struct work_struct remove_work;
+};
+
+static struct workqueue_struct *remove_work_wq;
+
+static struct ipmi_user *acquire_ipmi_user(struct ipmi_user *user, int *index)
+	__acquires(user->release_barrier)
+{
+	struct ipmi_user *ruser;
+
+	*index = srcu_read_lock(&user->release_barrier);
+	ruser = srcu_dereference(user->self, &user->release_barrier);
+	if (!ruser)
+		srcu_read_unlock(&user->release_barrier, *index);
+	return ruser;
+}
+
+static void release_ipmi_user(struct ipmi_user *user, int index)
+{
+	srcu_read_unlock(&user->release_barrier, index);
+}
+
+struct cmd_rcvr {
+	struct list_head link;
+
+	struct ipmi_user *user;
+	unsigned char netfn;
+	unsigned char cmd;
+	unsigned int  chans;
+
+	/*
+	 * This is used to form a linked lised during mass deletion.
+	 * Since this is in an RCU list, we cannot use the link above
+	 * or change any data until the RCU period completes.  So we
+	 * use this next variable during mass deletion so we can have
+	 * a list and don't have to wait and restart the search on
+	 * every individual deletion of a command.
+	 */
+	struct cmd_rcvr *next;
+};
+
+struct seq_table {
+	unsigned int         inuse : 1;
+	unsigned int         broadcast : 1;
+
+	unsigned long        timeout;
+	unsigned long        orig_timeout;
+	unsigned int         retries_left;
+
+	/*
+	 * To verify on an incoming send message response that this is
+	 * the message that the response is for, we keep a sequence id
+	 * and increment it every time we send a message.
+	 */
+	long                 seqid;
+
+	/*
+	 * This is held so we can properly respond to the message on a
+	 * timeout, and it is used to hold the temporary data for
+	 * retransmission, too.
+	 */
+	struct ipmi_recv_msg *recv_msg;
+};
+
+/*
+ * Store the information in a msgid (long) to allow us to find a
+ * sequence table entry from the msgid.
+ */
+#define STORE_SEQ_IN_MSGID(seq, seqid) \
+	((((seq) & 0x3f) << 26) | ((seqid) & 0x3ffffff))
+
+#define GET_SEQ_FROM_MSGID(msgid, seq, seqid) \
+	do {								\
+		seq = (((msgid) >> 26) & 0x3f);				\
+		seqid = ((msgid) & 0x3ffffff);				\
+	} while (0)
+
+#define NEXT_SEQID(seqid) (((seqid) + 1) & 0x3ffffff)
+
+#define IPMI_MAX_CHANNELS       16
+struct ipmi_channel {
+	unsigned char medium;
+	unsigned char protocol;
+};
+
+struct ipmi_channel_set {
+	struct ipmi_channel c[IPMI_MAX_CHANNELS];
+};
+
+struct ipmi_my_addrinfo {
+	/*
+	 * My slave address.  This is initialized to IPMI_BMC_SLAVE_ADDR,
+	 * but may be changed by the user.
+	 */
+	unsigned char address;
+
+	/*
+	 * My LUN.  This should generally stay the SMS LUN, but just in
+	 * case...
+	 */
+	unsigned char lun;
+};
+
+/*
+ * Note that the product id, manufacturer id, guid, and device id are
+ * immutable in this structure, so dyn_mutex is not required for
+ * accessing those.  If those change on a BMC, a new BMC is allocated.
+ */
+struct bmc_device {
+	struct platform_device pdev;
+	struct list_head       intfs; /* Interfaces on this BMC. */
+	struct ipmi_device_id  id;
+	struct ipmi_device_id  fetch_id;
+	int                    dyn_id_set;
+	unsigned long          dyn_id_expiry;
+	struct mutex           dyn_mutex; /* Protects id, intfs, & dyn* */
+	guid_t                 guid;
+	guid_t                 fetch_guid;
+	int                    dyn_guid_set;
+	struct kref	       usecount;
+	struct work_struct     remove_work;
+};
+#define to_bmc_device(x) container_of((x), struct bmc_device, pdev.dev)
+
+static int bmc_get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc,
+			     struct ipmi_device_id *id,
+			     bool *guid_set, guid_t *guid);
+
+/*
+ * Various statistics for IPMI, these index stats[] in the ipmi_smi
+ * structure.
+ */
+enum ipmi_stat_indexes {
+	/* Commands we got from the user that were invalid. */
+	IPMI_STAT_sent_invalid_commands = 0,
+
+	/* Commands we sent to the MC. */
+	IPMI_STAT_sent_local_commands,
+
+	/* Responses from the MC that were delivered to a user. */
+	IPMI_STAT_handled_local_responses,
+
+	/* Responses from the MC that were not delivered to a user. */
+	IPMI_STAT_unhandled_local_responses,
+
+	/* Commands we sent out to the IPMB bus. */
+	IPMI_STAT_sent_ipmb_commands,
+
+	/* Commands sent on the IPMB that had errors on the SEND CMD */
+	IPMI_STAT_sent_ipmb_command_errs,
+
+	/* Each retransmit increments this count. */
+	IPMI_STAT_retransmitted_ipmb_commands,
+
+	/*
+	 * When a message times out (runs out of retransmits) this is
+	 * incremented.
+	 */
+	IPMI_STAT_timed_out_ipmb_commands,
+
+	/*
+	 * This is like above, but for broadcasts.  Broadcasts are
+	 * *not* included in the above count (they are expected to
+	 * time out).
+	 */
+	IPMI_STAT_timed_out_ipmb_broadcasts,
+
+	/* Responses I have sent to the IPMB bus. */
+	IPMI_STAT_sent_ipmb_responses,
+
+	/* The response was delivered to the user. */
+	IPMI_STAT_handled_ipmb_responses,
+
+	/* The response had invalid data in it. */
+	IPMI_STAT_invalid_ipmb_responses,
+
+	/* The response didn't have anyone waiting for it. */
+	IPMI_STAT_unhandled_ipmb_responses,
+
+	/* Commands we sent out to the IPMB bus. */
+	IPMI_STAT_sent_lan_commands,
+
+	/* Commands sent on the IPMB that had errors on the SEND CMD */
+	IPMI_STAT_sent_lan_command_errs,
+
+	/* Each retransmit increments this count. */
+	IPMI_STAT_retransmitted_lan_commands,
+
+	/*
+	 * When a message times out (runs out of retransmits) this is
+	 * incremented.
+	 */
+	IPMI_STAT_timed_out_lan_commands,
+
+	/* Responses I have sent to the IPMB bus. */
+	IPMI_STAT_sent_lan_responses,
+
+	/* The response was delivered to the user. */
+	IPMI_STAT_handled_lan_responses,
+
+	/* The response had invalid data in it. */
+	IPMI_STAT_invalid_lan_responses,
+
+	/* The response didn't have anyone waiting for it. */
+	IPMI_STAT_unhandled_lan_responses,
+
+	/* The command was delivered to the user. */
+	IPMI_STAT_handled_commands,
+
+	/* The command had invalid data in it. */
+	IPMI_STAT_invalid_commands,
+
+	/* The command didn't have anyone waiting for it. */
+	IPMI_STAT_unhandled_commands,
+
+	/* Invalid data in an event. */
+	IPMI_STAT_invalid_events,
+
+	/* Events that were received with the proper format. */
+	IPMI_STAT_events,
+
+	/* Retransmissions on IPMB that failed. */
+	IPMI_STAT_dropped_rexmit_ipmb_commands,
+
+	/* Retransmissions on LAN that failed. */
+	IPMI_STAT_dropped_rexmit_lan_commands,
+
+	/* This *must* remain last, add new values above this. */
+	IPMI_NUM_STATS
+};
+
+
+#define IPMI_IPMB_NUM_SEQ	64
+struct ipmi_smi {
+	struct module *owner;
+
+	/* What interface number are we? */
+	int intf_num;
+
+	struct kref refcount;
+
+	/* Set when the interface is being unregistered. */
+	bool in_shutdown;
+
+	/* Used for a list of interfaces. */
+	struct list_head link;
+
+	/*
+	 * The list of upper layers that are using me.  seq_lock write
+	 * protects this.  Read protection is with srcu.
+	 */
+	struct list_head users;
+	struct srcu_struct users_srcu;
+
+	/* Used for wake ups at startup. */
+	wait_queue_head_t waitq;
+
+	/*
+	 * Prevents the interface from being unregistered when the
+	 * interface is used by being looked up through the BMC
+	 * structure.
+	 */
+	struct mutex bmc_reg_mutex;
+
+	struct bmc_device tmp_bmc;
+	struct bmc_device *bmc;
+	bool bmc_registered;
+	struct list_head bmc_link;
+	char *my_dev_name;
+	bool in_bmc_register;  /* Handle recursive situations.  Yuck. */
+	struct work_struct bmc_reg_work;
+
+	const struct ipmi_smi_handlers *handlers;
+	void                     *send_info;
+
+	/* Driver-model device for the system interface. */
+	struct device          *si_dev;
+
+	/*
+	 * A table of sequence numbers for this interface.  We use the
+	 * sequence numbers for IPMB messages that go out of the
+	 * interface to match them up with their responses.  A routine
+	 * is called periodically to time the items in this list.
+	 */
+	spinlock_t       seq_lock;
+	struct seq_table seq_table[IPMI_IPMB_NUM_SEQ];
+	int curr_seq;
+
+	/*
+	 * Messages queued for delivery.  If delivery fails (out of memory
+	 * for instance), They will stay in here to be processed later in a
+	 * periodic timer interrupt.  The tasklet is for handling received
+	 * messages directly from the handler.
+	 */
+	spinlock_t       waiting_rcv_msgs_lock;
+	struct list_head waiting_rcv_msgs;
+	atomic_t	 watchdog_pretimeouts_to_deliver;
+	struct tasklet_struct recv_tasklet;
+
+	spinlock_t             xmit_msgs_lock;
+	struct list_head       xmit_msgs;
+	struct ipmi_smi_msg    *curr_msg;
+	struct list_head       hp_xmit_msgs;
+
+	/*
+	 * The list of command receivers that are registered for commands
+	 * on this interface.
+	 */
+	struct mutex     cmd_rcvrs_mutex;
+	struct list_head cmd_rcvrs;
+
+	/*
+	 * Events that were queues because no one was there to receive
+	 * them.
+	 */
+	spinlock_t       events_lock; /* For dealing with event stuff. */
+	struct list_head waiting_events;
+	unsigned int     waiting_events_count; /* How many events in queue? */
+	char             delivering_events;
+	char             event_msg_printed;
+	atomic_t         event_waiters;
+	unsigned int     ticks_to_req_ev;
+	int              last_needs_timer;
+
+	/*
+	 * The event receiver for my BMC, only really used at panic
+	 * shutdown as a place to store this.
+	 */
+	unsigned char event_receiver;
+	unsigned char event_receiver_lun;
+	unsigned char local_sel_device;
+	unsigned char local_event_generator;
+
+	/* For handling of maintenance mode. */
+	int maintenance_mode;
+	bool maintenance_mode_enable;
+	int auto_maintenance_timeout;
+	spinlock_t maintenance_mode_lock; /* Used in a timer... */
+
+	/*
+	 * If we are doing maintenance on something on IPMB, extend
+	 * the timeout time to avoid timeouts writing firmware and
+	 * such.
+	 */
+	int ipmb_maintenance_mode_timeout;
+
+	/*
+	 * 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
+	 * caller.  This only works on the system interface.
+	 *
+	 * Protected by bmc_reg_mutex.
+	 */
+	void (*null_user_handler)(struct ipmi_smi *intf,
+				  struct ipmi_recv_msg *msg);
+
+	/*
+	 * When we are scanning the channels for an SMI, this will
+	 * tell which channel we are scanning.
+	 */
+	int curr_channel;
+
+	/* Channel information */
+	struct ipmi_channel_set *channel_list;
+	unsigned int curr_working_cset; /* First index into the following. */
+	struct ipmi_channel_set wchannels[2];
+	struct ipmi_my_addrinfo addrinfo[IPMI_MAX_CHANNELS];
+	bool channels_ready;
+
+	atomic_t stats[IPMI_NUM_STATS];
+
+	/*
+	 * run_to_completion duplicate of smb_info, smi_info
+	 * and ipmi_serial_info structures. Used to decrease numbers of
+	 * parameters passed by "low" level IPMI code.
+	 */
+	int run_to_completion;
+};
+#define to_si_intf_from_dev(device) container_of(device, struct ipmi_smi, dev)
+
+static void __get_guid(struct ipmi_smi *intf);
+static void __ipmi_bmc_unregister(struct ipmi_smi *intf);
+static int __ipmi_bmc_register(struct ipmi_smi *intf,
+			       struct ipmi_device_id *id,
+			       bool guid_set, guid_t *guid, int intf_num);
+static int __scan_channels(struct ipmi_smi *intf, struct ipmi_device_id *id);
+
+
+/**
+ * The driver model view of the IPMI messaging driver.
+ */
+static struct platform_driver ipmidriver = {
+	.driver = {
+		.name = "ipmi",
+		.bus = &platform_bus_type
+	}
+};
+/*
+ * This mutex keeps us from adding the same BMC twice.
+ */
+static DEFINE_MUTEX(ipmidriver_mutex);
+
+static LIST_HEAD(ipmi_interfaces);
+static DEFINE_MUTEX(ipmi_interfaces_mutex);
+struct srcu_struct ipmi_interfaces_srcu;
+
+/*
+ * List of watchers that want to know when smi's are added and deleted.
+ */
+static LIST_HEAD(smi_watchers);
+static DEFINE_MUTEX(smi_watchers_mutex);
+
+#define ipmi_inc_stat(intf, stat) \
+	atomic_inc(&(intf)->stats[IPMI_STAT_ ## stat])
+#define ipmi_get_stat(intf, stat) \
+	((unsigned int) atomic_read(&(intf)->stats[IPMI_STAT_ ## stat]))
+
+static const char * const addr_src_to_str[] = {
+	"invalid", "hotmod", "hardcoded", "SPMI", "ACPI", "SMBIOS", "PCI",
+	"device-tree", "platform"
+};
+
+const char *ipmi_addr_src_to_str(enum ipmi_addr_src src)
+{
+	if (src >= SI_LAST)
+		src = 0; /* Invalid */
+	return addr_src_to_str[src];
+}
+EXPORT_SYMBOL(ipmi_addr_src_to_str);
+
+static int is_lan_addr(struct ipmi_addr *addr)
+{
+	return addr->addr_type == IPMI_LAN_ADDR_TYPE;
+}
+
+static int is_ipmb_addr(struct ipmi_addr *addr)
+{
+	return addr->addr_type == IPMI_IPMB_ADDR_TYPE;
+}
+
+static int is_ipmb_bcast_addr(struct ipmi_addr *addr)
+{
+	return addr->addr_type == IPMI_IPMB_BROADCAST_ADDR_TYPE;
+}
+
+static void free_recv_msg_list(struct list_head *q)
+{
+	struct ipmi_recv_msg *msg, *msg2;
+
+	list_for_each_entry_safe(msg, msg2, q, link) {
+		list_del(&msg->link);
+		ipmi_free_recv_msg(msg);
+	}
+}
+
+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(struct ipmi_smi *intf)
+{
+	int              i;
+	struct cmd_rcvr  *rcvr, *rcvr2;
+	struct list_head list;
+
+	tasklet_kill(&intf->recv_tasklet);
+
+	free_smi_msg_list(&intf->waiting_rcv_msgs);
+	free_recv_msg_list(&intf->waiting_events);
+
+	/*
+	 * Wholesale remove all the entries from the list in the
+	 * interface and wait for RCU to know that none are in use.
+	 */
+	mutex_lock(&intf->cmd_rcvrs_mutex);
+	INIT_LIST_HEAD(&list);
+	list_splice_init_rcu(&intf->cmd_rcvrs, &list, synchronize_rcu);
+	mutex_unlock(&intf->cmd_rcvrs_mutex);
+
+	list_for_each_entry_safe(rcvr, rcvr2, &list, link)
+		kfree(rcvr);
+
+	for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) {
+		if ((intf->seq_table[i].inuse)
+					&& (intf->seq_table[i].recv_msg))
+			ipmi_free_recv_msg(intf->seq_table[i].recv_msg);
+	}
+}
+
+static void intf_free(struct kref *ref)
+{
+	struct ipmi_smi *intf = container_of(ref, struct ipmi_smi, refcount);
+
+	clean_up_interface_data(intf);
+	kfree(intf);
+}
+
+struct watcher_entry {
+	int              intf_num;
+	struct ipmi_smi  *intf;
+	struct list_head link;
+};
+
+int ipmi_smi_watcher_register(struct ipmi_smi_watcher *watcher)
+{
+	struct ipmi_smi *intf;
+	int index, rv;
+
+	/*
+	 * Make sure the driver is actually initialized, this handles
+	 * problems with initialization order.
+	 */
+	rv = ipmi_init_msghandler();
+	if (rv)
+		return rv;
+
+	mutex_lock(&smi_watchers_mutex);
+
+	list_add(&watcher->link, &smi_watchers);
+
+	index = srcu_read_lock(&ipmi_interfaces_srcu);
+	list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
+		int intf_num = READ_ONCE(intf->intf_num);
+
+		if (intf_num == -1)
+			continue;
+		watcher->new_smi(intf_num, intf->si_dev);
+	}
+	srcu_read_unlock(&ipmi_interfaces_srcu, index);
+
+	mutex_unlock(&smi_watchers_mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL(ipmi_smi_watcher_register);
+
+int ipmi_smi_watcher_unregister(struct ipmi_smi_watcher *watcher)
+{
+	mutex_lock(&smi_watchers_mutex);
+	list_del(&watcher->link);
+	mutex_unlock(&smi_watchers_mutex);
+	return 0;
+}
+EXPORT_SYMBOL(ipmi_smi_watcher_unregister);
+
+/*
+ * Must be called with smi_watchers_mutex held.
+ */
+static void
+call_smi_watchers(int i, struct device *dev)
+{
+	struct ipmi_smi_watcher *w;
+
+	mutex_lock(&smi_watchers_mutex);
+	list_for_each_entry(w, &smi_watchers, link) {
+		if (try_module_get(w->owner)) {
+			w->new_smi(i, dev);
+			module_put(w->owner);
+		}
+	}
+	mutex_unlock(&smi_watchers_mutex);
+}
+
+static int
+ipmi_addr_equal(struct ipmi_addr *addr1, struct ipmi_addr *addr2)
+{
+	if (addr1->addr_type != addr2->addr_type)
+		return 0;
+
+	if (addr1->channel != addr2->channel)
+		return 0;
+
+	if (addr1->addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE) {
+		struct ipmi_system_interface_addr *smi_addr1
+		    = (struct ipmi_system_interface_addr *) addr1;
+		struct ipmi_system_interface_addr *smi_addr2
+		    = (struct ipmi_system_interface_addr *) addr2;
+		return (smi_addr1->lun == smi_addr2->lun);
+	}
+
+	if (is_ipmb_addr(addr1) || is_ipmb_bcast_addr(addr1)) {
+		struct ipmi_ipmb_addr *ipmb_addr1
+		    = (struct ipmi_ipmb_addr *) addr1;
+		struct ipmi_ipmb_addr *ipmb_addr2
+		    = (struct ipmi_ipmb_addr *) addr2;
+
+		return ((ipmb_addr1->slave_addr == ipmb_addr2->slave_addr)
+			&& (ipmb_addr1->lun == ipmb_addr2->lun));
+	}
+
+	if (is_lan_addr(addr1)) {
+		struct ipmi_lan_addr *lan_addr1
+			= (struct ipmi_lan_addr *) addr1;
+		struct ipmi_lan_addr *lan_addr2
+		    = (struct ipmi_lan_addr *) addr2;
+
+		return ((lan_addr1->remote_SWID == lan_addr2->remote_SWID)
+			&& (lan_addr1->local_SWID == lan_addr2->local_SWID)
+			&& (lan_addr1->session_handle
+			    == lan_addr2->session_handle)
+			&& (lan_addr1->lun == lan_addr2->lun));
+	}
+
+	return 1;
+}
+
+int ipmi_validate_addr(struct ipmi_addr *addr, int len)
+{
+	if (len < sizeof(struct ipmi_system_interface_addr))
+		return -EINVAL;
+
+	if (addr->addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE) {
+		if (addr->channel != IPMI_BMC_CHANNEL)
+			return -EINVAL;
+		return 0;
+	}
+
+	if ((addr->channel == IPMI_BMC_CHANNEL)
+	    || (addr->channel >= IPMI_MAX_CHANNELS)
+	    || (addr->channel < 0))
+		return -EINVAL;
+
+	if (is_ipmb_addr(addr) || is_ipmb_bcast_addr(addr)) {
+		if (len < sizeof(struct ipmi_ipmb_addr))
+			return -EINVAL;
+		return 0;
+	}
+
+	if (is_lan_addr(addr)) {
+		if (len < sizeof(struct ipmi_lan_addr))
+			return -EINVAL;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+EXPORT_SYMBOL(ipmi_validate_addr);
+
+unsigned int ipmi_addr_length(int addr_type)
+{
+	if (addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
+		return sizeof(struct ipmi_system_interface_addr);
+
+	if ((addr_type == IPMI_IPMB_ADDR_TYPE)
+			|| (addr_type == IPMI_IPMB_BROADCAST_ADDR_TYPE))
+		return sizeof(struct ipmi_ipmb_addr);
+
+	if (addr_type == IPMI_LAN_ADDR_TYPE)
+		return sizeof(struct ipmi_lan_addr);
+
+	return 0;
+}
+EXPORT_SYMBOL(ipmi_addr_length);
+
+static int deliver_response(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
+{
+	int rv = 0;
+
+	if (!msg->user) {
+		/* Special handling for NULL users. */
+		if (intf->null_user_handler) {
+			intf->null_user_handler(intf, msg);
+		} else {
+			/* No handler, so give up. */
+			rv = -EINVAL;
+		}
+		ipmi_free_recv_msg(msg);
+	} else if (!oops_in_progress) {
+		/*
+		 * If we are running in the panic context, calling the
+		 * receive handler doesn't much meaning and has a deadlock
+		 * risk.  At this moment, simply skip it in that case.
+		 */
+		int index;
+		struct ipmi_user *user = acquire_ipmi_user(msg->user, &index);
+
+		if (user) {
+			user->handler->ipmi_recv_hndl(msg, user->handler_data);
+			release_ipmi_user(user, index);
+		} else {
+			/* User went away, give up. */
+			ipmi_free_recv_msg(msg);
+			rv = -EINVAL;
+		}
+	}
+
+	return rv;
+}
+
+static void deliver_local_response(struct ipmi_smi *intf,
+				   struct ipmi_recv_msg *msg)
+{
+	if (deliver_response(intf, msg))
+		ipmi_inc_stat(intf, unhandled_local_responses);
+	else
+		ipmi_inc_stat(intf, handled_local_responses);
+}
+
+static void deliver_err_response(struct ipmi_smi *intf,
+				 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_local_response(intf, 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.
+ */
+static int intf_next_seq(struct ipmi_smi      *intf,
+			 struct ipmi_recv_msg *recv_msg,
+			 unsigned long        timeout,
+			 int                  retries,
+			 int                  broadcast,
+			 unsigned char        *seq,
+			 long                 *seqid)
+{
+	int          rv = 0;
+	unsigned int i;
+
+	if (timeout == 0)
+		timeout = default_retry_ms;
+	if (retries < 0)
+		retries = default_max_retries;
+
+	for (i = intf->curr_seq; (i+1)%IPMI_IPMB_NUM_SEQ != intf->curr_seq;
+					i = (i+1)%IPMI_IPMB_NUM_SEQ) {
+		if (!intf->seq_table[i].inuse)
+			break;
+	}
+
+	if (!intf->seq_table[i].inuse) {
+		intf->seq_table[i].recv_msg = recv_msg;
+
+		/*
+		 * Start with the maximum timeout, when the send response
+		 * comes in we will start the real timer.
+		 */
+		intf->seq_table[i].timeout = MAX_MSG_TIMEOUT;
+		intf->seq_table[i].orig_timeout = timeout;
+		intf->seq_table[i].retries_left = retries;
+		intf->seq_table[i].broadcast = broadcast;
+		intf->seq_table[i].inuse = 1;
+		intf->seq_table[i].seqid = NEXT_SEQID(intf->seq_table[i].seqid);
+		*seq = i;
+		*seqid = intf->seq_table[i].seqid;
+		intf->curr_seq = (i+1)%IPMI_IPMB_NUM_SEQ;
+		need_waiter(intf);
+	} else {
+		rv = -EAGAIN;
+	}
+
+	return rv;
+}
+
+/*
+ * Return the receive message for the given sequence number and
+ * release the sequence number so it can be reused.  Some other data
+ * is passed in to be sure the message matches up correctly (to help
+ * guard against message coming in after their timeout and the
+ * sequence number being reused).
+ */
+static int intf_find_seq(struct ipmi_smi      *intf,
+			 unsigned char        seq,
+			 short                channel,
+			 unsigned char        cmd,
+			 unsigned char        netfn,
+			 struct ipmi_addr     *addr,
+			 struct ipmi_recv_msg **recv_msg)
+{
+	int           rv = -ENODEV;
+	unsigned long flags;
+
+	if (seq >= IPMI_IPMB_NUM_SEQ)
+		return -EINVAL;
+
+	spin_lock_irqsave(&intf->seq_lock, flags);
+	if (intf->seq_table[seq].inuse) {
+		struct ipmi_recv_msg *msg = intf->seq_table[seq].recv_msg;
+
+		if ((msg->addr.channel == channel) && (msg->msg.cmd == cmd)
+				&& (msg->msg.netfn == netfn)
+				&& (ipmi_addr_equal(addr, &msg->addr))) {
+			*recv_msg = msg;
+			intf->seq_table[seq].inuse = 0;
+			rv = 0;
+		}
+	}
+	spin_unlock_irqrestore(&intf->seq_lock, flags);
+
+	return rv;
+}
+
+
+/* Start the timer for a specific sequence table entry. */
+static int intf_start_seq_timer(struct ipmi_smi *intf,
+				long       msgid)
+{
+	int           rv = -ENODEV;
+	unsigned long flags;
+	unsigned char seq;
+	unsigned long seqid;
+
+
+	GET_SEQ_FROM_MSGID(msgid, seq, seqid);
+
+	spin_lock_irqsave(&intf->seq_lock, flags);
+	/*
+	 * We do this verification because the user can be deleted
+	 * while a message is outstanding.
+	 */
+	if ((intf->seq_table[seq].inuse)
+				&& (intf->seq_table[seq].seqid == seqid)) {
+		struct seq_table *ent = &intf->seq_table[seq];
+		ent->timeout = ent->orig_timeout;
+		rv = 0;
+	}
+	spin_unlock_irqrestore(&intf->seq_lock, flags);
+
+	return rv;
+}
+
+/* Got an error for the send message for a specific sequence number. */
+static int intf_err_seq(struct ipmi_smi *intf,
+			long         msgid,
+			unsigned int err)
+{
+	int                  rv = -ENODEV;
+	unsigned long        flags;
+	unsigned char        seq;
+	unsigned long        seqid;
+	struct ipmi_recv_msg *msg = NULL;
+
+
+	GET_SEQ_FROM_MSGID(msgid, seq, seqid);
+
+	spin_lock_irqsave(&intf->seq_lock, flags);
+	/*
+	 * We do this verification because the user can be deleted
+	 * while a message is outstanding.
+	 */
+	if ((intf->seq_table[seq].inuse)
+				&& (intf->seq_table[seq].seqid == seqid)) {
+		struct seq_table *ent = &intf->seq_table[seq];
+
+		ent->inuse = 0;
+		msg = ent->recv_msg;
+		rv = 0;
+	}
+	spin_unlock_irqrestore(&intf->seq_lock, flags);
+
+	if (msg)
+		deliver_err_response(intf, msg, err);
+
+	return rv;
+}
+
+
+static void free_user_work(struct work_struct *work)
+{
+	struct ipmi_user *user = container_of(work, struct ipmi_user,
+					      remove_work);
+
+	cleanup_srcu_struct(&user->release_barrier);
+	vfree(user);
+}
+
+int ipmi_create_user(unsigned int          if_num,
+		     const struct ipmi_user_hndl *handler,
+		     void                  *handler_data,
+		     struct ipmi_user      **user)
+{
+	unsigned long flags;
+	struct ipmi_user *new_user;
+	int           rv, index;
+	struct ipmi_smi *intf;
+
+	/*
+	 * There is no module usecount here, because it's not
+	 * required.  Since this can only be used by and called from
+	 * other modules, they will implicitly use this module, and
+	 * thus this can't be removed unless the other modules are
+	 * removed.
+	 */
+
+	if (handler == NULL)
+		return -EINVAL;
+
+	/*
+	 * Make sure the driver is actually initialized, this handles
+	 * problems with initialization order.
+	 */
+	rv = ipmi_init_msghandler();
+	if (rv)
+		return rv;
+
+	new_user = vzalloc(sizeof(*new_user));
+	if (!new_user)
+		return -ENOMEM;
+
+	index = srcu_read_lock(&ipmi_interfaces_srcu);
+	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:
+	INIT_WORK(&new_user->remove_work, free_user_work);
+
+	rv = init_srcu_struct(&new_user->release_barrier);
+	if (rv)
+		goto out_kfree;
+
+	if (!try_module_get(intf->owner)) {
+		rv = -ENODEV;
+		goto out_kfree;
+	}
+
+	/* Note that each existing user holds a refcount to the interface. */
+	kref_get(&intf->refcount);
+
+	kref_init(&new_user->refcount);
+	new_user->handler = handler;
+	new_user->handler_data = handler_data;
+	new_user->intf = intf;
+	new_user->gets_events = false;
+
+	rcu_assign_pointer(new_user->self, new_user);
+	spin_lock_irqsave(&intf->seq_lock, flags);
+	list_add_rcu(&new_user->link, &intf->users);
+	spin_unlock_irqrestore(&intf->seq_lock, flags);
+	if (handler->ipmi_watchdog_pretimeout) {
+		/* User wants pretimeouts, so make sure to watch for them. */
+		if (atomic_inc_return(&intf->event_waiters) == 1)
+			need_waiter(intf);
+	}
+	srcu_read_unlock(&ipmi_interfaces_srcu, index);
+	*user = new_user;
+	return 0;
+
+out_kfree:
+	srcu_read_unlock(&ipmi_interfaces_srcu, index);
+	vfree(new_user);
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_create_user);
+
+int ipmi_get_smi_info(int if_num, struct ipmi_smi_info *data)
+{
+	int rv, index;
+	struct ipmi_smi *intf;
+
+	index = srcu_read_lock(&ipmi_interfaces_srcu);
+	list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
+		if (intf->intf_num == if_num)
+			goto found;
+	}
+	srcu_read_unlock(&ipmi_interfaces_srcu, index);
+
+	/* Not found, return an error */
+	return -EINVAL;
+
+found:
+	if (!intf->handlers->get_smi_info)
+		rv = -ENOTTY;
+	else
+		rv = intf->handlers->get_smi_info(intf->send_info, data);
+	srcu_read_unlock(&ipmi_interfaces_srcu, index);
+
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_get_smi_info);
+
+static void free_user(struct kref *ref)
+{
+	struct ipmi_user *user = container_of(ref, struct ipmi_user, refcount);
+
+	/* SRCU cleanup must happen in task context. */
+	queue_work(remove_work_wq, &user->remove_work);
+}
+
+static void _ipmi_destroy_user(struct ipmi_user *user)
+{
+	struct ipmi_smi  *intf = user->intf;
+	int              i;
+	unsigned long    flags;
+	struct cmd_rcvr  *rcvr;
+	struct cmd_rcvr  *rcvrs = NULL;
+
+	if (!acquire_ipmi_user(user, &i)) {
+		/*
+		 * The user has already been cleaned up, just make sure
+		 * nothing is using it and return.
+		 */
+		synchronize_srcu(&user->release_barrier);
+		return;
+	}
+
+	rcu_assign_pointer(user->self, NULL);
+	release_ipmi_user(user, i);
+
+	synchronize_srcu(&user->release_barrier);
+
+	if (user->handler->shutdown)
+		user->handler->shutdown(user->handler_data);
+
+	if (user->handler->ipmi_watchdog_pretimeout)
+		atomic_dec(&intf->event_waiters);
+
+	if (user->gets_events)
+		atomic_dec(&intf->event_waiters);
+
+	/* Remove the user from the interface's sequence table. */
+	spin_lock_irqsave(&intf->seq_lock, flags);
+	list_del_rcu(&user->link);
+
+	for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) {
+		if (intf->seq_table[i].inuse
+		    && (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);
+
+	/*
+	 * Remove the user from the command receiver's table.  First
+	 * we build a list of everything (not using the standard link,
+	 * since other things may be using it till we do
+	 * synchronize_srcu()) then free everything in that list.
+	 */
+	mutex_lock(&intf->cmd_rcvrs_mutex);
+	list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link) {
+		if (rcvr->user == user) {
+			list_del_rcu(&rcvr->link);
+			rcvr->next = rcvrs;
+			rcvrs = rcvr;
+		}
+	}
+	mutex_unlock(&intf->cmd_rcvrs_mutex);
+	synchronize_rcu();
+	while (rcvrs) {
+		rcvr = rcvrs;
+		rcvrs = rcvr->next;
+		kfree(rcvr);
+	}
+
+	kref_put(&intf->refcount, intf_free);
+	module_put(intf->owner);
+}
+
+int ipmi_destroy_user(struct ipmi_user *user)
+{
+	_ipmi_destroy_user(user);
+
+	kref_put(&user->refcount, free_user);
+
+	return 0;
+}
+EXPORT_SYMBOL(ipmi_destroy_user);
+
+int ipmi_get_version(struct ipmi_user *user,
+		     unsigned char *major,
+		     unsigned char *minor)
+{
+	struct ipmi_device_id id;
+	int rv, index;
+
+	user = acquire_ipmi_user(user, &index);
+	if (!user)
+		return -ENODEV;
+
+	rv = bmc_get_device_id(user->intf, NULL, &id, NULL, NULL);
+	if (!rv) {
+		*major = ipmi_version_major(&id);
+		*minor = ipmi_version_minor(&id);
+	}
+	release_ipmi_user(user, index);
+
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_get_version);
+
+int ipmi_set_my_address(struct ipmi_user *user,
+			unsigned int  channel,
+			unsigned char address)
+{
+	int index, rv = 0;
+
+	user = acquire_ipmi_user(user, &index);
+	if (!user)
+		return -ENODEV;
+
+	if (channel >= IPMI_MAX_CHANNELS) {
+		rv = -EINVAL;
+	} else {
+		channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
+		user->intf->addrinfo[channel].address = address;
+	}
+	release_ipmi_user(user, index);
+
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_set_my_address);
+
+int ipmi_get_my_address(struct ipmi_user *user,
+			unsigned int  channel,
+			unsigned char *address)
+{
+	int index, rv = 0;
+
+	user = acquire_ipmi_user(user, &index);
+	if (!user)
+		return -ENODEV;
+
+	if (channel >= IPMI_MAX_CHANNELS) {
+		rv = -EINVAL;
+	} else {
+		channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
+		*address = user->intf->addrinfo[channel].address;
+	}
+	release_ipmi_user(user, index);
+
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_get_my_address);
+
+int ipmi_set_my_LUN(struct ipmi_user *user,
+		    unsigned int  channel,
+		    unsigned char LUN)
+{
+	int index, rv = 0;
+
+	user = acquire_ipmi_user(user, &index);
+	if (!user)
+		return -ENODEV;
+
+	if (channel >= IPMI_MAX_CHANNELS) {
+		rv = -EINVAL;
+	} else {
+		channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
+		user->intf->addrinfo[channel].lun = LUN & 0x3;
+	}
+	release_ipmi_user(user, index);
+
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_set_my_LUN);
+
+int ipmi_get_my_LUN(struct ipmi_user *user,
+		    unsigned int  channel,
+		    unsigned char *address)
+{
+	int index, rv = 0;
+
+	user = acquire_ipmi_user(user, &index);
+	if (!user)
+		return -ENODEV;
+
+	if (channel >= IPMI_MAX_CHANNELS) {
+		rv = -EINVAL;
+	} else {
+		channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
+		*address = user->intf->addrinfo[channel].lun;
+	}
+	release_ipmi_user(user, index);
+
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_get_my_LUN);
+
+int ipmi_get_maintenance_mode(struct ipmi_user *user)
+{
+	int mode, index;
+	unsigned long flags;
+
+	user = acquire_ipmi_user(user, &index);
+	if (!user)
+		return -ENODEV;
+
+	spin_lock_irqsave(&user->intf->maintenance_mode_lock, flags);
+	mode = user->intf->maintenance_mode;
+	spin_unlock_irqrestore(&user->intf->maintenance_mode_lock, flags);
+	release_ipmi_user(user, index);
+
+	return mode;
+}
+EXPORT_SYMBOL(ipmi_get_maintenance_mode);
+
+static void maintenance_mode_update(struct ipmi_smi *intf)
+{
+	if (intf->handlers->set_maintenance_mode)
+		intf->handlers->set_maintenance_mode(
+			intf->send_info, intf->maintenance_mode_enable);
+}
+
+int ipmi_set_maintenance_mode(struct ipmi_user *user, int mode)
+{
+	int rv = 0, index;
+	unsigned long flags;
+	struct ipmi_smi *intf = user->intf;
+
+	user = acquire_ipmi_user(user, &index);
+	if (!user)
+		return -ENODEV;
+
+	spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
+	if (intf->maintenance_mode != mode) {
+		switch (mode) {
+		case IPMI_MAINTENANCE_MODE_AUTO:
+			intf->maintenance_mode_enable
+				= (intf->auto_maintenance_timeout > 0);
+			break;
+
+		case IPMI_MAINTENANCE_MODE_OFF:
+			intf->maintenance_mode_enable = false;
+			break;
+
+		case IPMI_MAINTENANCE_MODE_ON:
+			intf->maintenance_mode_enable = true;
+			break;
+
+		default:
+			rv = -EINVAL;
+			goto out_unlock;
+		}
+		intf->maintenance_mode = mode;
+
+		maintenance_mode_update(intf);
+	}
+ out_unlock:
+	spin_unlock_irqrestore(&intf->maintenance_mode_lock, flags);
+	release_ipmi_user(user, index);
+
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_set_maintenance_mode);
+
+int ipmi_set_gets_events(struct ipmi_user *user, bool val)
+{
+	unsigned long        flags;
+	struct ipmi_smi      *intf = user->intf;
+	struct ipmi_recv_msg *msg, *msg2;
+	struct list_head     msgs;
+	int index;
+
+	user = acquire_ipmi_user(user, &index);
+	if (!user)
+		return -ENODEV;
+
+	INIT_LIST_HEAD(&msgs);
+
+	spin_lock_irqsave(&intf->events_lock, flags);
+	if (user->gets_events == val)
+		goto out;
+
+	user->gets_events = val;
+
+	if (val) {
+		if (atomic_inc_return(&intf->event_waiters) == 1)
+			need_waiter(intf);
+	} else {
+		atomic_dec(&intf->event_waiters);
+	}
+
+	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;
+		if (intf->event_msg_printed) {
+			dev_warn(intf->si_dev,
+				 PFX "Event queue no longer full\n");
+			intf->event_msg_printed = 0;
+		}
+
+		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_local_response(intf, msg);
+		}
+
+		spin_lock_irqsave(&intf->events_lock, flags);
+		intf->delivering_events = 0;
+	}
+
+ out:
+	spin_unlock_irqrestore(&intf->events_lock, flags);
+	release_ipmi_user(user, index);
+
+	return 0;
+}
+EXPORT_SYMBOL(ipmi_set_gets_events);
+
+static struct cmd_rcvr *find_cmd_rcvr(struct ipmi_smi *intf,
+				      unsigned char netfn,
+				      unsigned char cmd,
+				      unsigned char chan)
+{
+	struct cmd_rcvr *rcvr;
+
+	list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link) {
+		if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd)
+					&& (rcvr->chans & (1 << chan)))
+			return rcvr;
+	}
+	return NULL;
+}
+
+static int is_cmd_rcvr_exclusive(struct ipmi_smi *intf,
+				 unsigned char netfn,
+				 unsigned char cmd,
+				 unsigned int  chans)
+{
+	struct cmd_rcvr *rcvr;
+
+	list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link) {
+		if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd)
+					&& (rcvr->chans & chans))
+			return 0;
+	}
+	return 1;
+}
+
+int ipmi_register_for_cmd(struct ipmi_user *user,
+			  unsigned char netfn,
+			  unsigned char cmd,
+			  unsigned int  chans)
+{
+	struct ipmi_smi *intf = user->intf;
+	struct cmd_rcvr *rcvr;
+	int rv = 0, index;
+
+	user = acquire_ipmi_user(user, &index);
+	if (!user)
+		return -ENODEV;
+
+	rcvr = kmalloc(sizeof(*rcvr), GFP_KERNEL);
+	if (!rcvr) {
+		rv = -ENOMEM;
+		goto out_release;
+	}
+	rcvr->cmd = cmd;
+	rcvr->netfn = netfn;
+	rcvr->chans = chans;
+	rcvr->user = user;
+
+	mutex_lock(&intf->cmd_rcvrs_mutex);
+	/* Make sure the command/netfn is not already registered. */
+	if (!is_cmd_rcvr_exclusive(intf, netfn, cmd, chans)) {
+		rv = -EBUSY;
+		goto out_unlock;
+	}
+
+	if (atomic_inc_return(&intf->event_waiters) == 1)
+		need_waiter(intf);
+
+	list_add_rcu(&rcvr->link, &intf->cmd_rcvrs);
+
+out_unlock:
+	mutex_unlock(&intf->cmd_rcvrs_mutex);
+	if (rv)
+		kfree(rcvr);
+out_release:
+	release_ipmi_user(user, index);
+
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_register_for_cmd);
+
+int ipmi_unregister_for_cmd(struct ipmi_user *user,
+			    unsigned char netfn,
+			    unsigned char cmd,
+			    unsigned int  chans)
+{
+	struct ipmi_smi *intf = user->intf;
+	struct cmd_rcvr *rcvr;
+	struct cmd_rcvr *rcvrs = NULL;
+	int i, rv = -ENOENT, index;
+
+	user = acquire_ipmi_user(user, &index);
+	if (!user)
+		return -ENODEV;
+
+	mutex_lock(&intf->cmd_rcvrs_mutex);
+	for (i = 0; i < IPMI_NUM_CHANNELS; i++) {
+		if (((1 << i) & chans) == 0)
+			continue;
+		rcvr = find_cmd_rcvr(intf, netfn, cmd, i);
+		if (rcvr == NULL)
+			continue;
+		if (rcvr->user == user) {
+			rv = 0;
+			rcvr->chans &= ~chans;
+			if (rcvr->chans == 0) {
+				list_del_rcu(&rcvr->link);
+				rcvr->next = rcvrs;
+				rcvrs = rcvr;
+			}
+		}
+	}
+	mutex_unlock(&intf->cmd_rcvrs_mutex);
+	synchronize_rcu();
+	release_ipmi_user(user, index);
+	while (rcvrs) {
+		atomic_dec(&intf->event_waiters);
+		rcvr = rcvrs;
+		rcvrs = rcvr->next;
+		kfree(rcvr);
+	}
+
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_unregister_for_cmd);
+
+static unsigned char
+ipmb_checksum(unsigned char *data, int size)
+{
+	unsigned char csum = 0;
+
+	for (; size > 0; size--, data++)
+		csum += *data;
+
+	return -csum;
+}
+
+static inline void format_ipmb_msg(struct ipmi_smi_msg   *smi_msg,
+				   struct kernel_ipmi_msg *msg,
+				   struct ipmi_ipmb_addr *ipmb_addr,
+				   long                  msgid,
+				   unsigned char         ipmb_seq,
+				   int                   broadcast,
+				   unsigned char         source_address,
+				   unsigned char         source_lun)
+{
+	int i = broadcast;
+
+	/* Format the IPMB header data. */
+	smi_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
+	smi_msg->data[1] = IPMI_SEND_MSG_CMD;
+	smi_msg->data[2] = ipmb_addr->channel;
+	if (broadcast)
+		smi_msg->data[3] = 0;
+	smi_msg->data[i+3] = ipmb_addr->slave_addr;
+	smi_msg->data[i+4] = (msg->netfn << 2) | (ipmb_addr->lun & 0x3);
+	smi_msg->data[i+5] = ipmb_checksum(&smi_msg->data[i + 3], 2);
+	smi_msg->data[i+6] = source_address;
+	smi_msg->data[i+7] = (ipmb_seq << 2) | source_lun;
+	smi_msg->data[i+8] = msg->cmd;
+
+	/* Now tack on the data to the message. */
+	if (msg->data_len > 0)
+		memcpy(&smi_msg->data[i + 9], msg->data, msg->data_len);
+	smi_msg->data_size = msg->data_len + 9;
+
+	/* Now calculate the checksum and tack it on. */
+	smi_msg->data[i+smi_msg->data_size]
+		= ipmb_checksum(&smi_msg->data[i + 6], smi_msg->data_size - 6);
+
+	/*
+	 * Add on the checksum size and the offset from the
+	 * broadcast.
+	 */
+	smi_msg->data_size += 1 + i;
+
+	smi_msg->msgid = msgid;
+}
+
+static inline void format_lan_msg(struct ipmi_smi_msg   *smi_msg,
+				  struct kernel_ipmi_msg *msg,
+				  struct ipmi_lan_addr  *lan_addr,
+				  long                  msgid,
+				  unsigned char         ipmb_seq,
+				  unsigned char         source_lun)
+{
+	/* Format the IPMB header data. */
+	smi_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
+	smi_msg->data[1] = IPMI_SEND_MSG_CMD;
+	smi_msg->data[2] = lan_addr->channel;
+	smi_msg->data[3] = lan_addr->session_handle;
+	smi_msg->data[4] = lan_addr->remote_SWID;
+	smi_msg->data[5] = (msg->netfn << 2) | (lan_addr->lun & 0x3);
+	smi_msg->data[6] = ipmb_checksum(&smi_msg->data[4], 2);
+	smi_msg->data[7] = lan_addr->local_SWID;
+	smi_msg->data[8] = (ipmb_seq << 2) | source_lun;
+	smi_msg->data[9] = msg->cmd;
+
+	/* Now tack on the data to the message. */
+	if (msg->data_len > 0)
+		memcpy(&smi_msg->data[10], msg->data, msg->data_len);
+	smi_msg->data_size = msg->data_len + 10;
+
+	/* Now calculate the checksum and tack it on. */
+	smi_msg->data[smi_msg->data_size]
+		= ipmb_checksum(&smi_msg->data[7], smi_msg->data_size - 7);
+
+	/*
+	 * Add on the checksum size and the offset from the
+	 * broadcast.
+	 */
+	smi_msg->data_size += 1;
+
+	smi_msg->msgid = msgid;
+}
+
+static struct ipmi_smi_msg *smi_add_send_msg(struct ipmi_smi *intf,
+					     struct ipmi_smi_msg *smi_msg,
+					     int priority)
+{
+	if (intf->curr_msg) {
+		if (priority > 0)
+			list_add_tail(&smi_msg->link, &intf->hp_xmit_msgs);
+		else
+			list_add_tail(&smi_msg->link, &intf->xmit_msgs);
+		smi_msg = NULL;
+	} else {
+		intf->curr_msg = smi_msg;
+	}
+
+	return smi_msg;
+}
+
+
+static void smi_send(struct ipmi_smi *intf,
+		     const struct ipmi_smi_handlers *handlers,
+		     struct ipmi_smi_msg *smi_msg, int priority)
+{
+	int run_to_completion = intf->run_to_completion;
+
+	if (run_to_completion) {
+		smi_msg = smi_add_send_msg(intf, smi_msg, priority);
+	} else {
+		unsigned long flags;
+
+		spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
+		smi_msg = smi_add_send_msg(intf, smi_msg, priority);
+		spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
+	}
+
+	if (smi_msg)
+		handlers->sender(intf->send_info, smi_msg);
+}
+
+static bool is_maintenance_mode_cmd(struct kernel_ipmi_msg *msg)
+{
+	return (((msg->netfn == IPMI_NETFN_APP_REQUEST)
+		 && ((msg->cmd == IPMI_COLD_RESET_CMD)
+		     || (msg->cmd == IPMI_WARM_RESET_CMD)))
+		|| (msg->netfn == IPMI_NETFN_FIRMWARE_REQUEST));
+}
+
+static int i_ipmi_req_sysintf(struct ipmi_smi        *intf,
+			      struct ipmi_addr       *addr,
+			      long                   msgid,
+			      struct kernel_ipmi_msg *msg,
+			      struct ipmi_smi_msg    *smi_msg,
+			      struct ipmi_recv_msg   *recv_msg,
+			      int                    retries,
+			      unsigned int           retry_time_ms)
+{
+	struct ipmi_system_interface_addr *smi_addr;
+
+	if (msg->netfn & 1)
+		/* Responses are not allowed to the SMI. */
+		return -EINVAL;
+
+	smi_addr = (struct ipmi_system_interface_addr *) addr;
+	if (smi_addr->lun > 3) {
+		ipmi_inc_stat(intf, sent_invalid_commands);
+		return -EINVAL;
+	}
+
+	memcpy(&recv_msg->addr, smi_addr, sizeof(*smi_addr));
+
+	if ((msg->netfn == IPMI_NETFN_APP_REQUEST)
+	    && ((msg->cmd == IPMI_SEND_MSG_CMD)
+		|| (msg->cmd == IPMI_GET_MSG_CMD)
+		|| (msg->cmd == IPMI_READ_EVENT_MSG_BUFFER_CMD))) {
+		/*
+		 * We don't let the user do these, since we manage
+		 * the sequence numbers.
+		 */
+		ipmi_inc_stat(intf, sent_invalid_commands);
+		return -EINVAL;
+	}
+
+	if (is_maintenance_mode_cmd(msg)) {
+		unsigned long flags;
+
+		spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
+		intf->auto_maintenance_timeout
+			= maintenance_mode_timeout_ms;
+		if (!intf->maintenance_mode
+		    && !intf->maintenance_mode_enable) {
+			intf->maintenance_mode_enable = true;
+			maintenance_mode_update(intf);
+		}
+		spin_unlock_irqrestore(&intf->maintenance_mode_lock,
+				       flags);
+	}
+
+	if (msg->data_len + 2 > IPMI_MAX_MSG_LENGTH) {
+		ipmi_inc_stat(intf, sent_invalid_commands);
+		return -EMSGSIZE;
+	}
+
+	smi_msg->data[0] = (msg->netfn << 2) | (smi_addr->lun & 0x3);
+	smi_msg->data[1] = msg->cmd;
+	smi_msg->msgid = msgid;
+	smi_msg->user_data = recv_msg;
+	if (msg->data_len > 0)
+		memcpy(&smi_msg->data[2], msg->data, msg->data_len);
+	smi_msg->data_size = msg->data_len + 2;
+	ipmi_inc_stat(intf, sent_local_commands);
+
+	return 0;
+}
+
+static int i_ipmi_req_ipmb(struct ipmi_smi        *intf,
+			   struct ipmi_addr       *addr,
+			   long                   msgid,
+			   struct kernel_ipmi_msg *msg,
+			   struct ipmi_smi_msg    *smi_msg,
+			   struct ipmi_recv_msg   *recv_msg,
+			   unsigned char          source_address,
+			   unsigned char          source_lun,
+			   int                    retries,
+			   unsigned int           retry_time_ms)
+{
+	struct ipmi_ipmb_addr *ipmb_addr;
+	unsigned char ipmb_seq;
+	long seqid;
+	int broadcast = 0;
+	struct ipmi_channel *chans;
+	int rv = 0;
+
+	if (addr->channel >= IPMI_MAX_CHANNELS) {
+		ipmi_inc_stat(intf, sent_invalid_commands);
+		return -EINVAL;
+	}
+
+	chans = READ_ONCE(intf->channel_list)->c;
+
+	if (chans[addr->channel].medium != IPMI_CHANNEL_MEDIUM_IPMB) {
+		ipmi_inc_stat(intf, sent_invalid_commands);
+		return -EINVAL;
+	}
+
+	if (addr->addr_type == IPMI_IPMB_BROADCAST_ADDR_TYPE) {
+		/*
+		 * Broadcasts add a zero at the beginning of the
+		 * message, but otherwise is the same as an IPMB
+		 * address.
+		 */
+		addr->addr_type = IPMI_IPMB_ADDR_TYPE;
+		broadcast = 1;
+		retries = 0; /* Don't retry broadcasts. */
+	}
+
+	/*
+	 * 9 for the header and 1 for the checksum, plus
+	 * possibly one for the broadcast.
+	 */
+	if ((msg->data_len + 10 + broadcast) > IPMI_MAX_MSG_LENGTH) {
+		ipmi_inc_stat(intf, sent_invalid_commands);
+		return -EMSGSIZE;
+	}
+
+	ipmb_addr = (struct ipmi_ipmb_addr *) addr;
+	if (ipmb_addr->lun > 3) {
+		ipmi_inc_stat(intf, sent_invalid_commands);
+		return -EINVAL;
+	}
+
+	memcpy(&recv_msg->addr, ipmb_addr, sizeof(*ipmb_addr));
+
+	if (recv_msg->msg.netfn & 0x1) {
+		/*
+		 * It's a response, so use the user's sequence
+		 * from msgid.
+		 */
+		ipmi_inc_stat(intf, sent_ipmb_responses);
+		format_ipmb_msg(smi_msg, msg, ipmb_addr, msgid,
+				msgid, broadcast,
+				source_address, source_lun);
+
+		/*
+		 * Save the receive message so we can use it
+		 * to deliver the response.
+		 */
+		smi_msg->user_data = recv_msg;
+	} else {
+		/* It's a command, so get a sequence for it. */
+		unsigned long flags;
+
+		spin_lock_irqsave(&intf->seq_lock, flags);
+
+		if (is_maintenance_mode_cmd(msg))
+			intf->ipmb_maintenance_mode_timeout =
+				maintenance_mode_timeout_ms;
+
+		if (intf->ipmb_maintenance_mode_timeout && retry_time_ms == 0)
+			/* Different default in maintenance mode */
+			retry_time_ms = default_maintenance_retry_ms;
+
+		/*
+		 * Create a sequence number with a 1 second
+		 * timeout and 4 retries.
+		 */
+		rv = intf_next_seq(intf,
+				   recv_msg,
+				   retry_time_ms,
+				   retries,
+				   broadcast,
+				   &ipmb_seq,
+				   &seqid);
+		if (rv)
+			/*
+			 * We have used up all the sequence numbers,
+			 * probably, so abort.
+			 */
+			goto out_err;
+
+		ipmi_inc_stat(intf, sent_ipmb_commands);
+
+		/*
+		 * Store the sequence number in the message,
+		 * so that when the send message response
+		 * comes back we can start the timer.
+		 */
+		format_ipmb_msg(smi_msg, msg, ipmb_addr,
+				STORE_SEQ_IN_MSGID(ipmb_seq, seqid),
+				ipmb_seq, broadcast,
+				source_address, source_lun);
+
+		/*
+		 * Copy the message into the recv message data, so we
+		 * can retransmit it later if necessary.
+		 */
+		memcpy(recv_msg->msg_data, smi_msg->data,
+		       smi_msg->data_size);
+		recv_msg->msg.data = recv_msg->msg_data;
+		recv_msg->msg.data_len = smi_msg->data_size;
+
+		/*
+		 * We don't unlock until here, because we need
+		 * to copy the completed message into the
+		 * recv_msg before we release the lock.
+		 * Otherwise, race conditions may bite us.  I
+		 * know that's pretty paranoid, but I prefer
+		 * to be correct.
+		 */
+out_err:
+		spin_unlock_irqrestore(&intf->seq_lock, flags);
+	}
+
+	return rv;
+}
+
+static int i_ipmi_req_lan(struct ipmi_smi        *intf,
+			  struct ipmi_addr       *addr,
+			  long                   msgid,
+			  struct kernel_ipmi_msg *msg,
+			  struct ipmi_smi_msg    *smi_msg,
+			  struct ipmi_recv_msg   *recv_msg,
+			  unsigned char          source_lun,
+			  int                    retries,
+			  unsigned int           retry_time_ms)
+{
+	struct ipmi_lan_addr  *lan_addr;
+	unsigned char ipmb_seq;
+	long seqid;
+	struct ipmi_channel *chans;
+	int rv = 0;
+
+	if (addr->channel >= IPMI_MAX_CHANNELS) {
+		ipmi_inc_stat(intf, sent_invalid_commands);
+		return -EINVAL;
+	}
+
+	chans = READ_ONCE(intf->channel_list)->c;
+
+	if ((chans[addr->channel].medium
+				!= IPMI_CHANNEL_MEDIUM_8023LAN)
+			&& (chans[addr->channel].medium
+			    != IPMI_CHANNEL_MEDIUM_ASYNC)) {
+		ipmi_inc_stat(intf, sent_invalid_commands);
+		return -EINVAL;
+	}
+
+	/* 11 for the header and 1 for the checksum. */
+	if ((msg->data_len + 12) > IPMI_MAX_MSG_LENGTH) {
+		ipmi_inc_stat(intf, sent_invalid_commands);
+		return -EMSGSIZE;
+	}
+
+	lan_addr = (struct ipmi_lan_addr *) addr;
+	if (lan_addr->lun > 3) {
+		ipmi_inc_stat(intf, sent_invalid_commands);
+		return -EINVAL;
+	}
+
+	memcpy(&recv_msg->addr, lan_addr, sizeof(*lan_addr));
+
+	if (recv_msg->msg.netfn & 0x1) {
+		/*
+		 * It's a response, so use the user's sequence
+		 * from msgid.
+		 */
+		ipmi_inc_stat(intf, sent_lan_responses);
+		format_lan_msg(smi_msg, msg, lan_addr, msgid,
+			       msgid, source_lun);
+
+		/*
+		 * Save the receive message so we can use it
+		 * to deliver the response.
+		 */
+		smi_msg->user_data = recv_msg;
+	} else {
+		/* It's a command, so get a sequence for it. */
+		unsigned long flags;
+
+		spin_lock_irqsave(&intf->seq_lock, flags);
+
+		/*
+		 * Create a sequence number with a 1 second
+		 * timeout and 4 retries.
+		 */
+		rv = intf_next_seq(intf,
+				   recv_msg,
+				   retry_time_ms,
+				   retries,
+				   0,
+				   &ipmb_seq,
+				   &seqid);
+		if (rv)
+			/*
+			 * We have used up all the sequence numbers,
+			 * probably, so abort.
+			 */
+			goto out_err;
+
+		ipmi_inc_stat(intf, sent_lan_commands);
+
+		/*
+		 * Store the sequence number in the message,
+		 * so that when the send message response
+		 * comes back we can start the timer.
+		 */
+		format_lan_msg(smi_msg, msg, lan_addr,
+			       STORE_SEQ_IN_MSGID(ipmb_seq, seqid),
+			       ipmb_seq, source_lun);
+
+		/*
+		 * Copy the message into the recv message data, so we
+		 * can retransmit it later if necessary.
+		 */
+		memcpy(recv_msg->msg_data, smi_msg->data,
+		       smi_msg->data_size);
+		recv_msg->msg.data = recv_msg->msg_data;
+		recv_msg->msg.data_len = smi_msg->data_size;
+
+		/*
+		 * We don't unlock until here, because we need
+		 * to copy the completed message into the
+		 * recv_msg before we release the lock.
+		 * Otherwise, race conditions may bite us.  I
+		 * know that's pretty paranoid, but I prefer
+		 * to be correct.
+		 */
+out_err:
+		spin_unlock_irqrestore(&intf->seq_lock, flags);
+	}
+
+	return rv;
+}
+
+/*
+ * Separate from ipmi_request so that the user does not have to be
+ * supplied in certain circumstances (mainly at panic time).  If
+ * messages are supplied, they will be freed, even if an error
+ * occurs.
+ */
+static int i_ipmi_request(struct ipmi_user     *user,
+			  struct ipmi_smi      *intf,
+			  struct ipmi_addr     *addr,
+			  long                 msgid,
+			  struct kernel_ipmi_msg *msg,
+			  void                 *user_msg_data,
+			  void                 *supplied_smi,
+			  struct ipmi_recv_msg *supplied_recv,
+			  int                  priority,
+			  unsigned char        source_address,
+			  unsigned char        source_lun,
+			  int                  retries,
+			  unsigned int         retry_time_ms)
+{
+	struct ipmi_smi_msg *smi_msg;
+	struct ipmi_recv_msg *recv_msg;
+	int rv = 0;
+
+	if (supplied_recv)
+		recv_msg = supplied_recv;
+	else {
+		recv_msg = ipmi_alloc_recv_msg();
+		if (recv_msg == NULL) {
+			rv = -ENOMEM;
+			goto out;
+		}
+	}
+	recv_msg->user_msg_data = user_msg_data;
+
+	if (supplied_smi)
+		smi_msg = (struct ipmi_smi_msg *) supplied_smi;
+	else {
+		smi_msg = ipmi_alloc_smi_msg();
+		if (smi_msg == NULL) {
+			ipmi_free_recv_msg(recv_msg);
+			rv = -ENOMEM;
+			goto out;
+		}
+	}
+
+	rcu_read_lock();
+	if (intf->in_shutdown) {
+		rv = -ENODEV;
+		goto out_err;
+	}
+
+	recv_msg->user = user;
+	if (user)
+		/* The put happens when the message is freed. */
+		kref_get(&user->refcount);
+	recv_msg->msgid = msgid;
+	/*
+	 * Store the message to send in the receive message so timeout
+	 * responses can get the proper response data.
+	 */
+	recv_msg->msg = *msg;
+
+	if (addr->addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE) {
+		rv = i_ipmi_req_sysintf(intf, addr, msgid, msg, smi_msg,
+					recv_msg, retries, retry_time_ms);
+	} else if (is_ipmb_addr(addr) || is_ipmb_bcast_addr(addr)) {
+		rv = i_ipmi_req_ipmb(intf, addr, msgid, msg, smi_msg, recv_msg,
+				     source_address, source_lun,
+				     retries, retry_time_ms);
+	} else if (is_lan_addr(addr)) {
+		rv = i_ipmi_req_lan(intf, addr, msgid, msg, smi_msg, recv_msg,
+				    source_lun, retries, retry_time_ms);
+	} else {
+	    /* Unknown address type. */
+		ipmi_inc_stat(intf, sent_invalid_commands);
+		rv = -EINVAL;
+	}
+
+	if (rv) {
+out_err:
+		ipmi_free_smi_msg(smi_msg);
+		ipmi_free_recv_msg(recv_msg);
+	} else {
+		ipmi_debug_msg("Send", smi_msg->data, smi_msg->data_size);
+
+		smi_send(intf, intf->handlers, smi_msg, priority);
+	}
+	rcu_read_unlock();
+
+out:
+	return rv;
+}
+
+static int check_addr(struct ipmi_smi  *intf,
+		      struct ipmi_addr *addr,
+		      unsigned char    *saddr,
+		      unsigned char    *lun)
+{
+	if (addr->channel >= IPMI_MAX_CHANNELS)
+		return -EINVAL;
+	addr->channel = array_index_nospec(addr->channel, IPMI_MAX_CHANNELS);
+	*lun = intf->addrinfo[addr->channel].lun;
+	*saddr = intf->addrinfo[addr->channel].address;
+	return 0;
+}
+
+int ipmi_request_settime(struct ipmi_user *user,
+			 struct ipmi_addr *addr,
+			 long             msgid,
+			 struct kernel_ipmi_msg  *msg,
+			 void             *user_msg_data,
+			 int              priority,
+			 int              retries,
+			 unsigned int     retry_time_ms)
+{
+	unsigned char saddr = 0, lun = 0;
+	int rv, index;
+
+	if (!user)
+		return -EINVAL;
+
+	user = acquire_ipmi_user(user, &index);
+	if (!user)
+		return -ENODEV;
+
+	rv = check_addr(user->intf, addr, &saddr, &lun);
+	if (!rv)
+		rv = i_ipmi_request(user,
+				    user->intf,
+				    addr,
+				    msgid,
+				    msg,
+				    user_msg_data,
+				    NULL, NULL,
+				    priority,
+				    saddr,
+				    lun,
+				    retries,
+				    retry_time_ms);
+
+	release_ipmi_user(user, index);
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_request_settime);
+
+int ipmi_request_supply_msgs(struct ipmi_user     *user,
+			     struct ipmi_addr     *addr,
+			     long                 msgid,
+			     struct kernel_ipmi_msg *msg,
+			     void                 *user_msg_data,
+			     void                 *supplied_smi,
+			     struct ipmi_recv_msg *supplied_recv,
+			     int                  priority)
+{
+	unsigned char saddr = 0, lun = 0;
+	int rv, index;
+
+	if (!user)
+		return -EINVAL;
+
+	user = acquire_ipmi_user(user, &index);
+	if (!user)
+		return -ENODEV;
+
+	rv = check_addr(user->intf, addr, &saddr, &lun);
+	if (!rv)
+		rv = i_ipmi_request(user,
+				    user->intf,
+				    addr,
+				    msgid,
+				    msg,
+				    user_msg_data,
+				    supplied_smi,
+				    supplied_recv,
+				    priority,
+				    saddr,
+				    lun,
+				    -1, 0);
+
+	release_ipmi_user(user, index);
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_request_supply_msgs);
+
+static void bmc_device_id_handler(struct ipmi_smi *intf,
+				  struct ipmi_recv_msg *msg)
+{
+	int rv;
+
+	if ((msg->addr.addr_type != IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
+			|| (msg->msg.netfn != IPMI_NETFN_APP_RESPONSE)
+			|| (msg->msg.cmd != IPMI_GET_DEVICE_ID_CMD)) {
+		dev_warn(intf->si_dev,
+			 PFX "invalid device_id msg: addr_type=%d netfn=%x cmd=%x\n",
+			msg->addr.addr_type, msg->msg.netfn, msg->msg.cmd);
+		return;
+	}
+
+	rv = ipmi_demangle_device_id(msg->msg.netfn, msg->msg.cmd,
+			msg->msg.data, msg->msg.data_len, &intf->bmc->fetch_id);
+	if (rv) {
+		dev_warn(intf->si_dev,
+			 PFX "device id demangle failed: %d\n", rv);
+		intf->bmc->dyn_id_set = 0;
+	} else {
+		/*
+		 * Make sure the id data is available before setting
+		 * dyn_id_set.
+		 */
+		smp_wmb();
+		intf->bmc->dyn_id_set = 1;
+	}
+
+	wake_up(&intf->waitq);
+}
+
+static int
+send_get_device_id_cmd(struct ipmi_smi *intf)
+{
+	struct ipmi_system_interface_addr si;
+	struct kernel_ipmi_msg msg;
+
+	si.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
+	si.channel = IPMI_BMC_CHANNEL;
+	si.lun = 0;
+
+	msg.netfn = IPMI_NETFN_APP_REQUEST;
+	msg.cmd = IPMI_GET_DEVICE_ID_CMD;
+	msg.data = NULL;
+	msg.data_len = 0;
+
+	return i_ipmi_request(NULL,
+			      intf,
+			      (struct ipmi_addr *) &si,
+			      0,
+			      &msg,
+			      intf,
+			      NULL,
+			      NULL,
+			      0,
+			      intf->addrinfo[0].address,
+			      intf->addrinfo[0].lun,
+			      -1, 0);
+}
+
+static int __get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc)
+{
+	int rv;
+
+	bmc->dyn_id_set = 2;
+
+	intf->null_user_handler = bmc_device_id_handler;
+
+	rv = send_get_device_id_cmd(intf);
+	if (rv)
+		return rv;
+
+	wait_event(intf->waitq, bmc->dyn_id_set != 2);
+
+	if (!bmc->dyn_id_set)
+		rv = -EIO; /* Something went wrong in the fetch. */
+
+	/* dyn_id_set makes the id data available. */
+	smp_rmb();
+
+	intf->null_user_handler = NULL;
+
+	return rv;
+}
+
+/*
+ * Fetch the device id for the bmc/interface.  You must pass in either
+ * bmc or intf, this code will get the other one.  If the data has
+ * been recently fetched, this will just use the cached data.  Otherwise
+ * it will run a new fetch.
+ *
+ * Except for the first time this is called (in ipmi_add_smi()),
+ * this will always return good data;
+ */
+static int __bmc_get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc,
+			       struct ipmi_device_id *id,
+			       bool *guid_set, guid_t *guid, int intf_num)
+{
+	int rv = 0;
+	int prev_dyn_id_set, prev_guid_set;
+	bool intf_set = intf != NULL;
+
+	if (!intf) {
+		mutex_lock(&bmc->dyn_mutex);
+retry_bmc_lock:
+		if (list_empty(&bmc->intfs)) {
+			mutex_unlock(&bmc->dyn_mutex);
+			return -ENOENT;
+		}
+		intf = list_first_entry(&bmc->intfs, struct ipmi_smi,
+					bmc_link);
+		kref_get(&intf->refcount);
+		mutex_unlock(&bmc->dyn_mutex);
+		mutex_lock(&intf->bmc_reg_mutex);
+		mutex_lock(&bmc->dyn_mutex);
+		if (intf != list_first_entry(&bmc->intfs, struct ipmi_smi,
+					     bmc_link)) {
+			mutex_unlock(&intf->bmc_reg_mutex);
+			kref_put(&intf->refcount, intf_free);
+			goto retry_bmc_lock;
+		}
+	} else {
+		mutex_lock(&intf->bmc_reg_mutex);
+		bmc = intf->bmc;
+		mutex_lock(&bmc->dyn_mutex);
+		kref_get(&intf->refcount);
+	}
+
+	/* If we have a valid and current ID, just return that. */
+	if (intf->in_bmc_register ||
+	    (bmc->dyn_id_set && time_is_after_jiffies(bmc->dyn_id_expiry)))
+		goto out_noprocessing;
+
+	prev_guid_set = bmc->dyn_guid_set;
+	__get_guid(intf);
+
+	prev_dyn_id_set = bmc->dyn_id_set;
+	rv = __get_device_id(intf, bmc);
+	if (rv)
+		goto out;
+
+	/*
+	 * The guid, device id, manufacturer id, and product id should
+	 * not change on a BMC.  If it does we have to do some dancing.
+	 */
+	if (!intf->bmc_registered
+	    || (!prev_guid_set && bmc->dyn_guid_set)
+	    || (!prev_dyn_id_set && bmc->dyn_id_set)
+	    || (prev_guid_set && bmc->dyn_guid_set
+		&& !guid_equal(&bmc->guid, &bmc->fetch_guid))
+	    || bmc->id.device_id != bmc->fetch_id.device_id
+	    || bmc->id.manufacturer_id != bmc->fetch_id.manufacturer_id
+	    || bmc->id.product_id != bmc->fetch_id.product_id) {
+		struct ipmi_device_id id = bmc->fetch_id;
+		int guid_set = bmc->dyn_guid_set;
+		guid_t guid;
+
+		guid = bmc->fetch_guid;
+		mutex_unlock(&bmc->dyn_mutex);
+
+		__ipmi_bmc_unregister(intf);
+		/* Fill in the temporary BMC for good measure. */
+		intf->bmc->id = id;
+		intf->bmc->dyn_guid_set = guid_set;
+		intf->bmc->guid = guid;
+		if (__ipmi_bmc_register(intf, &id, guid_set, &guid, intf_num))
+			need_waiter(intf); /* Retry later on an error. */
+		else
+			__scan_channels(intf, &id);
+
+
+		if (!intf_set) {
+			/*
+			 * We weren't given the interface on the
+			 * command line, so restart the operation on
+			 * the next interface for the BMC.
+			 */
+			mutex_unlock(&intf->bmc_reg_mutex);
+			mutex_lock(&bmc->dyn_mutex);
+			goto retry_bmc_lock;
+		}
+
+		/* We have a new BMC, set it up. */
+		bmc = intf->bmc;
+		mutex_lock(&bmc->dyn_mutex);
+		goto out_noprocessing;
+	} else if (memcmp(&bmc->fetch_id, &bmc->id, sizeof(bmc->id)))
+		/* Version info changes, scan the channels again. */
+		__scan_channels(intf, &bmc->fetch_id);
+
+	bmc->dyn_id_expiry = jiffies + IPMI_DYN_DEV_ID_EXPIRY;
+
+out:
+	if (rv && prev_dyn_id_set) {
+		rv = 0; /* Ignore failures if we have previous data. */
+		bmc->dyn_id_set = prev_dyn_id_set;
+	}
+	if (!rv) {
+		bmc->id = bmc->fetch_id;
+		if (bmc->dyn_guid_set)
+			bmc->guid = bmc->fetch_guid;
+		else if (prev_guid_set)
+			/*
+			 * The guid used to be valid and it failed to fetch,
+			 * just use the cached value.
+			 */
+			bmc->dyn_guid_set = prev_guid_set;
+	}
+out_noprocessing:
+	if (!rv) {
+		if (id)
+			*id = bmc->id;
+
+		if (guid_set)
+			*guid_set = bmc->dyn_guid_set;
+
+		if (guid && bmc->dyn_guid_set)
+			*guid =  bmc->guid;
+	}
+
+	mutex_unlock(&bmc->dyn_mutex);
+	mutex_unlock(&intf->bmc_reg_mutex);
+
+	kref_put(&intf->refcount, intf_free);
+	return rv;
+}
+
+static int bmc_get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc,
+			     struct ipmi_device_id *id,
+			     bool *guid_set, guid_t *guid)
+{
+	return __bmc_get_device_id(intf, bmc, id, guid_set, guid, -1);
+}
+
+static ssize_t device_id_show(struct device *dev,
+			      struct device_attribute *attr,
+			      char *buf)
+{
+	struct bmc_device *bmc = to_bmc_device(dev);
+	struct ipmi_device_id id;
+	int rv;
+
+	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
+	if (rv)
+		return rv;
+
+	return snprintf(buf, 10, "%u\n", id.device_id);
+}
+static DEVICE_ATTR_RO(device_id);
+
+static ssize_t provides_device_sdrs_show(struct device *dev,
+					 struct device_attribute *attr,
+					 char *buf)
+{
+	struct bmc_device *bmc = to_bmc_device(dev);
+	struct ipmi_device_id id;
+	int rv;
+
+	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
+	if (rv)
+		return rv;
+
+	return snprintf(buf, 10, "%u\n", (id.device_revision & 0x80) >> 7);
+}
+static DEVICE_ATTR_RO(provides_device_sdrs);
+
+static ssize_t revision_show(struct device *dev, struct device_attribute *attr,
+			     char *buf)
+{
+	struct bmc_device *bmc = to_bmc_device(dev);
+	struct ipmi_device_id id;
+	int rv;
+
+	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
+	if (rv)
+		return rv;
+
+	return snprintf(buf, 20, "%u\n", id.device_revision & 0x0F);
+}
+static DEVICE_ATTR_RO(revision);
+
+static ssize_t firmware_revision_show(struct device *dev,
+				      struct device_attribute *attr,
+				      char *buf)
+{
+	struct bmc_device *bmc = to_bmc_device(dev);
+	struct ipmi_device_id id;
+	int rv;
+
+	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
+	if (rv)
+		return rv;
+
+	return snprintf(buf, 20, "%u.%x\n", id.firmware_revision_1,
+			id.firmware_revision_2);
+}
+static DEVICE_ATTR_RO(firmware_revision);
+
+static ssize_t ipmi_version_show(struct device *dev,
+				 struct device_attribute *attr,
+				 char *buf)
+{
+	struct bmc_device *bmc = to_bmc_device(dev);
+	struct ipmi_device_id id;
+	int rv;
+
+	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
+	if (rv)
+		return rv;
+
+	return snprintf(buf, 20, "%u.%u\n",
+			ipmi_version_major(&id),
+			ipmi_version_minor(&id));
+}
+static DEVICE_ATTR_RO(ipmi_version);
+
+static ssize_t add_dev_support_show(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	struct bmc_device *bmc = to_bmc_device(dev);
+	struct ipmi_device_id id;
+	int rv;
+
+	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
+	if (rv)
+		return rv;
+
+	return snprintf(buf, 10, "0x%02x\n", id.additional_device_support);
+}
+static DEVICE_ATTR(additional_device_support, S_IRUGO, add_dev_support_show,
+		   NULL);
+
+static ssize_t manufacturer_id_show(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	struct bmc_device *bmc = to_bmc_device(dev);
+	struct ipmi_device_id id;
+	int rv;
+
+	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
+	if (rv)
+		return rv;
+
+	return snprintf(buf, 20, "0x%6.6x\n", id.manufacturer_id);
+}
+static DEVICE_ATTR_RO(manufacturer_id);
+
+static ssize_t product_id_show(struct device *dev,
+			       struct device_attribute *attr,
+			       char *buf)
+{
+	struct bmc_device *bmc = to_bmc_device(dev);
+	struct ipmi_device_id id;
+	int rv;
+
+	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
+	if (rv)
+		return rv;
+
+	return snprintf(buf, 10, "0x%4.4x\n", id.product_id);
+}
+static DEVICE_ATTR_RO(product_id);
+
+static ssize_t aux_firmware_rev_show(struct device *dev,
+				     struct device_attribute *attr,
+				     char *buf)
+{
+	struct bmc_device *bmc = to_bmc_device(dev);
+	struct ipmi_device_id id;
+	int rv;
+
+	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
+	if (rv)
+		return rv;
+
+	return snprintf(buf, 21, "0x%02x 0x%02x 0x%02x 0x%02x\n",
+			id.aux_firmware_revision[3],
+			id.aux_firmware_revision[2],
+			id.aux_firmware_revision[1],
+			id.aux_firmware_revision[0]);
+}
+static DEVICE_ATTR(aux_firmware_revision, S_IRUGO, aux_firmware_rev_show, NULL);
+
+static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct bmc_device *bmc = to_bmc_device(dev);
+	bool guid_set;
+	guid_t guid;
+	int rv;
+
+	rv = bmc_get_device_id(NULL, bmc, NULL, &guid_set, &guid);
+	if (rv)
+		return rv;
+	if (!guid_set)
+		return -ENOENT;
+
+	return snprintf(buf, 38, "%pUl\n", guid.b);
+}
+static DEVICE_ATTR_RO(guid);
+
+static struct attribute *bmc_dev_attrs[] = {
+	&dev_attr_device_id.attr,
+	&dev_attr_provides_device_sdrs.attr,
+	&dev_attr_revision.attr,
+	&dev_attr_firmware_revision.attr,
+	&dev_attr_ipmi_version.attr,
+	&dev_attr_additional_device_support.attr,
+	&dev_attr_manufacturer_id.attr,
+	&dev_attr_product_id.attr,
+	&dev_attr_aux_firmware_revision.attr,
+	&dev_attr_guid.attr,
+	NULL
+};
+
+static umode_t bmc_dev_attr_is_visible(struct kobject *kobj,
+				       struct attribute *attr, int idx)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct bmc_device *bmc = to_bmc_device(dev);
+	umode_t mode = attr->mode;
+	int rv;
+
+	if (attr == &dev_attr_aux_firmware_revision.attr) {
+		struct ipmi_device_id id;
+
+		rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
+		return (!rv && id.aux_firmware_revision_set) ? mode : 0;
+	}
+	if (attr == &dev_attr_guid.attr) {
+		bool guid_set;
+
+		rv = bmc_get_device_id(NULL, bmc, NULL, &guid_set, NULL);
+		return (!rv && guid_set) ? mode : 0;
+	}
+	return mode;
+}
+
+static const struct attribute_group bmc_dev_attr_group = {
+	.attrs		= bmc_dev_attrs,
+	.is_visible	= bmc_dev_attr_is_visible,
+};
+
+static const struct attribute_group *bmc_dev_attr_groups[] = {
+	&bmc_dev_attr_group,
+	NULL
+};
+
+static const struct device_type bmc_device_type = {
+	.groups		= bmc_dev_attr_groups,
+};
+
+static int __find_bmc_guid(struct device *dev, void *data)
+{
+	guid_t *guid = data;
+	struct bmc_device *bmc;
+	int rv;
+
+	if (dev->type != &bmc_device_type)
+		return 0;
+
+	bmc = to_bmc_device(dev);
+	rv = bmc->dyn_guid_set && guid_equal(&bmc->guid, guid);
+	if (rv)
+		rv = kref_get_unless_zero(&bmc->usecount);
+	return rv;
+}
+
+/*
+ * Returns with the bmc's usecount incremented, if it is non-NULL.
+ */
+static struct bmc_device *ipmi_find_bmc_guid(struct device_driver *drv,
+					     guid_t *guid)
+{
+	struct device *dev;
+	struct bmc_device *bmc = NULL;
+
+	dev = driver_find_device(drv, NULL, guid, __find_bmc_guid);
+	if (dev) {
+		bmc = to_bmc_device(dev);
+		put_device(dev);
+	}
+	return bmc;
+}
+
+struct prod_dev_id {
+	unsigned int  product_id;
+	unsigned char device_id;
+};
+
+static int __find_bmc_prod_dev_id(struct device *dev, void *data)
+{
+	struct prod_dev_id *cid = data;
+	struct bmc_device *bmc;
+	int rv;
+
+	if (dev->type != &bmc_device_type)
+		return 0;
+
+	bmc = to_bmc_device(dev);
+	rv = (bmc->id.product_id == cid->product_id
+	      && bmc->id.device_id == cid->device_id);
+	if (rv)
+		rv = kref_get_unless_zero(&bmc->usecount);
+	return rv;
+}
+
+/*
+ * Returns with the bmc's usecount incremented, if it is non-NULL.
+ */
+static struct bmc_device *ipmi_find_bmc_prod_dev_id(
+	struct device_driver *drv,
+	unsigned int product_id, unsigned char device_id)
+{
+	struct prod_dev_id id = {
+		.product_id = product_id,
+		.device_id = device_id,
+	};
+	struct device *dev;
+	struct bmc_device *bmc = NULL;
+
+	dev = driver_find_device(drv, NULL, &id, __find_bmc_prod_dev_id);
+	if (dev) {
+		bmc = to_bmc_device(dev);
+		put_device(dev);
+	}
+	return bmc;
+}
+
+static DEFINE_IDA(ipmi_bmc_ida);
+
+static void
+release_bmc_device(struct device *dev)
+{
+	kfree(to_bmc_device(dev));
+}
+
+static void cleanup_bmc_work(struct work_struct *work)
+{
+	struct bmc_device *bmc = container_of(work, struct bmc_device,
+					      remove_work);
+	int id = bmc->pdev.id; /* Unregister overwrites id */
+
+	platform_device_unregister(&bmc->pdev);
+	ida_simple_remove(&ipmi_bmc_ida, id);
+}
+
+static void
+cleanup_bmc_device(struct kref *ref)
+{
+	struct bmc_device *bmc = container_of(ref, struct bmc_device, usecount);
+
+	/*
+	 * Remove the platform device in a work queue to avoid issues
+	 * with removing the device attributes while reading a device
+	 * attribute.
+	 */
+	queue_work(remove_work_wq, &bmc->remove_work);
+}
+
+/*
+ * Must be called with intf->bmc_reg_mutex held.
+ */
+static void __ipmi_bmc_unregister(struct ipmi_smi *intf)
+{
+	struct bmc_device *bmc = intf->bmc;
+
+	if (!intf->bmc_registered)
+		return;
+
+	sysfs_remove_link(&intf->si_dev->kobj, "bmc");
+	sysfs_remove_link(&bmc->pdev.dev.kobj, intf->my_dev_name);
+	kfree(intf->my_dev_name);
+	intf->my_dev_name = NULL;
+
+	mutex_lock(&bmc->dyn_mutex);
+	list_del(&intf->bmc_link);
+	mutex_unlock(&bmc->dyn_mutex);
+	intf->bmc = &intf->tmp_bmc;
+	kref_put(&bmc->usecount, cleanup_bmc_device);
+	intf->bmc_registered = false;
+}
+
+static void ipmi_bmc_unregister(struct ipmi_smi *intf)
+{
+	mutex_lock(&intf->bmc_reg_mutex);
+	__ipmi_bmc_unregister(intf);
+	mutex_unlock(&intf->bmc_reg_mutex);
+}
+
+/*
+ * Must be called with intf->bmc_reg_mutex held.
+ */
+static int __ipmi_bmc_register(struct ipmi_smi *intf,
+			       struct ipmi_device_id *id,
+			       bool guid_set, guid_t *guid, int intf_num)
+{
+	int               rv;
+	struct bmc_device *bmc;
+	struct bmc_device *old_bmc;
+
+	/*
+	 * platform_device_register() can cause bmc_reg_mutex to
+	 * be claimed because of the is_visible functions of
+	 * the attributes.  Eliminate possible recursion and
+	 * release the lock.
+	 */
+	intf->in_bmc_register = true;
+	mutex_unlock(&intf->bmc_reg_mutex);
+
+	/*
+	 * Try to find if there is an bmc_device struct
+	 * representing the interfaced BMC already
+	 */
+	mutex_lock(&ipmidriver_mutex);
+	if (guid_set)
+		old_bmc = ipmi_find_bmc_guid(&ipmidriver.driver, guid);
+	else
+		old_bmc = ipmi_find_bmc_prod_dev_id(&ipmidriver.driver,
+						    id->product_id,
+						    id->device_id);
+
+	/*
+	 * If there is already an bmc_device, free the new one,
+	 * otherwise register the new BMC device
+	 */
+	if (old_bmc) {
+		bmc = old_bmc;
+		/*
+		 * Note: old_bmc already has usecount incremented by
+		 * the BMC find functions.
+		 */
+		intf->bmc = old_bmc;
+		mutex_lock(&bmc->dyn_mutex);
+		list_add_tail(&intf->bmc_link, &bmc->intfs);
+		mutex_unlock(&bmc->dyn_mutex);
+
+		dev_info(intf->si_dev,
+			 "ipmi: interfacing existing BMC (man_id: 0x%6.6x,"
+			 " prod_id: 0x%4.4x, dev_id: 0x%2.2x)\n",
+			 bmc->id.manufacturer_id,
+			 bmc->id.product_id,
+			 bmc->id.device_id);
+	} else {
+		bmc = kzalloc(sizeof(*bmc), GFP_KERNEL);
+		if (!bmc) {
+			rv = -ENOMEM;
+			goto out;
+		}
+		INIT_LIST_HEAD(&bmc->intfs);
+		mutex_init(&bmc->dyn_mutex);
+		INIT_WORK(&bmc->remove_work, cleanup_bmc_work);
+
+		bmc->id = *id;
+		bmc->dyn_id_set = 1;
+		bmc->dyn_guid_set = guid_set;
+		bmc->guid = *guid;
+		bmc->dyn_id_expiry = jiffies + IPMI_DYN_DEV_ID_EXPIRY;
+
+		bmc->pdev.name = "ipmi_bmc";
+
+		rv = ida_simple_get(&ipmi_bmc_ida, 0, 0, GFP_KERNEL);
+		if (rv < 0) {
+			kfree(bmc);
+			goto out;
+		}
+
+		bmc->pdev.dev.driver = &ipmidriver.driver;
+		bmc->pdev.id = rv;
+		bmc->pdev.dev.release = release_bmc_device;
+		bmc->pdev.dev.type = &bmc_device_type;
+		kref_init(&bmc->usecount);
+
+		intf->bmc = bmc;
+		mutex_lock(&bmc->dyn_mutex);
+		list_add_tail(&intf->bmc_link, &bmc->intfs);
+		mutex_unlock(&bmc->dyn_mutex);
+
+		rv = platform_device_register(&bmc->pdev);
+		if (rv) {
+			dev_err(intf->si_dev,
+				PFX " Unable to register bmc device: %d\n",
+				rv);
+			goto out_list_del;
+		}
+
+		dev_info(intf->si_dev,
+			 "Found new BMC (man_id: 0x%6.6x, prod_id: 0x%4.4x, dev_id: 0x%2.2x)\n",
+			 bmc->id.manufacturer_id,
+			 bmc->id.product_id,
+			 bmc->id.device_id);
+	}
+
+	/*
+	 * create symlink from system interface device to bmc device
+	 * and back.
+	 */
+	rv = sysfs_create_link(&intf->si_dev->kobj, &bmc->pdev.dev.kobj, "bmc");
+	if (rv) {
+		dev_err(intf->si_dev,
+			PFX "Unable to create bmc symlink: %d\n", rv);
+		goto out_put_bmc;
+	}
+
+	if (intf_num == -1)
+		intf_num = intf->intf_num;
+	intf->my_dev_name = kasprintf(GFP_KERNEL, "ipmi%d", intf_num);
+	if (!intf->my_dev_name) {
+		rv = -ENOMEM;
+		dev_err(intf->si_dev,
+			PFX "Unable to allocate link from BMC: %d\n", rv);
+		goto out_unlink1;
+	}
+
+	rv = sysfs_create_link(&bmc->pdev.dev.kobj, &intf->si_dev->kobj,
+			       intf->my_dev_name);
+	if (rv) {
+		kfree(intf->my_dev_name);
+		intf->my_dev_name = NULL;
+		dev_err(intf->si_dev,
+			PFX "Unable to create symlink to bmc: %d\n", rv);
+		goto out_free_my_dev_name;
+	}
+
+	intf->bmc_registered = true;
+
+out:
+	mutex_unlock(&ipmidriver_mutex);
+	mutex_lock(&intf->bmc_reg_mutex);
+	intf->in_bmc_register = false;
+	return rv;
+
+
+out_free_my_dev_name:
+	kfree(intf->my_dev_name);
+	intf->my_dev_name = NULL;
+
+out_unlink1:
+	sysfs_remove_link(&intf->si_dev->kobj, "bmc");
+
+out_put_bmc:
+	mutex_lock(&bmc->dyn_mutex);
+	list_del(&intf->bmc_link);
+	mutex_unlock(&bmc->dyn_mutex);
+	intf->bmc = &intf->tmp_bmc;
+	kref_put(&bmc->usecount, cleanup_bmc_device);
+	goto out;
+
+out_list_del:
+	mutex_lock(&bmc->dyn_mutex);
+	list_del(&intf->bmc_link);
+	mutex_unlock(&bmc->dyn_mutex);
+	intf->bmc = &intf->tmp_bmc;
+	put_device(&bmc->pdev.dev);
+	goto out;
+}
+
+static int
+send_guid_cmd(struct ipmi_smi *intf, int chan)
+{
+	struct kernel_ipmi_msg            msg;
+	struct ipmi_system_interface_addr si;
+
+	si.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
+	si.channel = IPMI_BMC_CHANNEL;
+	si.lun = 0;
+
+	msg.netfn = IPMI_NETFN_APP_REQUEST;
+	msg.cmd = IPMI_GET_DEVICE_GUID_CMD;
+	msg.data = NULL;
+	msg.data_len = 0;
+	return i_ipmi_request(NULL,
+			      intf,
+			      (struct ipmi_addr *) &si,
+			      0,
+			      &msg,
+			      intf,
+			      NULL,
+			      NULL,
+			      0,
+			      intf->addrinfo[0].address,
+			      intf->addrinfo[0].lun,
+			      -1, 0);
+}
+
+static void guid_handler(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
+{
+	struct bmc_device *bmc = intf->bmc;
+
+	if ((msg->addr.addr_type != IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
+	    || (msg->msg.netfn != IPMI_NETFN_APP_RESPONSE)
+	    || (msg->msg.cmd != IPMI_GET_DEVICE_GUID_CMD))
+		/* Not for me */
+		return;
+
+	if (msg->msg.data[0] != 0) {
+		/* Error from getting the GUID, the BMC doesn't have one. */
+		bmc->dyn_guid_set = 0;
+		goto out;
+	}
+
+	if (msg->msg.data_len < 17) {
+		bmc->dyn_guid_set = 0;
+		dev_warn(intf->si_dev,
+			 PFX "The GUID response from the BMC was too short, it was %d but should have been 17.  Assuming GUID is not available.\n",
+			 msg->msg.data_len);
+		goto out;
+	}
+
+	memcpy(bmc->fetch_guid.b, msg->msg.data + 1, 16);
+	/*
+	 * Make sure the guid data is available before setting
+	 * dyn_guid_set.
+	 */
+	smp_wmb();
+	bmc->dyn_guid_set = 1;
+ out:
+	wake_up(&intf->waitq);
+}
+
+static void __get_guid(struct ipmi_smi *intf)
+{
+	int rv;
+	struct bmc_device *bmc = intf->bmc;
+
+	bmc->dyn_guid_set = 2;
+	intf->null_user_handler = guid_handler;
+	rv = send_guid_cmd(intf, 0);
+	if (rv)
+		/* Send failed, no GUID available. */
+		bmc->dyn_guid_set = 0;
+	else
+		wait_event(intf->waitq, bmc->dyn_guid_set != 2);
+
+	/* dyn_guid_set makes the guid data available. */
+	smp_rmb();
+
+	intf->null_user_handler = NULL;
+}
+
+static int
+send_channel_info_cmd(struct ipmi_smi *intf, int chan)
+{
+	struct kernel_ipmi_msg            msg;
+	unsigned char                     data[1];
+	struct ipmi_system_interface_addr si;
+
+	si.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
+	si.channel = IPMI_BMC_CHANNEL;
+	si.lun = 0;
+
+	msg.netfn = IPMI_NETFN_APP_REQUEST;
+	msg.cmd = IPMI_GET_CHANNEL_INFO_CMD;
+	msg.data = data;
+	msg.data_len = 1;
+	data[0] = chan;
+	return i_ipmi_request(NULL,
+			      intf,
+			      (struct ipmi_addr *) &si,
+			      0,
+			      &msg,
+			      intf,
+			      NULL,
+			      NULL,
+			      0,
+			      intf->addrinfo[0].address,
+			      intf->addrinfo[0].lun,
+			      -1, 0);
+}
+
+static void
+channel_handler(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
+{
+	int rv = 0;
+	int ch;
+	unsigned int set = intf->curr_working_cset;
+	struct ipmi_channel *chans;
+
+	if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
+	    && (msg->msg.netfn == IPMI_NETFN_APP_RESPONSE)
+	    && (msg->msg.cmd == IPMI_GET_CHANNEL_INFO_CMD)) {
+		/* It's the one we want */
+		if (msg->msg.data[0] != 0) {
+			/* Got an error from the channel, just go on. */
+
+			if (msg->msg.data[0] == IPMI_INVALID_COMMAND_ERR) {
+				/*
+				 * If the MC does not support this
+				 * command, that is legal.  We just
+				 * assume it has one IPMB at channel
+				 * zero.
+				 */
+				intf->wchannels[set].c[0].medium
+					= IPMI_CHANNEL_MEDIUM_IPMB;
+				intf->wchannels[set].c[0].protocol
+					= IPMI_CHANNEL_PROTOCOL_IPMB;
+
+				intf->channel_list = intf->wchannels + set;
+				intf->channels_ready = true;
+				wake_up(&intf->waitq);
+				goto out;
+			}
+			goto next_channel;
+		}
+		if (msg->msg.data_len < 4) {
+			/* Message not big enough, just go on. */
+			goto next_channel;
+		}
+		ch = intf->curr_channel;
+		chans = intf->wchannels[set].c;
+		chans[ch].medium = msg->msg.data[2] & 0x7f;
+		chans[ch].protocol = msg->msg.data[3] & 0x1f;
+
+ next_channel:
+		intf->curr_channel++;
+		if (intf->curr_channel >= IPMI_MAX_CHANNELS) {
+			intf->channel_list = intf->wchannels + set;
+			intf->channels_ready = true;
+			wake_up(&intf->waitq);
+		} else {
+			intf->channel_list = intf->wchannels + set;
+			intf->channels_ready = true;
+			rv = send_channel_info_cmd(intf, intf->curr_channel);
+		}
+
+		if (rv) {
+			/* Got an error somehow, just give up. */
+			dev_warn(intf->si_dev,
+				 PFX "Error sending channel information for channel %d: %d\n",
+				 intf->curr_channel, rv);
+
+			intf->channel_list = intf->wchannels + set;
+			intf->channels_ready = true;
+			wake_up(&intf->waitq);
+		}
+	}
+ out:
+	return;
+}
+
+/*
+ * Must be holding intf->bmc_reg_mutex to call this.
+ */
+static int __scan_channels(struct ipmi_smi *intf, struct ipmi_device_id *id)
+{
+	int rv;
+
+	if (ipmi_version_major(id) > 1
+			|| (ipmi_version_major(id) == 1
+			    && ipmi_version_minor(id) >= 5)) {
+		unsigned int set;
+
+		/*
+		 * Start scanning the channels to see what is
+		 * available.
+		 */
+		set = !intf->curr_working_cset;
+		intf->curr_working_cset = set;
+		memset(&intf->wchannels[set], 0,
+		       sizeof(struct ipmi_channel_set));
+
+		intf->null_user_handler = channel_handler;
+		intf->curr_channel = 0;
+		rv = send_channel_info_cmd(intf, 0);
+		if (rv) {
+			dev_warn(intf->si_dev,
+				 "Error sending channel information for channel 0, %d\n",
+				 rv);
+			return -EIO;
+		}
+
+		/* Wait for the channel info to be read. */
+		wait_event(intf->waitq, intf->channels_ready);
+		intf->null_user_handler = NULL;
+	} else {
+		unsigned int set = intf->curr_working_cset;
+
+		/* Assume a single IPMB channel at zero. */
+		intf->wchannels[set].c[0].medium = IPMI_CHANNEL_MEDIUM_IPMB;
+		intf->wchannels[set].c[0].protocol = IPMI_CHANNEL_PROTOCOL_IPMB;
+		intf->channel_list = intf->wchannels + set;
+		intf->channels_ready = true;
+	}
+
+	return 0;
+}
+
+static void ipmi_poll(struct ipmi_smi *intf)
+{
+	if (intf->handlers->poll)
+		intf->handlers->poll(intf->send_info);
+	/* In case something came in */
+	handle_new_recv_msgs(intf);
+}
+
+void ipmi_poll_interface(struct ipmi_user *user)
+{
+	ipmi_poll(user->intf);
+}
+EXPORT_SYMBOL(ipmi_poll_interface);
+
+static void redo_bmc_reg(struct work_struct *work)
+{
+	struct ipmi_smi *intf = container_of(work, struct ipmi_smi,
+					     bmc_reg_work);
+
+	if (!intf->in_shutdown)
+		bmc_get_device_id(intf, NULL, NULL, NULL, NULL);
+
+	kref_put(&intf->refcount, intf_free);
+}
+
+int ipmi_add_smi(struct module         *owner,
+		 const struct ipmi_smi_handlers *handlers,
+		 void		       *send_info,
+		 struct device         *si_dev,
+		 unsigned char         slave_addr)
+{
+	int              i, j;
+	int              rv;
+	struct ipmi_smi *intf, *tintf;
+	struct list_head *link;
+	struct ipmi_device_id id;
+
+	/*
+	 * Make sure the driver is actually initialized, this handles
+	 * problems with initialization order.
+	 */
+	rv = ipmi_init_msghandler();
+	if (rv)
+		return rv;
+
+	intf = kzalloc(sizeof(*intf), GFP_KERNEL);
+	if (!intf)
+		return -ENOMEM;
+
+	rv = init_srcu_struct(&intf->users_srcu);
+	if (rv) {
+		kfree(intf);
+		return rv;
+	}
+
+	intf->owner = owner;
+	intf->bmc = &intf->tmp_bmc;
+	INIT_LIST_HEAD(&intf->bmc->intfs);
+	mutex_init(&intf->bmc->dyn_mutex);
+	INIT_LIST_HEAD(&intf->bmc_link);
+	mutex_init(&intf->bmc_reg_mutex);
+	intf->intf_num = -1; /* Mark it invalid for now. */
+	kref_init(&intf->refcount);
+	INIT_WORK(&intf->bmc_reg_work, redo_bmc_reg);
+	intf->si_dev = si_dev;
+	for (j = 0; j < IPMI_MAX_CHANNELS; j++) {
+		intf->addrinfo[j].address = IPMI_BMC_SLAVE_ADDR;
+		intf->addrinfo[j].lun = 2;
+	}
+	if (slave_addr != 0)
+		intf->addrinfo[0].address = slave_addr;
+	INIT_LIST_HEAD(&intf->users);
+	intf->handlers = handlers;
+	intf->send_info = send_info;
+	spin_lock_init(&intf->seq_lock);
+	for (j = 0; j < IPMI_IPMB_NUM_SEQ; j++) {
+		intf->seq_table[j].inuse = 0;
+		intf->seq_table[j].seqid = 0;
+	}
+	intf->curr_seq = 0;
+	spin_lock_init(&intf->waiting_rcv_msgs_lock);
+	INIT_LIST_HEAD(&intf->waiting_rcv_msgs);
+	tasklet_init(&intf->recv_tasklet,
+		     smi_recv_tasklet,
+		     (unsigned long) intf);
+	atomic_set(&intf->watchdog_pretimeouts_to_deliver, 0);
+	spin_lock_init(&intf->xmit_msgs_lock);
+	INIT_LIST_HEAD(&intf->xmit_msgs);
+	INIT_LIST_HEAD(&intf->hp_xmit_msgs);
+	spin_lock_init(&intf->events_lock);
+	atomic_set(&intf->event_waiters, 0);
+	intf->ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
+	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);
+	for (i = 0; i < IPMI_NUM_STATS; i++)
+		atomic_set(&intf->stats[i], 0);
+
+	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++;
+	}
+	/* 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)
+		goto out_err;
+
+	rv = __bmc_get_device_id(intf, NULL, &id, NULL, NULL, i);
+	if (rv) {
+		dev_err(si_dev, "Unable to get the device id: %d\n", rv);
+		goto out_err_started;
+	}
+
+	mutex_lock(&intf->bmc_reg_mutex);
+	rv = __scan_channels(intf, &id);
+	mutex_unlock(&intf->bmc_reg_mutex);
+	if (rv)
+		goto out_err_bmc_reg;
+
+	/*
+	 * Keep memory order straight for RCU readers.  Make
+	 * sure everything else is committed to memory before
+	 * setting intf_num to mark the interface valid.
+	 */
+	smp_wmb();
+	intf->intf_num = i;
+	mutex_unlock(&ipmi_interfaces_mutex);
+
+	/* After this point the interface is legal to use. */
+	call_smi_watchers(i, intf->si_dev);
+
+	return 0;
+
+ out_err_bmc_reg:
+	ipmi_bmc_unregister(intf);
+ out_err_started:
+	if (intf->handlers->shutdown)
+		intf->handlers->shutdown(intf->send_info);
+ out_err:
+	list_del_rcu(&intf->link);
+	mutex_unlock(&ipmi_interfaces_mutex);
+	synchronize_srcu(&ipmi_interfaces_srcu);
+	cleanup_srcu_struct(&intf->users_srcu);
+	kref_put(&intf->refcount, intf_free);
+
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_add_smi);
+
+static void deliver_smi_err_response(struct ipmi_smi *intf,
+				     struct ipmi_smi_msg *msg,
+				     unsigned char err)
+{
+	msg->rsp[0] = msg->data[0] | 4;
+	msg->rsp[1] = msg->data[1];
+	msg->rsp[2] = err;
+	msg->rsp_size = 3;
+	/* It's an error, so it will never requeue, no need to check return. */
+	handle_one_recv_msg(intf, msg);
+}
+
+static void cleanup_smi_msgs(struct ipmi_smi *intf)
+{
+	int              i;
+	struct seq_table *ent;
+	struct ipmi_smi_msg *msg;
+	struct list_head *entry;
+	struct list_head tmplist;
+
+	/* Clear out our transmit queues and hold the messages. */
+	INIT_LIST_HEAD(&tmplist);
+	list_splice_tail(&intf->hp_xmit_msgs, &tmplist);
+	list_splice_tail(&intf->xmit_msgs, &tmplist);
+
+	/* Current message first, to preserve order */
+	while (intf->curr_msg && !list_empty(&intf->waiting_rcv_msgs)) {
+		/* Wait for the message to clear out. */
+		schedule_timeout(1);
+	}
+
+	/* No need for locks, the interface is down. */
+
+	/*
+	 * Return errors for all pending messages in queue and in the
+	 * tables waiting for remote responses.
+	 */
+	while (!list_empty(&tmplist)) {
+		entry = tmplist.next;
+		list_del(entry);
+		msg = list_entry(entry, struct ipmi_smi_msg, link);
+		deliver_smi_err_response(intf, msg, IPMI_ERR_UNSPECIFIED);
+	}
+
+	for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) {
+		ent = &intf->seq_table[i];
+		if (!ent->inuse)
+			continue;
+		deliver_err_response(intf, ent->recv_msg, IPMI_ERR_UNSPECIFIED);
+	}
+}
+
+void ipmi_unregister_smi(struct ipmi_smi *intf)
+{
+	struct ipmi_smi_watcher *w;
+	int intf_num = intf->intf_num, index;
+
+	mutex_lock(&ipmi_interfaces_mutex);
+	intf->intf_num = -1;
+	intf->in_shutdown = true;
+	list_del_rcu(&intf->link);
+	mutex_unlock(&ipmi_interfaces_mutex);
+	synchronize_srcu(&ipmi_interfaces_srcu);
+
+	/* At this point no users can be added to the interface. */
+
+	/*
+	 * Call all the watcher interfaces to tell them that
+	 * an interface is going away.
+	 */
+	mutex_lock(&smi_watchers_mutex);
+	list_for_each_entry(w, &smi_watchers, link)
+		w->smi_gone(intf_num);
+	mutex_unlock(&smi_watchers_mutex);
+
+	index = srcu_read_lock(&intf->users_srcu);
+	while (!list_empty(&intf->users)) {
+		struct ipmi_user *user =
+			container_of(list_next_rcu(&intf->users),
+				     struct ipmi_user, link);
+
+		_ipmi_destroy_user(user);
+	}
+	srcu_read_unlock(&intf->users_srcu, index);
+
+	if (intf->handlers->shutdown)
+		intf->handlers->shutdown(intf->send_info);
+
+	cleanup_smi_msgs(intf);
+
+	ipmi_bmc_unregister(intf);
+
+	cleanup_srcu_struct(&intf->users_srcu);
+	kref_put(&intf->refcount, intf_free);
+}
+EXPORT_SYMBOL(ipmi_unregister_smi);
+
+static int handle_ipmb_get_msg_rsp(struct ipmi_smi *intf,
+				   struct ipmi_smi_msg *msg)
+{
+	struct ipmi_ipmb_addr ipmb_addr;
+	struct ipmi_recv_msg  *recv_msg;
+
+	/*
+	 * This is 11, not 10, because the response must contain a
+	 * completion code.
+	 */
+	if (msg->rsp_size < 11) {
+		/* Message not big enough, just ignore it. */
+		ipmi_inc_stat(intf, invalid_ipmb_responses);
+		return 0;
+	}
+
+	if (msg->rsp[2] != 0) {
+		/* An error getting the response, just ignore it. */
+		return 0;
+	}
+
+	ipmb_addr.addr_type = IPMI_IPMB_ADDR_TYPE;
+	ipmb_addr.slave_addr = msg->rsp[6];
+	ipmb_addr.channel = msg->rsp[3] & 0x0f;
+	ipmb_addr.lun = msg->rsp[7] & 3;
+
+	/*
+	 * It's a response from a remote entity.  Look up the sequence
+	 * number and handle the response.
+	 */
+	if (intf_find_seq(intf,
+			  msg->rsp[7] >> 2,
+			  msg->rsp[3] & 0x0f,
+			  msg->rsp[8],
+			  (msg->rsp[4] >> 2) & (~1),
+			  (struct ipmi_addr *) &ipmb_addr,
+			  &recv_msg)) {
+		/*
+		 * We were unable to find the sequence number,
+		 * so just nuke the message.
+		 */
+		ipmi_inc_stat(intf, unhandled_ipmb_responses);
+		return 0;
+	}
+
+	memcpy(recv_msg->msg_data, &msg->rsp[9], msg->rsp_size - 9);
+	/*
+	 * The other fields matched, so no need to set them, except
+	 * for netfn, which needs to be the response that was
+	 * returned, not the request value.
+	 */
+	recv_msg->msg.netfn = msg->rsp[4] >> 2;
+	recv_msg->msg.data = recv_msg->msg_data;
+	recv_msg->msg.data_len = msg->rsp_size - 10;
+	recv_msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
+	if (deliver_response(intf, recv_msg))
+		ipmi_inc_stat(intf, unhandled_ipmb_responses);
+	else
+		ipmi_inc_stat(intf, handled_ipmb_responses);
+
+	return 0;
+}
+
+static int handle_ipmb_get_msg_cmd(struct ipmi_smi *intf,
+				   struct ipmi_smi_msg *msg)
+{
+	struct cmd_rcvr          *rcvr;
+	int                      rv = 0;
+	unsigned char            netfn;
+	unsigned char            cmd;
+	unsigned char            chan;
+	struct ipmi_user         *user = NULL;
+	struct ipmi_ipmb_addr    *ipmb_addr;
+	struct ipmi_recv_msg     *recv_msg;
+
+	if (msg->rsp_size < 10) {
+		/* Message not big enough, just ignore it. */
+		ipmi_inc_stat(intf, invalid_commands);
+		return 0;
+	}
+
+	if (msg->rsp[2] != 0) {
+		/* An error getting the response, just ignore it. */
+		return 0;
+	}
+
+	netfn = msg->rsp[4] >> 2;
+	cmd = msg->rsp[8];
+	chan = msg->rsp[3] & 0xf;
+
+	rcu_read_lock();
+	rcvr = find_cmd_rcvr(intf, netfn, cmd, chan);
+	if (rcvr) {
+		user = rcvr->user;
+		kref_get(&user->refcount);
+	} else
+		user = NULL;
+	rcu_read_unlock();
+
+	if (user == NULL) {
+		/* We didn't find a user, deliver an error response. */
+		ipmi_inc_stat(intf, unhandled_commands);
+
+		msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
+		msg->data[1] = IPMI_SEND_MSG_CMD;
+		msg->data[2] = msg->rsp[3];
+		msg->data[3] = msg->rsp[6];
+		msg->data[4] = ((netfn + 1) << 2) | (msg->rsp[7] & 0x3);
+		msg->data[5] = ipmb_checksum(&msg->data[3], 2);
+		msg->data[6] = intf->addrinfo[msg->rsp[3] & 0xf].address;
+		/* rqseq/lun */
+		msg->data[7] = (msg->rsp[7] & 0xfc) | (msg->rsp[4] & 0x3);
+		msg->data[8] = msg->rsp[8]; /* cmd */
+		msg->data[9] = IPMI_INVALID_CMD_COMPLETION_CODE;
+		msg->data[10] = ipmb_checksum(&msg->data[6], 4);
+		msg->data_size = 11;
+
+		ipmi_debug_msg("Invalid command:", msg->data, msg->data_size);
+
+		rcu_read_lock();
+		if (!intf->in_shutdown) {
+			smi_send(intf, intf->handlers, 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 {
+		recv_msg = ipmi_alloc_recv_msg();
+		if (!recv_msg) {
+			/*
+			 * We couldn't allocate memory for the
+			 * message, so requeue it for handling
+			 * later.
+			 */
+			rv = 1;
+			kref_put(&user->refcount, free_user);
+		} else {
+			/* Extract the source address from the data. */
+			ipmb_addr = (struct ipmi_ipmb_addr *) &recv_msg->addr;
+			ipmb_addr->addr_type = IPMI_IPMB_ADDR_TYPE;
+			ipmb_addr->slave_addr = msg->rsp[6];
+			ipmb_addr->lun = msg->rsp[7] & 3;
+			ipmb_addr->channel = msg->rsp[3] & 0xf;
+
+			/*
+			 * Extract the rest of the message information
+			 * from the IPMB header.
+			 */
+			recv_msg->user = user;
+			recv_msg->recv_type = IPMI_CMD_RECV_TYPE;
+			recv_msg->msgid = msg->rsp[7] >> 2;
+			recv_msg->msg.netfn = msg->rsp[4] >> 2;
+			recv_msg->msg.cmd = msg->rsp[8];
+			recv_msg->msg.data = recv_msg->msg_data;
+
+			/*
+			 * We chop off 10, not 9 bytes because the checksum
+			 * at the end also needs to be removed.
+			 */
+			recv_msg->msg.data_len = msg->rsp_size - 10;
+			memcpy(recv_msg->msg_data, &msg->rsp[9],
+			       msg->rsp_size - 10);
+			if (deliver_response(intf, recv_msg))
+				ipmi_inc_stat(intf, unhandled_commands);
+			else
+				ipmi_inc_stat(intf, handled_commands);
+		}
+	}
+
+	return rv;
+}
+
+static int handle_lan_get_msg_rsp(struct ipmi_smi *intf,
+				  struct ipmi_smi_msg *msg)
+{
+	struct ipmi_lan_addr  lan_addr;
+	struct ipmi_recv_msg  *recv_msg;
+
+
+	/*
+	 * This is 13, not 12, because the response must contain a
+	 * completion code.
+	 */
+	if (msg->rsp_size < 13) {
+		/* Message not big enough, just ignore it. */
+		ipmi_inc_stat(intf, invalid_lan_responses);
+		return 0;
+	}
+
+	if (msg->rsp[2] != 0) {
+		/* An error getting the response, just ignore it. */
+		return 0;
+	}
+
+	lan_addr.addr_type = IPMI_LAN_ADDR_TYPE;
+	lan_addr.session_handle = msg->rsp[4];
+	lan_addr.remote_SWID = msg->rsp[8];
+	lan_addr.local_SWID = msg->rsp[5];
+	lan_addr.channel = msg->rsp[3] & 0x0f;
+	lan_addr.privilege = msg->rsp[3] >> 4;
+	lan_addr.lun = msg->rsp[9] & 3;
+
+	/*
+	 * It's a response from a remote entity.  Look up the sequence
+	 * number and handle the response.
+	 */
+	if (intf_find_seq(intf,
+			  msg->rsp[9] >> 2,
+			  msg->rsp[3] & 0x0f,
+			  msg->rsp[10],
+			  (msg->rsp[6] >> 2) & (~1),
+			  (struct ipmi_addr *) &lan_addr,
+			  &recv_msg)) {
+		/*
+		 * We were unable to find the sequence number,
+		 * so just nuke the message.
+		 */
+		ipmi_inc_stat(intf, unhandled_lan_responses);
+		return 0;
+	}
+
+	memcpy(recv_msg->msg_data, &msg->rsp[11], msg->rsp_size - 11);
+	/*
+	 * The other fields matched, so no need to set them, except
+	 * for netfn, which needs to be the response that was
+	 * returned, not the request value.
+	 */
+	recv_msg->msg.netfn = msg->rsp[6] >> 2;
+	recv_msg->msg.data = recv_msg->msg_data;
+	recv_msg->msg.data_len = msg->rsp_size - 12;
+	recv_msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
+	if (deliver_response(intf, recv_msg))
+		ipmi_inc_stat(intf, unhandled_lan_responses);
+	else
+		ipmi_inc_stat(intf, handled_lan_responses);
+
+	return 0;
+}
+
+static int handle_lan_get_msg_cmd(struct ipmi_smi *intf,
+				  struct ipmi_smi_msg *msg)
+{
+	struct cmd_rcvr          *rcvr;
+	int                      rv = 0;
+	unsigned char            netfn;
+	unsigned char            cmd;
+	unsigned char            chan;
+	struct ipmi_user         *user = NULL;
+	struct ipmi_lan_addr     *lan_addr;
+	struct ipmi_recv_msg     *recv_msg;
+
+	if (msg->rsp_size < 12) {
+		/* Message not big enough, just ignore it. */
+		ipmi_inc_stat(intf, invalid_commands);
+		return 0;
+	}
+
+	if (msg->rsp[2] != 0) {
+		/* An error getting the response, just ignore it. */
+		return 0;
+	}
+
+	netfn = msg->rsp[6] >> 2;
+	cmd = msg->rsp[10];
+	chan = msg->rsp[3] & 0xf;
+
+	rcu_read_lock();
+	rcvr = find_cmd_rcvr(intf, netfn, cmd, chan);
+	if (rcvr) {
+		user = rcvr->user;
+		kref_get(&user->refcount);
+	} else
+		user = NULL;
+	rcu_read_unlock();
+
+	if (user == NULL) {
+		/* We didn't find a user, just give up. */
+		ipmi_inc_stat(intf, unhandled_commands);
+
+		/*
+		 * Don't do anything with these messages, just allow
+		 * them to be freed.
+		 */
+		rv = 0;
+	} else {
+		recv_msg = ipmi_alloc_recv_msg();
+		if (!recv_msg) {
+			/*
+			 * We couldn't allocate memory for the
+			 * message, so requeue it for handling later.
+			 */
+			rv = 1;
+			kref_put(&user->refcount, free_user);
+		} else {
+			/* Extract the source address from the data. */
+			lan_addr = (struct ipmi_lan_addr *) &recv_msg->addr;
+			lan_addr->addr_type = IPMI_LAN_ADDR_TYPE;
+			lan_addr->session_handle = msg->rsp[4];
+			lan_addr->remote_SWID = msg->rsp[8];
+			lan_addr->local_SWID = msg->rsp[5];
+			lan_addr->lun = msg->rsp[9] & 3;
+			lan_addr->channel = msg->rsp[3] & 0xf;
+			lan_addr->privilege = msg->rsp[3] >> 4;
+
+			/*
+			 * Extract the rest of the message information
+			 * from the IPMB header.
+			 */
+			recv_msg->user = user;
+			recv_msg->recv_type = IPMI_CMD_RECV_TYPE;
+			recv_msg->msgid = msg->rsp[9] >> 2;
+			recv_msg->msg.netfn = msg->rsp[6] >> 2;
+			recv_msg->msg.cmd = msg->rsp[10];
+			recv_msg->msg.data = recv_msg->msg_data;
+
+			/*
+			 * We chop off 12, not 11 bytes because the checksum
+			 * at the end also needs to be removed.
+			 */
+			recv_msg->msg.data_len = msg->rsp_size - 12;
+			memcpy(recv_msg->msg_data, &msg->rsp[11],
+			       msg->rsp_size - 12);
+			if (deliver_response(intf, recv_msg))
+				ipmi_inc_stat(intf, unhandled_commands);
+			else
+				ipmi_inc_stat(intf, handled_commands);
+		}
+	}
+
+	return rv;
+}
+
+/*
+ * This routine will handle "Get Message" command responses with
+ * channels that use an OEM Medium. The message format belongs to
+ * the OEM.  See IPMI 2.0 specification, Chapter 6 and
+ * Chapter 22, sections 22.6 and 22.24 for more details.
+ */
+static int handle_oem_get_msg_cmd(struct ipmi_smi *intf,
+				  struct ipmi_smi_msg *msg)
+{
+	struct cmd_rcvr       *rcvr;
+	int                   rv = 0;
+	unsigned char         netfn;
+	unsigned char         cmd;
+	unsigned char         chan;
+	struct ipmi_user *user = NULL;
+	struct ipmi_system_interface_addr *smi_addr;
+	struct ipmi_recv_msg  *recv_msg;
+
+	/*
+	 * We expect the OEM SW to perform error checking
+	 * so we just do some basic sanity checks
+	 */
+	if (msg->rsp_size < 4) {
+		/* Message not big enough, just ignore it. */
+		ipmi_inc_stat(intf, invalid_commands);
+		return 0;
+	}
+
+	if (msg->rsp[2] != 0) {
+		/* An error getting the response, just ignore it. */
+		return 0;
+	}
+
+	/*
+	 * This is an OEM Message so the OEM needs to know how
+	 * handle the message. We do no interpretation.
+	 */
+	netfn = msg->rsp[0] >> 2;
+	cmd = msg->rsp[1];
+	chan = msg->rsp[3] & 0xf;
+
+	rcu_read_lock();
+	rcvr = find_cmd_rcvr(intf, netfn, cmd, chan);
+	if (rcvr) {
+		user = rcvr->user;
+		kref_get(&user->refcount);
+	} else
+		user = NULL;
+	rcu_read_unlock();
+
+	if (user == NULL) {
+		/* We didn't find a user, just give up. */
+		ipmi_inc_stat(intf, unhandled_commands);
+
+		/*
+		 * Don't do anything with these messages, just allow
+		 * them to be freed.
+		 */
+
+		rv = 0;
+	} else {
+		recv_msg = ipmi_alloc_recv_msg();
+		if (!recv_msg) {
+			/*
+			 * We couldn't allocate memory for the
+			 * message, so requeue it for handling
+			 * later.
+			 */
+			rv = 1;
+			kref_put(&user->refcount, free_user);
+		} else {
+			/*
+			 * OEM Messages are expected to be delivered via
+			 * the system interface to SMS software.  We might
+			 * need to visit this again depending on OEM
+			 * requirements
+			 */
+			smi_addr = ((struct ipmi_system_interface_addr *)
+				    &recv_msg->addr);
+			smi_addr->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
+			smi_addr->channel = IPMI_BMC_CHANNEL;
+			smi_addr->lun = msg->rsp[0] & 3;
+
+			recv_msg->user = user;
+			recv_msg->user_msg_data = NULL;
+			recv_msg->recv_type = IPMI_OEM_RECV_TYPE;
+			recv_msg->msg.netfn = msg->rsp[0] >> 2;
+			recv_msg->msg.cmd = msg->rsp[1];
+			recv_msg->msg.data = recv_msg->msg_data;
+
+			/*
+			 * The message starts at byte 4 which follows the
+			 * the Channel Byte in the "GET MESSAGE" command
+			 */
+			recv_msg->msg.data_len = msg->rsp_size - 4;
+			memcpy(recv_msg->msg_data, &msg->rsp[4],
+			       msg->rsp_size - 4);
+			if (deliver_response(intf, recv_msg))
+				ipmi_inc_stat(intf, unhandled_commands);
+			else
+				ipmi_inc_stat(intf, handled_commands);
+		}
+	}
+
+	return rv;
+}
+
+static void copy_event_into_recv_msg(struct ipmi_recv_msg *recv_msg,
+				     struct ipmi_smi_msg  *msg)
+{
+	struct ipmi_system_interface_addr *smi_addr;
+
+	recv_msg->msgid = 0;
+	smi_addr = (struct ipmi_system_interface_addr *) &recv_msg->addr;
+	smi_addr->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
+	smi_addr->channel = IPMI_BMC_CHANNEL;
+	smi_addr->lun = msg->rsp[0] & 3;
+	recv_msg->recv_type = IPMI_ASYNC_EVENT_RECV_TYPE;
+	recv_msg->msg.netfn = msg->rsp[0] >> 2;
+	recv_msg->msg.cmd = msg->rsp[1];
+	memcpy(recv_msg->msg_data, &msg->rsp[3], msg->rsp_size - 3);
+	recv_msg->msg.data = recv_msg->msg_data;
+	recv_msg->msg.data_len = msg->rsp_size - 3;
+}
+
+static int handle_read_event_rsp(struct ipmi_smi *intf,
+				 struct ipmi_smi_msg *msg)
+{
+	struct ipmi_recv_msg *recv_msg, *recv_msg2;
+	struct list_head     msgs;
+	struct ipmi_user     *user;
+	int rv = 0, deliver_count = 0, index;
+	unsigned long        flags;
+
+	if (msg->rsp_size < 19) {
+		/* Message is too small to be an IPMB event. */
+		ipmi_inc_stat(intf, invalid_events);
+		return 0;
+	}
+
+	if (msg->rsp[2] != 0) {
+		/* An error getting the event, just ignore it. */
+		return 0;
+	}
+
+	INIT_LIST_HEAD(&msgs);
+
+	spin_lock_irqsave(&intf->events_lock, flags);
+
+	ipmi_inc_stat(intf, events);
+
+	/*
+	 * Allocate and fill in one message for every user that is
+	 * getting events.
+	 */
+	index = srcu_read_lock(&intf->users_srcu);
+	list_for_each_entry_rcu(user, &intf->users, link) {
+		if (!user->gets_events)
+			continue;
+
+		recv_msg = ipmi_alloc_recv_msg();
+		if (!recv_msg) {
+			rcu_read_unlock();
+			list_for_each_entry_safe(recv_msg, recv_msg2, &msgs,
+						 link) {
+				list_del(&recv_msg->link);
+				ipmi_free_recv_msg(recv_msg);
+			}
+			/*
+			 * We couldn't allocate memory for the
+			 * message, so requeue it for handling
+			 * later.
+			 */
+			rv = 1;
+			goto out;
+		}
+
+		deliver_count++;
+
+		copy_event_into_recv_msg(recv_msg, msg);
+		recv_msg->user = user;
+		kref_get(&user->refcount);
+		list_add_tail(&recv_msg->link, &msgs);
+	}
+	srcu_read_unlock(&intf->users_srcu, index);
+
+	if (deliver_count) {
+		/* Now deliver all the messages. */
+		list_for_each_entry_safe(recv_msg, recv_msg2, &msgs, link) {
+			list_del(&recv_msg->link);
+			deliver_local_response(intf, recv_msg);
+		}
+	} else if (intf->waiting_events_count < MAX_EVENTS_IN_QUEUE) {
+		/*
+		 * No one to receive the message, put it in queue if there's
+		 * not already too many things in the queue.
+		 */
+		recv_msg = ipmi_alloc_recv_msg();
+		if (!recv_msg) {
+			/*
+			 * We couldn't allocate memory for the
+			 * message, so requeue it for handling
+			 * later.
+			 */
+			rv = 1;
+			goto out;
+		}
+
+		copy_event_into_recv_msg(recv_msg, msg);
+		list_add_tail(&recv_msg->link, &intf->waiting_events);
+		intf->waiting_events_count++;
+	} else if (!intf->event_msg_printed) {
+		/*
+		 * There's too many things in the queue, discard this
+		 * message.
+		 */
+		dev_warn(intf->si_dev,
+			 PFX "Event queue full, discarding incoming events\n");
+		intf->event_msg_printed = 1;
+	}
+
+ out:
+	spin_unlock_irqrestore(&intf->events_lock, flags);
+
+	return rv;
+}
+
+static int handle_bmc_rsp(struct ipmi_smi *intf,
+			  struct ipmi_smi_msg *msg)
+{
+	struct ipmi_recv_msg *recv_msg;
+	struct ipmi_system_interface_addr *smi_addr;
+
+	recv_msg = (struct ipmi_recv_msg *) msg->user_data;
+	if (recv_msg == NULL) {
+		dev_warn(intf->si_dev,
+			 "IPMI message received with no owner. This could be because of a malformed message, or because of a hardware error.  Contact your hardware vender for assistance\n");
+		return 0;
+	}
+
+	recv_msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
+	recv_msg->msgid = msg->msgid;
+	smi_addr = ((struct ipmi_system_interface_addr *)
+		    &recv_msg->addr);
+	smi_addr->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
+	smi_addr->channel = IPMI_BMC_CHANNEL;
+	smi_addr->lun = msg->rsp[0] & 3;
+	recv_msg->msg.netfn = msg->rsp[0] >> 2;
+	recv_msg->msg.cmd = msg->rsp[1];
+	memcpy(recv_msg->msg_data, &msg->rsp[2], msg->rsp_size - 2);
+	recv_msg->msg.data = recv_msg->msg_data;
+	recv_msg->msg.data_len = msg->rsp_size - 2;
+	deliver_local_response(intf, recv_msg);
+
+	return 0;
+}
+
+/*
+ * Handle a received message.  Return 1 if the message should be requeued,
+ * 0 if the message should be freed, or -1 if the message should not
+ * be freed or requeued.
+ */
+static int handle_one_recv_msg(struct ipmi_smi *intf,
+			       struct ipmi_smi_msg *msg)
+{
+	int requeue;
+	int chan;
+
+	ipmi_debug_msg("Recv:", msg->rsp, msg->rsp_size);
+	if (msg->rsp_size < 2) {
+		/* Message is too small to be correct. */
+		dev_warn(intf->si_dev,
+			 PFX "BMC returned to small a message for netfn %x cmd %x, got %d bytes\n",
+			 (msg->data[0] >> 2) | 1, msg->data[1], msg->rsp_size);
+
+		/* Generate an error response for the message. */
+		msg->rsp[0] = msg->data[0] | (1 << 2);
+		msg->rsp[1] = msg->data[1];
+		msg->rsp[2] = IPMI_ERR_UNSPECIFIED;
+		msg->rsp_size = 3;
+	} else if (((msg->rsp[0] >> 2) != ((msg->data[0] >> 2) | 1))
+		   || (msg->rsp[1] != msg->data[1])) {
+		/*
+		 * The NetFN and Command in the response is not even
+		 * marginally correct.
+		 */
+		dev_warn(intf->si_dev,
+			 PFX "BMC returned incorrect response, expected netfn %x cmd %x, got netfn %x cmd %x\n",
+			 (msg->data[0] >> 2) | 1, msg->data[1],
+			 msg->rsp[0] >> 2, msg->rsp[1]);
+
+		/* Generate an error response for the message. */
+		msg->rsp[0] = msg->data[0] | (1 << 2);
+		msg->rsp[1] = msg->data[1];
+		msg->rsp[2] = IPMI_ERR_UNSPECIFIED;
+		msg->rsp_size = 3;
+	}
+
+	if ((msg->rsp[0] == ((IPMI_NETFN_APP_REQUEST|1) << 2))
+	    && (msg->rsp[1] == IPMI_SEND_MSG_CMD)
+	    && (msg->user_data != NULL)) {
+		/*
+		 * It's a response to a response we sent.  For this we
+		 * deliver a send message response to the user.
+		 */
+		struct ipmi_recv_msg *recv_msg = msg->user_data;
+
+		requeue = 0;
+		if (msg->rsp_size < 2)
+			/* Message is too small to be correct. */
+			goto out;
+
+		chan = msg->data[2] & 0x0f;
+		if (chan >= IPMI_MAX_CHANNELS)
+			/* Invalid channel number */
+			goto out;
+
+		if (!recv_msg)
+			goto out;
+
+		recv_msg->recv_type = IPMI_RESPONSE_RESPONSE_TYPE;
+		recv_msg->msg.data = recv_msg->msg_data;
+		recv_msg->msg.data_len = 1;
+		recv_msg->msg_data[0] = msg->rsp[2];
+		deliver_local_response(intf, recv_msg);
+	} else if ((msg->rsp[0] == ((IPMI_NETFN_APP_REQUEST|1) << 2))
+		   && (msg->rsp[1] == IPMI_GET_MSG_CMD)) {
+		struct ipmi_channel   *chans;
+
+		/* It's from the receive queue. */
+		chan = msg->rsp[3] & 0xf;
+		if (chan >= IPMI_MAX_CHANNELS) {
+			/* Invalid channel number */
+			requeue = 0;
+			goto out;
+		}
+
+		/*
+		 * We need to make sure the channels have been initialized.
+		 * The channel_handler routine will set the "curr_channel"
+		 * equal to or greater than IPMI_MAX_CHANNELS when all the
+		 * channels for this interface have been initialized.
+		 */
+		if (!intf->channels_ready) {
+			requeue = 0; /* Throw the message away */
+			goto out;
+		}
+
+		chans = READ_ONCE(intf->channel_list)->c;
+
+		switch (chans[chan].medium) {
+		case IPMI_CHANNEL_MEDIUM_IPMB:
+			if (msg->rsp[4] & 0x04) {
+				/*
+				 * It's a response, so find the
+				 * requesting message and send it up.
+				 */
+				requeue = handle_ipmb_get_msg_rsp(intf, msg);
+			} else {
+				/*
+				 * It's a command to the SMS from some other
+				 * entity.  Handle that.
+				 */
+				requeue = handle_ipmb_get_msg_cmd(intf, msg);
+			}
+			break;
+
+		case IPMI_CHANNEL_MEDIUM_8023LAN:
+		case IPMI_CHANNEL_MEDIUM_ASYNC:
+			if (msg->rsp[6] & 0x04) {
+				/*
+				 * It's a response, so find the
+				 * requesting message and send it up.
+				 */
+				requeue = handle_lan_get_msg_rsp(intf, msg);
+			} else {
+				/*
+				 * It's a command to the SMS from some other
+				 * entity.  Handle that.
+				 */
+				requeue = handle_lan_get_msg_cmd(intf, msg);
+			}
+			break;
+
+		default:
+			/* Check for OEM Channels.  Clients had better
+			   register for these commands. */
+			if ((chans[chan].medium >= IPMI_CHANNEL_MEDIUM_OEM_MIN)
+			    && (chans[chan].medium
+				<= IPMI_CHANNEL_MEDIUM_OEM_MAX)) {
+				requeue = handle_oem_get_msg_cmd(intf, msg);
+			} else {
+				/*
+				 * We don't handle the channel type, so just
+				 * free the message.
+				 */
+				requeue = 0;
+			}
+		}
+
+	} else if ((msg->rsp[0] == ((IPMI_NETFN_APP_REQUEST|1) << 2))
+		   && (msg->rsp[1] == IPMI_READ_EVENT_MSG_BUFFER_CMD)) {
+		/* It's an asynchronous event. */
+		requeue = handle_read_event_rsp(intf, msg);
+	} else {
+		/* It's a response from the local BMC. */
+		requeue = handle_bmc_rsp(intf, msg);
+	}
+
+ out:
+	return requeue;
+}
+
+/*
+ * If there are messages in the queue or pretimeouts, handle them.
+ */
+static void handle_new_recv_msgs(struct ipmi_smi *intf)
+{
+	struct ipmi_smi_msg  *smi_msg;
+	unsigned long        flags = 0;
+	int                  rv;
+	int                  run_to_completion = intf->run_to_completion;
+
+	/* See if any waiting messages need to be processed. */
+	if (!run_to_completion)
+		spin_lock_irqsave(&intf->waiting_rcv_msgs_lock, flags);
+	while (!list_empty(&intf->waiting_rcv_msgs)) {
+		smi_msg = list_entry(intf->waiting_rcv_msgs.next,
+				     struct ipmi_smi_msg, link);
+		list_del(&smi_msg->link);
+		if (!run_to_completion)
+			spin_unlock_irqrestore(&intf->waiting_rcv_msgs_lock,
+					       flags);
+		rv = handle_one_recv_msg(intf, smi_msg);
+		if (!run_to_completion)
+			spin_lock_irqsave(&intf->waiting_rcv_msgs_lock, flags);
+		if (rv > 0) {
+			/*
+			 * To preserve message order, quit if we
+			 * can't handle a message.  Add the message
+			 * back at the head, this is safe because this
+			 * tasklet is the only thing that pulls the
+			 * messages.
+			 */
+			list_add(&smi_msg->link, &intf->waiting_rcv_msgs);
+			break;
+		} else {
+			if (rv == 0)
+				/* Message handled */
+				ipmi_free_smi_msg(smi_msg);
+			/* If rv < 0, fatal error, del but don't free. */
+		}
+	}
+	if (!run_to_completion)
+		spin_unlock_irqrestore(&intf->waiting_rcv_msgs_lock, flags);
+
+	/*
+	 * If the pretimout count is non-zero, decrement one from it and
+	 * deliver pretimeouts to all the users.
+	 */
+	if (atomic_add_unless(&intf->watchdog_pretimeouts_to_deliver, -1, 0)) {
+		struct ipmi_user *user;
+		int index;
+
+		index = srcu_read_lock(&intf->users_srcu);
+		list_for_each_entry_rcu(user, &intf->users, link) {
+			if (user->handler->ipmi_watchdog_pretimeout)
+				user->handler->ipmi_watchdog_pretimeout(
+					user->handler_data);
+		}
+		srcu_read_unlock(&intf->users_srcu, index);
+	}
+}
+
+static void smi_recv_tasklet(unsigned long val)
+{
+	unsigned long flags = 0; /* keep us warning-free. */
+	struct ipmi_smi *intf = (struct ipmi_smi *) val;
+	int run_to_completion = intf->run_to_completion;
+	struct ipmi_smi_msg *newmsg = NULL;
+
+	/*
+	 * Start the next message if available.
+	 *
+	 * Do this here, not in the actual receiver, because we may deadlock
+	 * because the lower layer is allowed to hold locks while calling
+	 * message delivery.
+	 */
+
+	rcu_read_lock();
+
+	if (!run_to_completion)
+		spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
+	if (intf->curr_msg == NULL && !intf->in_shutdown) {
+		struct list_head *entry = NULL;
+
+		/* Pick the high priority queue first. */
+		if (!list_empty(&intf->hp_xmit_msgs))
+			entry = intf->hp_xmit_msgs.next;
+		else if (!list_empty(&intf->xmit_msgs))
+			entry = intf->xmit_msgs.next;
+
+		if (entry) {
+			list_del(entry);
+			newmsg = list_entry(entry, struct ipmi_smi_msg, link);
+			intf->curr_msg = newmsg;
+		}
+	}
+	if (!run_to_completion)
+		spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
+	if (newmsg)
+		intf->handlers->sender(intf->send_info, newmsg);
+
+	rcu_read_unlock();
+
+	handle_new_recv_msgs(intf);
+}
+
+/* Handle a new message from the lower layer. */
+void ipmi_smi_msg_received(struct ipmi_smi *intf,
+			   struct ipmi_smi_msg *msg)
+{
+	unsigned long flags = 0; /* keep us warning-free. */
+	int run_to_completion = intf->run_to_completion;
+
+	if ((msg->data_size >= 2)
+	    && (msg->data[0] == (IPMI_NETFN_APP_REQUEST << 2))
+	    && (msg->data[1] == IPMI_SEND_MSG_CMD)
+	    && (msg->user_data == NULL)) {
+
+		if (intf->in_shutdown)
+			goto free_msg;
+
+		/*
+		 * This is the local response to a command send, start
+		 * the timer for these.  The user_data will not be
+		 * NULL if this is a response send, and we will let
+		 * response sends just go through.
+		 */
+
+		/*
+		 * Check for errors, if we get certain errors (ones
+		 * that mean basically we can try again later), we
+		 * ignore them and start the timer.  Otherwise we
+		 * 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_BUS_ERR)
+		    && (msg->rsp[2] != IPMI_NAK_ON_WRITE_ERR)) {
+			int ch = msg->rsp[3] & 0xf;
+			struct ipmi_channel *chans;
+
+			/* Got an error sending the message, handle it. */
+
+			chans = READ_ONCE(intf->channel_list)->c;
+			if ((chans[ch].medium == IPMI_CHANNEL_MEDIUM_8023LAN)
+			    || (chans[ch].medium == IPMI_CHANNEL_MEDIUM_ASYNC))
+				ipmi_inc_stat(intf, sent_lan_command_errs);
+			else
+				ipmi_inc_stat(intf, sent_ipmb_command_errs);
+			intf_err_seq(intf, msg->msgid, msg->rsp[2]);
+		} else
+			/* The message was sent, start the timer. */
+			intf_start_seq_timer(intf, msg->msgid);
+
+free_msg:
+		ipmi_free_smi_msg(msg);
+	} else {
+		/*
+		 * To preserve message order, we keep a queue and deliver from
+		 * a tasklet.
+		 */
+		if (!run_to_completion)
+			spin_lock_irqsave(&intf->waiting_rcv_msgs_lock, flags);
+		list_add_tail(&msg->link, &intf->waiting_rcv_msgs);
+		if (!run_to_completion)
+			spin_unlock_irqrestore(&intf->waiting_rcv_msgs_lock,
+					       flags);
+	}
+
+	if (!run_to_completion)
+		spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
+	/*
+	 * We can get an asynchronous event or receive message in addition
+	 * to commands we send.
+	 */
+	if (msg == intf->curr_msg)
+		intf->curr_msg = NULL;
+	if (!run_to_completion)
+		spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
+
+	if (run_to_completion)
+		smi_recv_tasklet((unsigned long) intf);
+	else
+		tasklet_schedule(&intf->recv_tasklet);
+}
+EXPORT_SYMBOL(ipmi_smi_msg_received);
+
+void ipmi_smi_watchdog_pretimeout(struct ipmi_smi *intf)
+{
+	if (intf->in_shutdown)
+		return;
+
+	atomic_set(&intf->watchdog_pretimeouts_to_deliver, 1);
+	tasklet_schedule(&intf->recv_tasklet);
+}
+EXPORT_SYMBOL(ipmi_smi_watchdog_pretimeout);
+
+static struct ipmi_smi_msg *
+smi_from_recv_msg(struct ipmi_smi *intf, struct ipmi_recv_msg *recv_msg,
+		  unsigned char seq, long seqid)
+{
+	struct ipmi_smi_msg *smi_msg = ipmi_alloc_smi_msg();
+	if (!smi_msg)
+		/*
+		 * If we can't allocate the message, then just return, we
+		 * get 4 retries, so this should be ok.
+		 */
+		return NULL;
+
+	memcpy(smi_msg->data, recv_msg->msg.data, recv_msg->msg.data_len);
+	smi_msg->data_size = recv_msg->msg.data_len;
+	smi_msg->msgid = STORE_SEQ_IN_MSGID(seq, seqid);
+
+	ipmi_debug_msg("Resend: ", smi_msg->data, smi_msg->data_size);
+
+	return smi_msg;
+}
+
+static void check_msg_timeout(struct ipmi_smi *intf, struct seq_table *ent,
+			      struct list_head *timeouts,
+			      unsigned long timeout_period,
+			      int slot, unsigned long *flags,
+			      unsigned int *waiting_msgs)
+{
+	struct ipmi_recv_msg *msg;
+
+	if (intf->in_shutdown)
+		return;
+
+	if (!ent->inuse)
+		return;
+
+	if (timeout_period < ent->timeout) {
+		ent->timeout -= timeout_period;
+		(*waiting_msgs)++;
+		return;
+	}
+
+	if (ent->retries_left == 0) {
+		/* The message has used all its retries. */
+		ent->inuse = 0;
+		msg = ent->recv_msg;
+		list_add_tail(&msg->link, timeouts);
+		if (ent->broadcast)
+			ipmi_inc_stat(intf, timed_out_ipmb_broadcasts);
+		else if (is_lan_addr(&ent->recv_msg->addr))
+			ipmi_inc_stat(intf, timed_out_lan_commands);
+		else
+			ipmi_inc_stat(intf, timed_out_ipmb_commands);
+	} else {
+		struct ipmi_smi_msg *smi_msg;
+		/* More retries, send again. */
+
+		(*waiting_msgs)++;
+
+		/*
+		 * Start with the max timer, set to normal timer after
+		 * the message is sent.
+		 */
+		ent->timeout = MAX_MSG_TIMEOUT;
+		ent->retries_left--;
+		smi_msg = smi_from_recv_msg(intf, ent->recv_msg, slot,
+					    ent->seqid);
+		if (!smi_msg) {
+			if (is_lan_addr(&ent->recv_msg->addr))
+				ipmi_inc_stat(intf,
+					      dropped_rexmit_lan_commands);
+			else
+				ipmi_inc_stat(intf,
+					      dropped_rexmit_ipmb_commands);
+			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.
+		 */
+		if (intf->handlers) {
+			if (is_lan_addr(&ent->recv_msg->addr))
+				ipmi_inc_stat(intf,
+					      retransmitted_lan_commands);
+			else
+				ipmi_inc_stat(intf,
+					      retransmitted_ipmb_commands);
+
+			smi_send(intf, intf->handlers, smi_msg, 0);
+		} else
+			ipmi_free_smi_msg(smi_msg);
+
+		spin_lock_irqsave(&intf->seq_lock, *flags);
+	}
+}
+
+static unsigned int ipmi_timeout_handler(struct ipmi_smi *intf,
+					 unsigned long timeout_period)
+{
+	struct list_head     timeouts;
+	struct ipmi_recv_msg *msg, *msg2;
+	unsigned long        flags;
+	int                  i;
+	unsigned int         waiting_msgs = 0;
+
+	if (!intf->bmc_registered) {
+		kref_get(&intf->refcount);
+		if (!schedule_work(&intf->bmc_reg_work)) {
+			kref_put(&intf->refcount, intf_free);
+			waiting_msgs++;
+		}
+	}
+
+	/*
+	 * 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);
+	if (intf->ipmb_maintenance_mode_timeout) {
+		if (intf->ipmb_maintenance_mode_timeout <= timeout_period)
+			intf->ipmb_maintenance_mode_timeout = 0;
+		else
+			intf->ipmb_maintenance_mode_timeout -= timeout_period;
+	}
+	for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++)
+		check_msg_timeout(intf, &intf->seq_table[i],
+				  &timeouts, timeout_period, i,
+				  &flags, &waiting_msgs);
+	spin_unlock_irqrestore(&intf->seq_lock, flags);
+
+	list_for_each_entry_safe(msg, msg2, &timeouts, link)
+		deliver_err_response(intf, 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 = false;
+				maintenance_mode_update(intf);
+			}
+		}
+		spin_unlock_irqrestore(&intf->maintenance_mode_lock,
+				       flags);
+	}
+
+	tasklet_schedule(&intf->recv_tasklet);
+
+	return waiting_msgs;
+}
+
+static void ipmi_request_event(struct ipmi_smi *intf)
+{
+	/* No event requests when in maintenance mode. */
+	if (intf->maintenance_mode_enable)
+		return;
+
+	if (!intf->in_shutdown)
+		intf->handlers->request_events(intf->send_info);
+}
+
+static struct timer_list ipmi_timer;
+
+static atomic_t stop_operation;
+
+static void ipmi_timeout(struct timer_list *unused)
+{
+	struct ipmi_smi *intf;
+	int nt = 0, index;
+
+	if (atomic_read(&stop_operation))
+		return;
+
+	index = srcu_read_lock(&ipmi_interfaces_srcu);
+	list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
+		int lnt = 0;
+
+		if (atomic_read(&intf->event_waiters)) {
+			intf->ticks_to_req_ev--;
+			if (intf->ticks_to_req_ev == 0) {
+				ipmi_request_event(intf);
+				intf->ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
+			}
+			lnt++;
+		}
+
+		lnt += ipmi_timeout_handler(intf, IPMI_TIMEOUT_TIME);
+
+		lnt = !!lnt;
+		if (lnt != intf->last_needs_timer &&
+					intf->handlers->set_need_watch)
+			intf->handlers->set_need_watch(intf->send_info, lnt);
+		intf->last_needs_timer = lnt;
+
+		nt += lnt;
+	}
+	srcu_read_unlock(&ipmi_interfaces_srcu, index);
+
+	if (nt)
+		mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
+}
+
+static void need_waiter(struct ipmi_smi *intf)
+{
+	/* Racy, but worst case we start the timer twice. */
+	if (!timer_pending(&ipmi_timer))
+		mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
+}
+
+static atomic_t smi_msg_inuse_count = ATOMIC_INIT(0);
+static atomic_t recv_msg_inuse_count = ATOMIC_INIT(0);
+
+static void free_smi_msg(struct ipmi_smi_msg *msg)
+{
+	atomic_dec(&smi_msg_inuse_count);
+	kfree(msg);
+}
+
+struct ipmi_smi_msg *ipmi_alloc_smi_msg(void)
+{
+	struct ipmi_smi_msg *rv;
+	rv = kmalloc(sizeof(struct ipmi_smi_msg), GFP_ATOMIC);
+	if (rv) {
+		rv->done = free_smi_msg;
+		rv->user_data = NULL;
+		atomic_inc(&smi_msg_inuse_count);
+	}
+	return rv;
+}
+EXPORT_SYMBOL(ipmi_alloc_smi_msg);
+
+static void free_recv_msg(struct ipmi_recv_msg *msg)
+{
+	atomic_dec(&recv_msg_inuse_count);
+	kfree(msg);
+}
+
+static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void)
+{
+	struct ipmi_recv_msg *rv;
+
+	rv = kmalloc(sizeof(struct ipmi_recv_msg), GFP_ATOMIC);
+	if (rv) {
+		rv->user = NULL;
+		rv->done = free_recv_msg;
+		atomic_inc(&recv_msg_inuse_count);
+	}
+	return rv;
+}
+
+void ipmi_free_recv_msg(struct ipmi_recv_msg *msg)
+{
+	if (msg->user)
+		kref_put(&msg->user->refcount, free_user);
+	msg->done(msg);
+}
+EXPORT_SYMBOL(ipmi_free_recv_msg);
+
+static atomic_t panic_done_count = ATOMIC_INIT(0);
+
+static void dummy_smi_done_handler(struct ipmi_smi_msg *msg)
+{
+	atomic_dec(&panic_done_count);
+}
+
+static void dummy_recv_done_handler(struct ipmi_recv_msg *msg)
+{
+	atomic_dec(&panic_done_count);
+}
+
+/*
+ * Inside a panic, send a message and wait for a response.
+ */
+static void ipmi_panic_request_and_wait(struct ipmi_smi *intf,
+					struct ipmi_addr *addr,
+					struct kernel_ipmi_msg *msg)
+{
+	struct ipmi_smi_msg  smi_msg;
+	struct ipmi_recv_msg recv_msg;
+	int rv;
+
+	smi_msg.done = dummy_smi_done_handler;
+	recv_msg.done = dummy_recv_done_handler;
+	atomic_add(2, &panic_done_count);
+	rv = i_ipmi_request(NULL,
+			    intf,
+			    addr,
+			    0,
+			    msg,
+			    intf,
+			    &smi_msg,
+			    &recv_msg,
+			    0,
+			    intf->addrinfo[0].address,
+			    intf->addrinfo[0].lun,
+			    0, 1); /* Don't retry, and don't wait. */
+	if (rv)
+		atomic_sub(2, &panic_done_count);
+	else if (intf->handlers->flush_messages)
+		intf->handlers->flush_messages(intf->send_info);
+
+	while (atomic_read(&panic_done_count) != 0)
+		ipmi_poll(intf);
+}
+
+static void event_receiver_fetcher(struct ipmi_smi *intf,
+				   struct ipmi_recv_msg *msg)
+{
+	if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
+	    && (msg->msg.netfn == IPMI_NETFN_SENSOR_EVENT_RESPONSE)
+	    && (msg->msg.cmd == IPMI_GET_EVENT_RECEIVER_CMD)
+	    && (msg->msg.data[0] == IPMI_CC_NO_ERROR)) {
+		/* A get event receiver command, save it. */
+		intf->event_receiver = msg->msg.data[1];
+		intf->event_receiver_lun = msg->msg.data[2] & 0x3;
+	}
+}
+
+static void device_id_fetcher(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
+{
+	if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
+	    && (msg->msg.netfn == IPMI_NETFN_APP_RESPONSE)
+	    && (msg->msg.cmd == IPMI_GET_DEVICE_ID_CMD)
+	    && (msg->msg.data[0] == IPMI_CC_NO_ERROR)) {
+		/*
+		 * A get device id command, save if we are an event
+		 * receiver or generator.
+		 */
+		intf->local_sel_device = (msg->msg.data[6] >> 2) & 1;
+		intf->local_event_generator = (msg->msg.data[6] >> 5) & 1;
+	}
+}
+
+static void send_panic_events(struct ipmi_smi *intf, char *str)
+{
+	struct kernel_ipmi_msg msg;
+	unsigned char data[16];
+	struct ipmi_system_interface_addr *si;
+	struct ipmi_addr addr;
+	char *p = str;
+	struct ipmi_ipmb_addr *ipmb;
+	int j;
+
+	if (ipmi_send_panic_event == IPMI_SEND_PANIC_EVENT_NONE)
+		return;
+
+	si = (struct ipmi_system_interface_addr *) &addr;
+	si->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
+	si->channel = IPMI_BMC_CHANNEL;
+	si->lun = 0;
+
+	/* Fill in an event telling that we have failed. */
+	msg.netfn = 0x04; /* Sensor or Event. */
+	msg.cmd = 2; /* Platform event command. */
+	msg.data = data;
+	msg.data_len = 8;
+	data[0] = 0x41; /* Kernel generator ID, IPMI table 5-4 */
+	data[1] = 0x03; /* This is for IPMI 1.0. */
+	data[2] = 0x20; /* OS Critical Stop, IPMI table 36-3 */
+	data[4] = 0x6f; /* Sensor specific, IPMI table 36-1 */
+	data[5] = 0xa1; /* Runtime stop OEM bytes 2 & 3. */
+
+	/*
+	 * Put a few breadcrumbs in.  Hopefully later we can add more things
+	 * to make the panic events more useful.
+	 */
+	if (str) {
+		data[3] = str[0];
+		data[6] = str[1];
+		data[7] = str[2];
+	}
+
+	/* Send the event announcing the panic. */
+	ipmi_panic_request_and_wait(intf, &addr, &msg);
+
+	/*
+	 * On every interface, dump a bunch of OEM event holding the
+	 * string.
+	 */
+	if (ipmi_send_panic_event != IPMI_SEND_PANIC_EVENT_STRING || !str)
+		return;
+
+	/*
+	 * intf_num is used as an marker to tell if the
+	 * interface is valid.  Thus we need a read barrier to
+	 * make sure data fetched before checking intf_num
+	 * won't be used.
+	 */
+	smp_rmb();
+
+	/*
+	 * First job here is to figure out where to send the
+	 * OEM events.  There's no way in IPMI to send OEM
+	 * events using an event send command, so we have to
+	 * find the SEL to put them in and stick them in
+	 * there.
+	 */
+
+	/* Get capabilities from the get device id. */
+	intf->local_sel_device = 0;
+	intf->local_event_generator = 0;
+	intf->event_receiver = 0;
+
+	/* Request the device info from the local MC. */
+	msg.netfn = IPMI_NETFN_APP_REQUEST;
+	msg.cmd = IPMI_GET_DEVICE_ID_CMD;
+	msg.data = NULL;
+	msg.data_len = 0;
+	intf->null_user_handler = device_id_fetcher;
+	ipmi_panic_request_and_wait(intf, &addr, &msg);
+
+	if (intf->local_event_generator) {
+		/* Request the event receiver from the local MC. */
+		msg.netfn = IPMI_NETFN_SENSOR_EVENT_REQUEST;
+		msg.cmd = IPMI_GET_EVENT_RECEIVER_CMD;
+		msg.data = NULL;
+		msg.data_len = 0;
+		intf->null_user_handler = event_receiver_fetcher;
+		ipmi_panic_request_and_wait(intf, &addr, &msg);
+	}
+	intf->null_user_handler = NULL;
+
+	/*
+	 * Validate the event receiver.  The low bit must not
+	 * be 1 (it must be a valid IPMB address), it cannot
+	 * be zero, and it must not be my address.
+	 */
+	if (((intf->event_receiver & 1) == 0)
+	    && (intf->event_receiver != 0)
+	    && (intf->event_receiver != intf->addrinfo[0].address)) {
+		/*
+		 * The event receiver is valid, send an IPMB
+		 * message.
+		 */
+		ipmb = (struct ipmi_ipmb_addr *) &addr;
+		ipmb->addr_type = IPMI_IPMB_ADDR_TYPE;
+		ipmb->channel = 0; /* FIXME - is this right? */
+		ipmb->lun = intf->event_receiver_lun;
+		ipmb->slave_addr = intf->event_receiver;
+	} else if (intf->local_sel_device) {
+		/*
+		 * The event receiver was not valid (or was
+		 * me), but I am an SEL device, just dump it
+		 * in my SEL.
+		 */
+		si = (struct ipmi_system_interface_addr *) &addr;
+		si->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
+		si->channel = IPMI_BMC_CHANNEL;
+		si->lun = 0;
+	} else
+		return; /* No where to send the event. */
+
+	msg.netfn = IPMI_NETFN_STORAGE_REQUEST; /* Storage. */
+	msg.cmd = IPMI_ADD_SEL_ENTRY_CMD;
+	msg.data = data;
+	msg.data_len = 16;
+
+	j = 0;
+	while (*p) {
+		int size = strlen(p);
+
+		if (size > 11)
+			size = 11;
+		data[0] = 0;
+		data[1] = 0;
+		data[2] = 0xf0; /* OEM event without timestamp. */
+		data[3] = intf->addrinfo[0].address;
+		data[4] = j++; /* sequence # */
+		/*
+		 * Always give 11 bytes, so strncpy will fill
+		 * it with zeroes for me.
+		 */
+		strncpy(data+5, p, 11);
+		p += size;
+
+		ipmi_panic_request_and_wait(intf, &addr, &msg);
+	}
+}
+
+static int has_panicked;
+
+static int panic_event(struct notifier_block *this,
+		       unsigned long         event,
+		       void                  *ptr)
+{
+	struct ipmi_smi *intf;
+	struct ipmi_user *user;
+
+	if (has_panicked)
+		return NOTIFY_DONE;
+	has_panicked = 1;
+
+	/* For every registered interface, set it to run to completion. */
+	list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
+		if (!intf->handlers || intf->intf_num == -1)
+			/* Interface is not ready. */
+			continue;
+
+		if (!intf->handlers->poll)
+			continue;
+
+		/*
+		 * If we were interrupted while locking xmit_msgs_lock or
+		 * waiting_rcv_msgs_lock, the corresponding list may be
+		 * corrupted.  In this case, drop items on the list for
+		 * the safety.
+		 */
+		if (!spin_trylock(&intf->xmit_msgs_lock)) {
+			INIT_LIST_HEAD(&intf->xmit_msgs);
+			INIT_LIST_HEAD(&intf->hp_xmit_msgs);
+		} else
+			spin_unlock(&intf->xmit_msgs_lock);
+
+		if (!spin_trylock(&intf->waiting_rcv_msgs_lock))
+			INIT_LIST_HEAD(&intf->waiting_rcv_msgs);
+		else
+			spin_unlock(&intf->waiting_rcv_msgs_lock);
+
+		intf->run_to_completion = 1;
+		if (intf->handlers->set_run_to_completion)
+			intf->handlers->set_run_to_completion(intf->send_info,
+							      1);
+
+		list_for_each_entry_rcu(user, &intf->users, link) {
+			if (user->handler->ipmi_panic_handler)
+				user->handler->ipmi_panic_handler(
+					user->handler_data);
+		}
+
+		send_panic_events(intf, ptr);
+	}
+
+	return NOTIFY_DONE;
+}
+
+/* Must be called with ipmi_interfaces_mutex held. */
+static int ipmi_register_driver(void)
+{
+	int rv;
+
+	if (drvregistered)
+		return 0;
+
+	rv = driver_register(&ipmidriver.driver);
+	if (rv)
+		pr_err("Could not register IPMI driver\n");
+	else
+		drvregistered = true;
+	return rv;
+}
+
+static struct notifier_block panic_block = {
+	.notifier_call	= panic_event,
+	.next		= NULL,
+	.priority	= 200	/* priority: INT_MAX >= x >= 0 */
+};
+
+static int ipmi_init_msghandler(void)
+{
+	int rv;
+
+	mutex_lock(&ipmi_interfaces_mutex);
+	rv = ipmi_register_driver();
+	if (rv)
+		goto out;
+	if (initialized)
+		goto out;
+
+	rv = init_srcu_struct(&ipmi_interfaces_srcu);
+	if (rv)
+		goto out;
+
+	remove_work_wq = create_singlethread_workqueue("ipmi-msghandler-remove-wq");
+	if (!remove_work_wq) {
+		pr_err("unable to create ipmi-msghandler-remove-wq workqueue");
+		rv = -ENOMEM;
+		goto out_wq;
+	}
+
+	timer_setup(&ipmi_timer, ipmi_timeout, 0);
+	mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
+
+	atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
+
+	initialized = true;
+
+out_wq:
+	if (rv)
+		cleanup_srcu_struct(&ipmi_interfaces_srcu);
+out:
+	mutex_unlock(&ipmi_interfaces_mutex);
+	return rv;
+}
+
+static int __init ipmi_init_msghandler_mod(void)
+{
+	int rv;
+
+	pr_info("version " IPMI_DRIVER_VERSION "\n");
+
+	mutex_lock(&ipmi_interfaces_mutex);
+	rv = ipmi_register_driver();
+	mutex_unlock(&ipmi_interfaces_mutex);
+
+	return rv;
+}
+
+static void __exit cleanup_ipmi(void)
+{
+	int count;
+
+	if (initialized) {
+		destroy_workqueue(remove_work_wq);
+
+		atomic_notifier_chain_unregister(&panic_notifier_list,
+						 &panic_block);
+
+		/*
+		 * This can't be called if any interfaces exist, so no worry
+		 * about shutting down the interfaces.
+		 */
+
+		/*
+		 * Tell the timer to stop, then wait for it to stop.  This
+		 * avoids problems with race conditions removing the timer
+		 * here.
+		 */
+		atomic_inc(&stop_operation);
+		del_timer_sync(&ipmi_timer);
+
+		initialized = false;
+
+		/* Check for buffer leaks. */
+		count = atomic_read(&smi_msg_inuse_count);
+		if (count != 0)
+			pr_warn(PFX "SMI message count %d at exit\n", count);
+		count = atomic_read(&recv_msg_inuse_count);
+		if (count != 0)
+			pr_warn(PFX "recv message count %d at exit\n", count);
+		cleanup_srcu_struct(&ipmi_interfaces_srcu);
+	}
+	if (drvregistered)
+		driver_unregister(&ipmidriver.driver);
+}
+module_exit(cleanup_ipmi);
+
+module_init(ipmi_init_msghandler_mod);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Corey Minyard <minyard@mvista.com>");
+MODULE_DESCRIPTION("Incoming and outgoing message routing for an IPMI"
+		   " interface.");
+MODULE_VERSION(IPMI_DRIVER_VERSION);
+MODULE_SOFTDEP("post: ipmi_devintf");