1 files changed, 14 insertions, 10 deletions

diff --git a/drivers/acpi/acpi_ipmi.c b/drivers/acpi/acpi_ipmi.c
index f40acef80269..a6977e12d574 100644
--- a/drivers/acpi/acpi_ipmi.c
+++ b/drivers/acpi/acpi_ipmi.c
@@ -39,6 +39,7 @@
 #include <linux/ipmi.h>
 #include <linux/device.h>
 #include <linux/pnp.h>
+#include <linux/spinlock.h>
 
 MODULE_AUTHOR("Zhao Yakui");
 MODULE_DESCRIPTION("ACPI IPMI Opregion driver");
@@ -57,7 +58,7 @@ struct acpi_ipmi_device {
         struct list_head head;
         /* the IPMI request message list */
         struct list_head tx_msg_list;
-        struct mutex    tx_msg_lock;
+        spinlock_t      tx_msg_lock;
         acpi_handle handle;
         struct pnp_dev *pnp_dev;
         ipmi_user_t     user_interface;
@@ -147,6 +148,7 @@ static void acpi_format_ipmi_msg(struct acpi_ipmi_msg *tx_msg,
         struct kernel_ipmi_msg *msg;
         struct acpi_ipmi_buffer *buffer;
         struct acpi_ipmi_device *device;
+        unsigned long flags;
 
         msg = &tx_msg->tx_message;
         /*
@@ -177,10 +179,10 @@ static void acpi_format_ipmi_msg(struct acpi_ipmi_msg *tx_msg,
 
         /* Get the msgid */
         device = tx_msg->device;
-        mutex_lock(&device->tx_msg_lock);
+        spin_lock_irqsave(&device->tx_msg_lock, flags);
         device->curr_msgid++;
         tx_msg->tx_msgid = device->curr_msgid;
-        mutex_unlock(&device->tx_msg_lock);
+        spin_unlock_irqrestore(&device->tx_msg_lock, flags);
 }
 
 static void acpi_format_ipmi_response(struct acpi_ipmi_msg *msg,
@@ -242,6 +244,7 @@ static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
         int msg_found = 0;
         struct acpi_ipmi_msg *tx_msg;
         struct pnp_dev *pnp_dev = ipmi_device->pnp_dev;
+        unsigned long flags;
 
         if (msg->user != ipmi_device->user_interface) {
                 dev_warn(&pnp_dev->dev, "Unexpected response is returned. "
@@ -250,7 +253,7 @@ static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
                 ipmi_free_recv_msg(msg);
                 return;
         }
-        mutex_lock(&ipmi_device->tx_msg_lock);
+        spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);
         list_for_each_entry(tx_msg, &ipmi_device->tx_msg_list, head) {
                 if (msg->msgid == tx_msg->tx_msgid) {
                         msg_found = 1;
@@ -258,7 +261,7 @@ static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
                 }
         }
 
-        mutex_unlock(&ipmi_device->tx_msg_lock);
+        spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);
         if (!msg_found) {
                 dev_warn(&pnp_dev->dev, "Unexpected response (msg id %ld) is "
                         "returned.\n", msg->msgid);
@@ -378,6 +381,7 @@ acpi_ipmi_space_handler(u32 function, acpi_physical_address address,
         struct acpi_ipmi_device *ipmi_device = handler_context;
         int err, rem_time;
         acpi_status status;
+        unsigned long flags;
         /*
          * IPMI opregion message.
          * IPMI message is firstly written to the BMC and system software
@@ -395,9 +399,9 @@ acpi_ipmi_space_handler(u32 function, acpi_physical_address address,
                 return AE_NO_MEMORY;
 
         acpi_format_ipmi_msg(tx_msg, address, value);
-        mutex_lock(&ipmi_device->tx_msg_lock);
+        spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);
         list_add_tail(&tx_msg->head, &ipmi_device->tx_msg_list);
-        mutex_unlock(&ipmi_device->tx_msg_lock);
+        spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);
         err = ipmi_request_settime(ipmi_device->user_interface,
                                         &tx_msg->addr,
                                         tx_msg->tx_msgid,
@@ -413,9 +417,9 @@ acpi_ipmi_space_handler(u32 function, acpi_physical_address address,
         status = AE_OK;
 
 end_label:
-        mutex_lock(&ipmi_device->tx_msg_lock);
+        spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);
         list_del(&tx_msg->head);
-        mutex_unlock(&ipmi_device->tx_msg_lock);
+        spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);
         kfree(tx_msg);
         return status;
 }
@@ -457,7 +461,7 @@ static void acpi_add_ipmi_device(struct acpi_ipmi_device *ipmi_device)
 
         INIT_LIST_HEAD(&ipmi_device->head);
 
-        mutex_init(&ipmi_device->tx_msg_lock);
+        spin_lock_init(&ipmi_device->tx_msg_lock);
         INIT_LIST_HEAD(&ipmi_device->tx_msg_list);
         ipmi_install_space_handler(ipmi_device);