--- /dev/null
+The gpiommc configfs context structure needs locking, as configfs
+does not lock access between files.
+
+Index: linux-2.6.25.10/drivers/mmc/host/gpiommc.c
+===================================================================
+--- linux-2.6.25.10.orig/drivers/mmc/host/gpiommc.c 2008-07-21 11:57:01.000000000 +0200
++++ linux-2.6.25.10/drivers/mmc/host/gpiommc.c 2008-07-21 12:01:33.000000000 +0200
+@@ -143,6 +143,8 @@ struct gpiommc_configfs_device {
+ struct platform_device *pdev;
+ /* The configuration */
+ struct gpiommc_platform_data pdata;
++ /* Mutex to protect this structure */
++ struct mutex mutex;
+ };
+
+ #define GPIO_INVALID -1
+@@ -233,6 +235,8 @@ static ssize_t gpiommc_config_attr_show(
+ unsigned int gpio;
+ int err = 0;
+
++ mutex_lock(&dev->mutex);
++
+ if (attr == &gpiommc_attr_DI) {
+ gpio = dev->pdata.pins.gpio_di;
+ if (gpio == GPIO_INVALID)
+@@ -293,6 +297,8 @@ static ssize_t gpiommc_config_attr_show(
+ WARN_ON(1);
+ err = -ENOSYS;
+ out:
++ mutex_unlock(&dev->mutex);
++
+ return err ? err : count;
+ }
+
+@@ -352,6 +358,8 @@ static ssize_t gpiommc_config_attr_store
+ int err = -EINVAL;
+ unsigned long data;
+
++ mutex_lock(&dev->mutex);
++
+ if (attr == &gpiommc_attr_register) {
+ err = strict_strtoul(page, 10, &data);
+ if (err)
+@@ -477,6 +485,8 @@ static ssize_t gpiommc_config_attr_store
+ WARN_ON(1);
+ err = -ENOSYS;
+ out:
++ mutex_unlock(&dev->mutex);
++
+ return err ? err : count;
+ }
+
+@@ -513,6 +523,7 @@ static struct config_item *gpiommc_make_
+ if (!dev)
+ return NULL;
+
++ mutex_init(&dev->mutex);
+ config_item_init_type_name(&dev->item, name,
+ &gpiommc_dev_ci_type);
+