2 files changed, 82 insertions, 6 deletions

diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index a64fb7bda365..69225115304d 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -158,6 +158,13 @@ efivar_create_sysfs_entry(struct efivars *efivars,
                           efi_char16_t *variable_name,
                           efi_guid_t *vendor_guid);
 
+/*
+ * Prototype for workqueue functions updating sysfs entry
+ */
+
+static void efivar_update_sysfs_entries(struct work_struct *);
+static DECLARE_WORK(efivar_work, efivar_update_sysfs_entries);
+
 /* Return the number of unicode characters in data */
 static unsigned long
 utf16_strnlen(efi_char16_t *s, size_t maxlength)
@@ -1248,11 +1255,8 @@ static int efi_pstore_write(enum pstore_type_id type,
 
         spin_unlock_irqrestore(&efivars->lock, flags);
 
-        if (size)
-                ret = efivar_create_sysfs_entry(efivars,
-                                          utf16_strsize(efi_name,
-                                                        DUMP_NAME_LEN * 2),
-                                          efi_name, &vendor);
+        if (reason == KMSG_DUMP_OOPS)
+                schedule_work(&efivar_work);
 
         *id = part;
         return ret;
@@ -1496,6 +1500,75 @@ static ssize_t efivar_delete(struct file *filp, struct kobject *kobj,
         return count;
 }
 
+static bool variable_is_present(efi_char16_t *variable_name, efi_guid_t *vendor)
+{
+        struct efivar_entry *entry, *n;
+        struct efivars *efivars = &__efivars;
+        unsigned long strsize1, strsize2;
+        bool found = false;
+
+        strsize1 = utf16_strsize(variable_name, 1024);
+        list_for_each_entry_safe(entry, n, &efivars->list, list) {
+                strsize2 = utf16_strsize(entry->var.VariableName, 1024);
+                if (strsize1 == strsize2 &&
+                        !memcmp(variable_name, &(entry->var.VariableName),
+                                strsize2) &&
+                        !efi_guidcmp(entry->var.VendorGuid,
+                                *vendor)) {
+                        found = true;
+                        break;
+                }
+        }
+        return found;
+}
+
+static void efivar_update_sysfs_entries(struct work_struct *work)
+{
+        struct efivars *efivars = &__efivars;
+        efi_guid_t vendor;
+        efi_char16_t *variable_name;
+        unsigned long variable_name_size = 1024;
+        efi_status_t status = EFI_NOT_FOUND;
+        bool found;
+
+        /* Add new sysfs entries */
+        while (1) {
+                variable_name = kzalloc(variable_name_size, GFP_KERNEL);
+                if (!variable_name) {
+                        pr_err("efivars: Memory allocation failed.\n");
+                        return;
+                }
+
+                spin_lock_irq(&efivars->lock);
+                found = false;
+                while (1) {
+                        variable_name_size = 1024;
+                        status = efivars->ops->get_next_variable(
+                                                        &variable_name_size,
+                                                        variable_name,
+                                                        &vendor);
+                        if (status != EFI_SUCCESS) {
+                                break;
+                        } else {
+                                if (!variable_is_present(variable_name,
+                                    &vendor)) {
+                                        found = true;
+                                        break;
+                                }
+                        }
+                }
+                spin_unlock_irq(&efivars->lock);
+
+                if (!found) {
+                        kfree(variable_name);
+                        break;
+                } else
+                        efivar_create_sysfs_entry(efivars,
+                                                  variable_name_size,
+                                                  variable_name, &vendor);
+        }
+}
+
 /*
  * Let's not leave out systab information that snuck into
  * the efivars driver
@@ -1833,6 +1906,8 @@ err_put:
 static void __exit
 efivars_exit(void)
 {
+        cancel_work_sync(&efivar_work);
+
         if (efi_enabled) {
                 unregister_efivars(&__efivars);
                 kobject_put(efi_kobj);
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 8b84916dc671..d0c68aee0925 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -728,7 +728,8 @@ struct efivars {
          * 1) ->list - adds, removals, reads, writes
          * 2) ops.[gs]et_variable() calls.
          * It must not be held when creating sysfs entries or calling kmalloc.
-         * ops.get_next_variable() is only called from register_efivars(),
+         * ops.get_next_variable() is only called from register_efivars()
+         * or efivar_update_sysfs_entries(),
          * which is protected by the BKL, so that path is safe.
          */
         spinlock_t lock;