diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index d4023ea1ccffa044b625f1c0a94ae456ada69a68..52146f95d58e763d90801d44ded1ef86afcdc57d 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -187,8 +187,27 @@ static const struct attribute_group efi_subsys_attr_group = { static struct efivars generic_efivars; static struct efivar_operations generic_ops; +static bool generic_ops_supported(void) +{ + unsigned long name_size; + efi_status_t status; + efi_char16_t name; + efi_guid_t guid; + + name_size = sizeof(name); + + status = efi.get_next_variable(&name_size, &name, &guid); + if (status == EFI_UNSUPPORTED) + return false; + + return true; +} + static int generic_ops_register(void) { + if (!generic_ops_supported()) + return 0; + generic_ops.get_variable = efi.get_variable; generic_ops.get_next_variable = efi.get_next_variable; generic_ops.query_variable_store = efi_query_variable_store; @@ -202,6 +221,9 @@ static int generic_ops_register(void) static void generic_ops_unregister(void) { + if (!generic_ops.get_variable) + return; + efivars_unregister(&generic_efivars); }