When building x86/defconfig with Clang-18 I encounter the following warnings: | arch/x86/platform/efi/efi.c:934:23: warning: no previous extern declaration for non-static variable 'efi_attr_fw_vendor' [-Wmissing-variable-declarations] | 934 | struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor); | arch/x86/platform/efi/efi.c:935:23: warning: no previous extern declaration for non-static variable 'efi_attr_runtime' [-Wmissing-variable-declarations] | 935 | struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime); | arch/x86/platform/efi/efi.c:936:23: warning: no previous extern declaration for non-static variable 'efi_attr_config_table' [-Wmissing-variable-declarations] | 936 | struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table); These symbols are declared extern in drivers/firmware/efi/efi.c. Move the declarations to linux/efi.h to resolve these warnings. Also, trim a trailing space from efi_set_variable_t typedef. Link: https://github.com/ClangBuiltLinux/linux/issues/1920 Suggested-by: Ard Biesheuvel <ardb@xxxxxxxxxx> Signed-off-by: Justin Stitt <justinstitt@xxxxxxxxxx> --- Changes in v2: - Don't use static. Instead move symbols to header file (thanks Ard) - Remove duplicated warnings output from b4 (thanks Ard) - Link to v1: https://lore.kernel.org/r/20230829-missingvardecl-efi-v1-1-13d055a55176@xxxxxxxxxx --- Note: build-tested. Also, a question: Why does the compiler warn at all? The extern declarations _do_ exist as Ard points out [1]. [1]: https://lore.kernel.org/all/CAMj1kXE_xs+wWno4G4U+6CFCOwO7JWcmNv4et5=W=ZRrQatWnQ@xxxxxxxxxxxxxx/ --- drivers/firmware/efi/efi.c | 3 --- include/linux/efi.h | 6 +++++- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 1599f1176842..7b4e59ccf09e 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -161,9 +161,6 @@ static ssize_t fw_platform_size_show(struct kobject *kobj, return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32); } -extern __weak struct kobj_attribute efi_attr_fw_vendor; -extern __weak struct kobj_attribute efi_attr_runtime; -extern __weak struct kobj_attribute efi_attr_config_table; static struct kobj_attribute efi_attr_fw_platform_size = __ATTR_RO(fw_platform_size); diff --git a/include/linux/efi.h b/include/linux/efi.h index ab088c662e88..32f7ca60b0e9 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -287,7 +287,7 @@ typedef efi_status_t efi_get_variable_t (efi_char16_t *name, efi_guid_t *vendor, unsigned long *data_size, void *data); typedef efi_status_t efi_get_next_variable_t (unsigned long *name_size, efi_char16_t *name, efi_guid_t *vendor); -typedef efi_status_t efi_set_variable_t (efi_char16_t *name, efi_guid_t *vendor, +typedef efi_status_t efi_set_variable_t (efi_char16_t *name, efi_guid_t *vendor, u32 attr, unsigned long data_size, void *data); typedef efi_status_t efi_get_next_high_mono_count_t (u32 *count); @@ -632,6 +632,10 @@ typedef struct { extern unsigned long __ro_after_init efi_rng_seed; /* RNG Seed table */ +extern __weak struct kobj_attribute efi_attr_fw_vendor; +extern __weak struct kobj_attribute efi_attr_runtime; +extern __weak struct kobj_attribute efi_attr_config_table; + /* * All runtime access to EFI goes through this structure: */ --- base-commit: 706a741595047797872e669b3101429ab8d378ef change-id: 20230829-missingvardecl-efi-59306aacfed4 Best regards, -- Justin Stitt <justinstitt@xxxxxxxxxx>
