When CONFIG_EFI is not enabled, we might get an undefined reference to efi_enter_virtual_mode() error, if this efi_enabled() call isn't inlined into start_kernel(). This happens in particular, if start_kernel() is annodated with __no_sanitize_address. Reported-by: kernel test robot <lkp@xxxxxxxxx> Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> --- include/linux/efi.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/include/linux/efi.h b/include/linux/efi.h index 05c47f857383..73db1ae04cef 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -606,7 +606,11 @@ extern void *efi_get_pal_addr (void); extern void efi_map_pal_code (void); extern void efi_memmap_walk (efi_freemem_callback_t callback, void *arg); extern void efi_gettimeofday (struct timespec64 *ts); +#ifdef CONFIG_EFI extern void efi_enter_virtual_mode (void); /* switch EFI to virtual mode, if possible */ +#else +static inline void efi_enter_virtual_mode (void) {} +#endif #ifdef CONFIG_X86 extern efi_status_t efi_query_variable_store(u32 attributes, unsigned long size, -- 2.28.0.163.g6104cc2f0b6-goog