[PATCH v2 2/5] efi: provide empty efi_enter_virtual_mode implementation

From: Andrey Konovalov
Date: Tue Aug 04 2020 - 08:42:28 EST

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 */
+static inline void efi_enter_virtual_mode (void) {}
#ifdef CONFIG_X86
extern efi_status_t efi_query_variable_store(u32 attributes,
unsigned long size,