efi/gop: Return EFI_NOT_FOUND if there are no usable GOPs

[ Upstream commit 6fc3cec30dfeee7d3c5db8154016aff9d65503c5 ]

If we don't find a usable instance of the Graphics Output Protocol
(GOP) because none of them have a framebuffer (i.e. they were all
PIXEL_BLT_ONLY), but all the EFI calls succeeded, we will return
EFI_SUCCESS even though we didn't find a usable GOP.

Fix this by explicitly returning EFI_NOT_FOUND if no usable GOPs are
found, allowing the caller to probe for UGA instead.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191206165542.31469-3-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/firmware/efi/libstub/gop.c b/drivers/firmware/efi/libstub/gop.c
index 0101ca4..08f3c1a 100644 (file)
--- a/drivers/firmware/efi/libstub/gop.c
+++ b/drivers/firmware/efi/libstub/gop.c
@@ -119,7 +119,7 @@ setup_gop32(efi_system_table_t *sys_table_arg, struct screen_info *si,
        u64 fb_base;
        struct efi_pixel_bitmask pixel_info;
        int pixel_format;
-       efi_status_t status = EFI_NOT_FOUND;
+       efi_status_t status;
        u32 *handles = (u32 *)(unsigned long)gop_handle;
        int i;
 
@@ -175,7 +175,7 @@ setup_gop32(efi_system_table_t *sys_table_arg, struct screen_info *si,
 
        /* Did we find any GOPs? */
        if (!first_gop)
-               goto out;
+               return EFI_NOT_FOUND;
 
        /* EFI framebuffer */
        si->orig_video_isVGA = VIDEO_TYPE_EFI;
@@ -197,7 +197,7 @@ setup_gop32(efi_system_table_t *sys_table_arg, struct screen_info *si,
        si->lfb_size = si->lfb_linelength * si->lfb_height;
 
        si->capabilities |= VIDEO_CAPABILITY_SKIP_QUIRKS;
-out:
+
        return status;
 }
 
@@ -237,7 +237,7 @@ setup_gop64(efi_system_table_t *sys_table_arg, struct screen_info *si,
        u64 fb_base;
        struct efi_pixel_bitmask pixel_info;
        int pixel_format;
-       efi_status_t status = EFI_NOT_FOUND;
+       efi_status_t status;
        u64 *handles = (u64 *)(unsigned long)gop_handle;
        int i;
 
@@ -293,7 +293,7 @@ setup_gop64(efi_system_table_t *sys_table_arg, struct screen_info *si,
 
        /* Did we find any GOPs? */
        if (!first_gop)
-               goto out;
+               return EFI_NOT_FOUND;
 
        /* EFI framebuffer */
        si->orig_video_isVGA = VIDEO_TYPE_EFI;
@@ -315,7 +315,7 @@ setup_gop64(efi_system_table_t *sys_table_arg, struct screen_info *si,
        si->lfb_size = si->lfb_linelength * si->lfb_height;
 
        si->capabilities |= VIDEO_CAPABILITY_SKIP_QUIRKS;
-out:
+
        return status;
 }