From 44f212eb2aafbd2e62fad86d76200fdafe72cafd Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Thu, 28 Mar 2019 20:34:26 +0100 Subject: [PATCH] efifb: Omit memory map check on legacy boot [ Upstream commit c2999c281ea2d2ebbdfce96cecc7b52e2ae7c406 ] Since the following commit: 38ac0287b7f4 ("fbdev/efifb: Honour UEFI memory map attributes when mapping the FB") efifb_probe() checks its memory range via efi_mem_desc_lookup(), and this leads to a spurious error message: EFI_MEMMAP is not enabled at every boot on KVM. This is quite annoying since the error message appears even if you set "quiet" boot option. Since this happens on legacy boot, which strangely enough exposes a EFI framebuffer via screen_info, let's double check that we are doing an EFI boot before attempting to access the EFI memory map. Reported-by: Takashi Iwai Tested-by: Takashi Iwai Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Jones Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20190328193429.21373-3-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- drivers/video/fbdev/efifb.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c index fd02e8a4841d6..9f39f0c360e0c 100644 --- a/drivers/video/fbdev/efifb.c +++ b/drivers/video/fbdev/efifb.c @@ -464,7 +464,8 @@ static int efifb_probe(struct platform_device *dev) info->apertures->ranges[0].base = efifb_fix.smem_start; info->apertures->ranges[0].size = size_remap; - if (!efi_mem_desc_lookup(efifb_fix.smem_start, &md)) { + if (efi_enabled(EFI_BOOT) && + !efi_mem_desc_lookup(efifb_fix.smem_start, &md)) { if ((efifb_fix.smem_start + efifb_fix.smem_len) > (md.phys_addr + (md.num_pages << EFI_PAGE_SHIFT))) { pr_err("efifb: video memory @ 0x%lx spans multiple EFI memory regions\n", -- 2.47.3