x86/simplefb: Fix overflow causing bogus fall-back

On my MacBook Air lfb_size is 4M, which makes the bitshit
overflow (to 256GB - larger than 32 bits), meaning we fall
back to efifb unnecessarily.

Cast to u64 to avoid the overflow.

Signed-off-by: Tom Gundersen <teg@jklm.no>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Stephen Warren <swarren@nvidia.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Link: http://lkml.kernel.org/r/1380644320-1026-1-git-send-email-teg@jklm.no
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Tom Gundersen 2013-10-01 18:18:40 +02:00 committed by Ingo Molnar
parent 669fc2f0c7
commit e33a29a5ae

View File

@ -72,7 +72,7 @@ __init int create_simplefb(const struct screen_info *si,
* the part that is occupied by the framebuffer */
len = mode->height * mode->stride;
len = PAGE_ALIGN(len);
if (len > si->lfb_size << 16) {
if (len > (u64)si->lfb_size << 16) {
printk(KERN_WARNING "sysfb: VRAM smaller than advertised\n");
return -EINVAL;
}