diff options
| -rw-r--r-- | arch/x86/kernel/sysfb_simplefb.c | 25 |
1 files changed, 17 insertions, 8 deletions
diff --git a/arch/x86/kernel/sysfb_simplefb.c b/arch/x86/kernel/sysfb_simplefb.c index 35b86415871f..85195d447a92 100644 --- a/arch/x86/kernel/sysfb_simplefb.c +++ b/arch/x86/kernel/sysfb_simplefb.c @@ -66,8 +66,8 @@ __init int create_simplefb(const struct screen_info *si, { struct platform_device *pd; struct resource res; - unsigned long len; - u64 base; + u64 base, size; + u32 length; /* * If the 64BIT_BASE capability is set, ext_lfb_base will contain the @@ -82,11 +82,20 @@ __init int create_simplefb(const struct screen_info *si, return -EINVAL; } - /* don't use lfb_size as it may contain the whole VMEM instead of only - * the part that is occupied by the framebuffer */ - len = mode->height * mode->stride; - len = PAGE_ALIGN(len); - if (len > (u64)si->lfb_size << 16) { + /* + * Don't use lfb_size as IORESOURCE size, since it may contain the + * entire VMEM, and thus require huge mappings. Use just the part we + * need, that is, the part where the framebuffer is located. But verify + * that it does not exceed the advertised VMEM. + * Note that in case of VBE, the lfb_size is shifted by 16 bits for + * historical reasons. + */ + size = si->lfb_size; + if (si->orig_video_isVGA == VIDEO_TYPE_VLFB) + size <<= 16; + length = mode->height * mode->stride; + length = PAGE_ALIGN(length); + if (length > size) { printk(KERN_WARNING "sysfb: VRAM smaller than advertised\n"); return -EINVAL; } @@ -96,7 +105,7 @@ __init int create_simplefb(const struct screen_info *si, res.flags = IORESOURCE_MEM | IORESOURCE_BUSY; res.name = simplefb_resname; res.start = base; - res.end = res.start + len - 1; + res.end = res.start + length - 1; if (res.end <= res.start) return -EINVAL; |