Re: [Intel-gfx] [PATCH - v3] drm/i915: Discard large BIOS framebuffers causing display corruption.

From: Ville Syrjälä
Date: Wed Jan 12 2022 - 08:37:56 EST


On Tue, Jan 11, 2022 at 07:55:22AM +0000, Ashish Arora wrote:
> From: Ashish Arora <ashisharora.linux@xxxxxxxxxxx>
>
> On certain 4k panels and Macs, the BIOS framebuffer is larger than what
> panel requires causing display corruption. Introduce a check for the same.

If a larger fb causes corruption then there is a real bug somewhere.

>
>
> Signed-off-by: Ashish Arora <ashisharora.linux@xxxxxxxxxxx>
> Reviewed-by: Aun-Ali Zaidi <admin@xxxxxxxxxx>
> ---
> V2 :- Use != instead of < and >
> V3 :- Mention Macs (Thanks to Orlando)
> drivers/gpu/drm/i915/display/intel_fbdev.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_fbdev.c b/drivers/gpu/drm/i915/display/intel_fbdev.c
> index 842c04e63..16b1c82b2 100644
> --- a/drivers/gpu/drm/i915/display/intel_fbdev.c
> +++ b/drivers/gpu/drm/i915/display/intel_fbdev.c
> @@ -181,10 +181,10 @@ static int intelfb_create(struct drm_fb_helper *helper,
> int ret;
>
> if (intel_fb &&
> - (sizes->fb_width > intel_fb->base.width ||
> - sizes->fb_height > intel_fb->base.height)) {
> + (sizes->fb_width != intel_fb->base.width ||
> + sizes->fb_height != intel_fb->base.height)) {
> drm_dbg_kms(&dev_priv->drm,
> - "BIOS fb too small (%dx%d), we require (%dx%d),"
> + "BIOS fb not valid (%dx%d), we require (%dx%d),"
> " releasing it\n",
> intel_fb->base.width, intel_fb->base.height,
> sizes->fb_width, sizes->fb_height);
> --
> 2.25.1
>

--
Ville Syrjälä
Intel