drm/amdgpu: fix drm panic null pointer when driver not support atomic

[PATCH] drm/amdgpu: fix drm panic null pointer when driver not support atomic

Posted by yaolu@kylinos.cn 1 month ago

From: Lu Yao <yaolu@kylinos.cn>

When driver not support atomic, fb using plane->fb rather than
plane->state->fb.

Fixes: fe151ed7af54 ("drm/amdgpu: add generic display panic helper code")
Signed-off-by: Lu Yao <yaolu@kylinos.cn>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_display.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
index b5d34797d606..52bc04452812 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
@@ -1880,7 +1880,12 @@ int amdgpu_display_get_scanout_buffer(struct drm_plane *plane,
 				      struct drm_scanout_buffer *sb)
 {
 	struct amdgpu_bo *abo;
-	struct drm_framebuffer *fb = plane->state->fb;
+	struct drm_framebuffer *fb;
+
+	if (drm_drv_uses_atomic_modeset(plane->dev))
+		fb = plane->state->fb;
+	else
+		fb = plane->fb;
 
 	if (!fb)
 		return -EINVAL;
-- 
2.25.1

Re: [PATCH] drm/amdgpu: fix drm panic null pointer when driver not support atomic

Posted by Alex Deucher 1 month ago

Applied.  Thanks!

On Mon, Jan 5, 2026 at 9:37 PM <yaolu@kylinos.cn> wrote:
>
> From: Lu Yao <yaolu@kylinos.cn>
>
> When driver not support atomic, fb using plane->fb rather than
> plane->state->fb.
>
> Fixes: fe151ed7af54 ("drm/amdgpu: add generic display panic helper code")
> Signed-off-by: Lu Yao <yaolu@kylinos.cn>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_display.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> index b5d34797d606..52bc04452812 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> @@ -1880,7 +1880,12 @@ int amdgpu_display_get_scanout_buffer(struct drm_plane *plane,
>                                       struct drm_scanout_buffer *sb)
>  {
>         struct amdgpu_bo *abo;
> -       struct drm_framebuffer *fb = plane->state->fb;
> +       struct drm_framebuffer *fb;
> +
> +       if (drm_drv_uses_atomic_modeset(plane->dev))
> +               fb = plane->state->fb;
> +       else
> +               fb = plane->fb;
>
>         if (!fb)
>                 return -EINVAL;
> --
> 2.25.1
>