Re: [PATCH v2] drm/amdgpu: avoid using null object of framebuffer

["Zhang, Julia" <Julia.Zhang@xxxxxxx>]

 

On 2024/6/19 12:53, Huang Rui wrote:

On Wed, Jun 19, 2024 at 12:46:25PM +0800, Huang Rui wrote:

On Wed, Jun 19, 2024 at 12:29:24PM +0800, Zhang, Julia wrote:

Instead of using state->fb->obj[0] directly, get object from framebuffer

by calling drm_gem_fb_get_obj() and return error code when object is

null to avoid using null object of framebuffer.

v2: Call drm_gem_fb_get_obj after check old_state->fb for NULL.

Signed-off-by: Julia Zhang <Julia.Zhang@xxxxxxx>

---

Julia, you can add my RB during V1 in the next submission.

Reviewed-by: Huang Rui <ray.huang@xxxxxxx>

CC Fusheng who reported the issue.

Fusheng, may we have your reported-by?

Hi Fusheng,

Can you help to review this patch and may we have you reported-by? Thank you.

Julia

 drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c | 18 ++++++++++++++++--

 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c

index d60c4a2eeb0c..212f6522859d 100644

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c

+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c

@@ -2,6 +2,7 @@

 #include <drm/drm_atomic_helper.h>

 #include <drm/drm_simple_kms_helper.h>

+#include <drm/drm_gem_framebuffer_helper.h>

 #include <drm/drm_vblank.h>

 #include "amdgpu.h"

@@ -311,7 +312,13 @@ static int amdgpu_vkms_prepare_fb(struct drm_plane *plane,

             return 0;

     }

     afb = to_amdgpu_framebuffer(new_state->fb);

-    obj = new_state->fb->obj[0];

+

+    obj = drm_gem_fb_get_obj(new_state->fb, 0);

+    if (!obj) {

+        DRM_ERROR("Failed to get obj from framebuffer\n");

+            return -EINVAL;

+    }

+

     rbo = gem_to_amdgpu_bo(obj);

     adev = amdgpu_ttm_adev(rbo->tbo.bdev);

@@ -365,12 +372,19 @@ static void amdgpu_vkms_cleanup_fb(struct drm_plane *plane,

                               struct drm_plane_state *old_state)

 {

     struct amdgpu_bo *rbo;

+    struct drm_gem_object *obj;

     int r;

     if (!old_state->fb)

             return;

-    rbo = gem_to_amdgpu_bo(old_state->fb->obj[0]);

+    obj = drm_gem_fb_get_obj(old_state->fb, 0);

+    if (!obj) {

+        DRM_ERROR("Failed to get obj from framebuffer\n");

+            return;

+    }

+

+    rbo = gem_to_amdgpu_bo(obj);

     r = amdgpu_bo_reserve(rbo, false);

     if (unlikely(r)) {

         DRM_ERROR("failed to reserve rbo before unpin\n");

-- 

2.34.1