Well Coverity probably can't know that and will keep complaining.
Maybe we can add some extra code to point out that old can never be NULL
here?
Regards,
Christian.
Am 03.07.24 um 13:06 schrieb Zhou, Bob:
[AMD Official Use Only - AMD Internal Distribution Only]
Hi Christian
Thanks for your comments.
I miss the before logic has limited the generated pointer.
Regards,
Bob
-----Original Message-----
From: Koenig, Christian <Christian.Koenig@xxxxxxx>
Sent: 2024年7月3日 17:26
To: Zhou, Bob <Bob.Zhou@xxxxxxx>; amd-gfx@xxxxxxxxxxxxxxxxxxxxx; Huang, Tim <Tim.Huang@xxxxxxx>; Zhang, Jesse(Jie) <Jesse.Zhang@xxxxxxx>
Cc: Deucher, Alexander <Alexander.Deucher@xxxxxxx>
Subject: Re: [PATCH] drm/amdgpu: : Fix the null pointer dereference for amdgpu_device_switch_gang
Am 03.07.24 um 11:01 schrieb Bob Zhou:
To avoid null pointer dereference reported by Coverity, so add null
pointer check for the return of amdgpu_device_get_gang().
NAK, that's complete nonsense in the first place.
The pointer is guaranteed to be never NULL or otherwise the logic would have crashed long before.
Regards,
Christian.
Signed-off-by: Bob Zhou <bob.zhou@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index bcacf2e35eba..c1d82c346daa 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -6569,7 +6569,7 @@ struct dma_fence *amdgpu_device_switch_gang(struct amdgpu_device *adev,
if (old == gang)
break;
- if (!dma_fence_is_signaled(old))
+ if (!old || !dma_fence_is_signaled(old))
return old;
} while (cmpxchg((struct dma_fence __force **)&adev->gang_submit,
