Re: [PATCH AUTOSEL 6.1 5/7] drm/amdgpu: Fix size validation for non-exclusive domains (v4)

[Luben Tuikov]

Hi Sasha,

The patch in the link is a Fixes patch of the quoted patch, and should also go in:

https://lore.kernel.org/all/20230104221935.113400-1-luben.tuikov@xxxxxxx/

Regards,
Luben

On 2022-12-31 15:04, Sasha Levin wrote:
> From: Luben Tuikov <luben.tuikov@xxxxxxx>
> 
> [ Upstream commit 7554886daa31eacc8e7fac9e15bbce67d10b8f1f ]
> 
> Fix amdgpu_bo_validate_size() to check whether the TTM domain manager for the
> requested memory exists, else we get a kernel oops when dereferencing "man".
> 
> v2: Make the patch standalone, i.e. not dependent on local patches.
> v3: Preserve old behaviour and just check that the manager pointer is not
>     NULL.
> v4: Complain if GTT domain requested and it is uninitialized--most likely a
>     bug.
> 
> Cc: Alex Deucher <Alexander.Deucher@xxxxxxx>
> Cc: Christian König <christian.koenig@xxxxxxx>
> Cc: AMD Graphics <amd-gfx@xxxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Luben Tuikov <luben.tuikov@xxxxxxx>
> Reviewed-by: Christian König <christian.koenig@xxxxxxx>
> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 19 ++++++++-----------
>  1 file changed, 8 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> index 2e8f6cd7a729..33e266433e9b 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> @@ -446,27 +446,24 @@ static bool amdgpu_bo_validate_size(struct amdgpu_device *adev,
>  
>  	/*
>  	 * If GTT is part of requested domains the check must succeed to
> -	 * allow fall back to GTT
> +	 * allow fall back to GTT.
>  	 */
>  	if (domain & AMDGPU_GEM_DOMAIN_GTT) {
>  		man = ttm_manager_type(&adev->mman.bdev, TTM_PL_TT);
>  
> -		if (size < man->size)
> +		if (man && size < man->size)
>  			return true;
> -		else
> -			goto fail;
> -	}
> -
> -	if (domain & AMDGPU_GEM_DOMAIN_VRAM) {
> +		else if (!man)
> +			WARN_ON_ONCE("GTT domain requested but GTT mem manager uninitialized");
> +		goto fail;
> +	} else if (domain & AMDGPU_GEM_DOMAIN_VRAM) {
>  		man = ttm_manager_type(&adev->mman.bdev, TTM_PL_VRAM);
>  
> -		if (size < man->size)
> +		if (man && size < man->size)
>  			return true;
> -		else
> -			goto fail;
> +		goto fail;
>  	}
>  
> -
>  	/* TODO add more domains checks, such as AMDGPU_GEM_DOMAIN_CPU */
>  	return true;
>