[PATCH] drm/amdkfd: Add sync after creating vram bo

[Philip Yang]

On 2023-01-09 14:27, Eric Huang wrote:
> There will be data corruption on vram allocated by svm
> if initialization is not being done. Adding sync is to
> resolve this issue.
>
> Signed-off-by: Eric Huang <jinhuieric.huang at amd.com>
> ---
>   drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 7 +++++++
>   1 file changed, 7 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> index b8c9753a4818..344e20306635 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> @@ -574,6 +574,13 @@ svm_range_vram_node_new(struct amdgpu_device *adev, struct svm_range *prange,
>   		goto reserve_bo_failed;
>   	}
>   

Thanks for catching this bug, we could optimize as clear VRAM is only 
needed for partial migration, ex pass the clear flag clear = (cpages != 
npages) from svm_migrate_vma_to_vram -> svm_migrate_copy_to_vram -> 
svm_range_vram_node_new.

Regards,

Philip

> +	r = amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
> +	if (r) {
> +		pr_debug("failed %d to sync bo\n", r);
> +		amdgpu_bo_unreserve(bo);
> +		goto reserve_bo_failed;
> +	}
> +
>   	r = dma_resv_reserve_fences(amdkcl_ttm_resvp(&bo->tbo), 1);
>   	if (r) {
>   		pr_debug("failed %d to reserve bo\n", r);