[PATCH] drm/amdgpu: Recover vram from vmbo->shadow rather than vmbo->bo

[Christian König]

Am 27.04.23 um 05:23 schrieb Lin.Cao:
> Vmbo->shadow is used to back vram bo up when vram lost. So that we should set
> shadow as vmbo->shadow to recover vmbo->bo.

Good catch.

>
> Fix: 'commit e18aaea733da ("drm/amdgpu: move shadow_list to amdgpu_bo_vm")'
>
> Signed-off-by: Lin.Cao <lincao12 at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 8 +++++++-
>   1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index e536886f6d42..a3c8216f554a 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -4501,7 +4501,13 @@ static int amdgpu_device_recover_vram(struct amdgpu_device *adev)
>   	dev_info(adev->dev, "recover vram bo from shadow start\n");
>   	mutex_lock(&adev->shadow_list_lock);
>   	list_for_each_entry(vmbo, &adev->shadow_list, shadow_list) {
> -		shadow = &vmbo->bo;
> +
> +		/* If vm is compute context or adev is APU, shadow will be NULL */
> +		if (vmbo->shadow)
> +			shadow = vmbo->shadow;
> +		else
> +			continue;

Better write that as "if (!vmbo->shadow) continue;", apart from that 
looks good to me.

Christian.

> +
>   		/* No need to recover an evicted BO */
>   		if (shadow->tbo.resource->mem_type != TTM_PL_TT ||
>   		    shadow->tbo.resource->start == AMDGPU_BO_INVALID_OFFSET ||