[RFC v2 06/15] drm/amdgpu: enhance amdgpu_ras_pre_fini() to better support SR

[Mario Limonciello]

On 1/12/2025 19:42, Jiang Liu wrote:
> Enhance amdgpu_ras_pre_fini() to better support suspend/resume by:
> 1) fix possible resource leakage. amdgpu_release_ras_context() only
>     kfree(con) but doesn't release resources associated with the con
>     object.
> 2) call amdgpu_ras_pre_fini() in amdgpu_device_suspend() to undo what
>     has been done by amdgpu_ras_late_init(), because amdgpu_device_resume()
>     will invoke amdgpu_ras_late_init() on resume.
> 3) move amdgpu_ras_recovery_fini() from amdgpu_ras_pre_fini() to
>     amdgpu_ras_fini()
> 4) move calling of `obj->ras_fini()` from amdgpu_ras_fini() to
>     amdgpu_ras_pre_fini().
> 
> Signed-off-by: Jiang Liu <gerry at linux.alibaba.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |  6 ++-
>   drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c    | 44 +++++++++++++---------
>   2 files changed, 31 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 0a121aab5c74..2bfe113e17c7 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -4613,6 +4613,8 @@ int amdgpu_device_init(struct amdgpu_device *adev,
>   	return 0;
>   
>   release_ras_con:
> +	amdgpu_ras_pre_fini(adev);
> +	amdgpu_ras_fini(adev);
>   	if (amdgpu_sriov_vf(adev))
>   		amdgpu_virt_release_full_gpu(adev, true);
>   
> @@ -4627,8 +4629,6 @@ int amdgpu_device_init(struct amdgpu_device *adev,
>   		adev->virt.ops = NULL;
>   		r = -EAGAIN;
>   	}
> -	amdgpu_release_ras_context(adev);
> -
>   failed:
>   	amdgpu_vf_error_trans_all(adev);
>   
> @@ -4921,6 +4921,8 @@ int amdgpu_device_suspend(struct drm_device *dev, bool notify_clients)
>   
>   	cancel_delayed_work_sync(&adev->delayed_init_work);
>   
> +	/* disable ras feature must before hw fini */
> +	amdgpu_ras_pre_fini(adev);
>   	amdgpu_ras_suspend(adev);
>   
>   	amdgpu_device_ip_suspend_phase1(adev);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
> index 7bbab7297c97..5ac63f9cffda 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
> @@ -4270,42 +4270,49 @@ int amdgpu_ras_late_init(struct amdgpu_device *adev)
>   int amdgpu_ras_pre_fini(struct amdgpu_device *adev)
>   {
>   	struct amdgpu_ras *con = amdgpu_ras_get_context(adev);
> +	struct amdgpu_ras_block_list *node, *tmp;
> +	struct amdgpu_ras_block_object *obj;
>   
> -	if (!adev->ras_enabled || !con)
> -		return 0;
> +	if (amdgpu_sriov_vf(adev) && !amdgpu_sriov_ras_telemetry_en(adev))
> +		goto disable;
>   
> +	list_for_each_entry_safe(node, tmp, &adev->ras_list, node) {
> +		obj = node->ras_obj;
> +		if (!obj)
> +			continue;
> +
> +		if (!amdgpu_ras_is_supported(adev, obj->ras_comm.block))
> +			continue;
> +
> +		if (obj->ras_fini)
> +			obj->ras_fini(adev, &obj->ras_comm);
> +		else
> +			amdgpu_ras_block_late_fini_default(adev, &obj->ras_comm);
> +	}
>   
> +disable:
>   	/* Need disable ras on all IPs here before ip [hw/sw]fini */
> -	if (AMDGPU_RAS_GET_FEATURES(con->features))
> +	if (con && AMDGPU_RAS_GET_FEATURES(con->features))
>   		amdgpu_ras_disable_all_features(adev, 0);
> -	amdgpu_ras_recovery_fini(adev);
> +
>   	return 0;
>   }
>   
>   int amdgpu_ras_fini(struct amdgpu_device *adev)
>   {
>   	struct amdgpu_ras_block_list *ras_node, *tmp;
> -	struct amdgpu_ras_block_object *obj = NULL;
>   	struct amdgpu_ras *con = amdgpu_ras_get_context(adev);
>   
>   	if (!adev->ras_enabled || !con)
> -		return 0;
> +		goto out_free_context;

This block doesn't make sense for two reasons.

1) Why would you have a context if adev->ras_enabled was false?
2) If amdgpu_ras_get_context() returned NULL, then jumping to 
out_free_context and checking con again doesn't make sense - you already 
knew it was NULL.

>   
>   	list_for_each_entry_safe(ras_node, tmp, &adev->ras_list, node) {
> -		if (ras_node->ras_obj) {
> -			obj = ras_node->ras_obj;
> -			if (amdgpu_ras_is_supported(adev, obj->ras_comm.block) &&
> -			    obj->ras_fini)
> -				obj->ras_fini(adev, &obj->ras_comm);
> -			else
> -				amdgpu_ras_block_late_fini_default(adev, &obj->ras_comm);
> -		}
> -
>   		/* Clear ras blocks from ras_list and free ras block list node */
>   		list_del(&ras_node->node);
>   		kfree(ras_node);
>   	}
>   
> +	amdgpu_ras_recovery_fini(adev);
>   	amdgpu_ras_fs_fini(adev);
>   	amdgpu_ras_interrupt_remove_all(adev);
>   
> @@ -4323,8 +4330,11 @@ int amdgpu_ras_fini(struct amdgpu_device *adev)
>   
>   	cancel_delayed_work_sync(&con->ras_counte_delay_work);
>   
> -	amdgpu_ras_set_context(adev, NULL);
> -	kfree(con);
> +out_free_context:
> +	if (con) {
> +		amdgpu_ras_set_context(adev, NULL);
> +		kfree(con);
> +	}
>   
>   	return 0;
>   }