Re: [PATCH 2/2] accel/amdxdna: fix error code being silently swallowed in hwctx status queries

[Lizhi Hou <lizhi.hou@amd.com>]

On 6/2/26 18:35, Jackie Liu wrote:
> From: Jackie Liu <liuyun01@kylinos.cn>
>
> Both aie2_get_hwctx_status() and aie2_query_ctx_status_array() iterate
> over hardware contexts calling amdxdna_hwctx_walk() with a callback
> that can fail with -ENOMEM (allocation failure) or -EFAULT
> (copy_to_user failure). When the walk fails, the loop correctly breaks
> but the functions always return 0 to userspace, swallowing the error.
>
> This means userspace receives no indication that the data may be
> incomplete or that the operation failed. Save the error code and
> return it to properly propagate failures to userspace.
>
> Fixes: 81233d5419cf ("accel/amdxdna: Fix uninitialized return value")

The retrieving information can be partially done. The amount of valid 
results is indicated by the returned buffer_size, element_size, and 
num_element fields. Thus, 0 is returned. So user space will not consider 
this is a broken error and still get the partial results.

Lizhi

> Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
> ---
>   drivers/accel/amdxdna/aie2_pci.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/accel/amdxdna/aie2_pci.c b/drivers/accel/amdxdna/aie2_pci.c
> index 4500b9ccb02e..0ff87fafd049 100644
> --- a/drivers/accel/amdxdna/aie2_pci.c
> +++ b/drivers/accel/amdxdna/aie2_pci.c
> @@ -908,7 +908,7 @@ static int aie2_get_hwctx_status(struct amdxdna_client *client,
>   	struct amdxdna_drm_get_array array_args;
>   	struct amdxdna_dev *xdna = client->xdna;
>   	struct amdxdna_client *tmp_client;
> -	int ret;
> +	int ret = 0;
>   
>   	drm_WARN_ON(&xdna->ddev, !mutex_is_locked(&xdna->dev_lock));
>   
> @@ -923,7 +923,7 @@ static int aie2_get_hwctx_status(struct amdxdna_client *client,
>   	}
>   
>   	args->buffer_size -= (u32)(array_args.buffer - args->buffer);
> -	return 0;
> +	return ret;
>   }
>   
>   static int aie2_query_resource_info(struct amdxdna_client *client,
> @@ -1105,7 +1105,7 @@ static int aie2_query_ctx_status_array(struct amdxdna_client *client,
>   	struct amdxdna_drm_get_array array_args;
>   	struct amdxdna_dev *xdna = client->xdna;
>   	struct amdxdna_client *tmp_client;
> -	int ret;
> +	int ret = 0;
>   
>   	drm_WARN_ON(&xdna->ddev, !mutex_is_locked(&xdna->dev_lock));
>   
> @@ -1131,7 +1131,7 @@ static int aie2_query_ctx_status_array(struct amdxdna_client *client,
>   	args->num_element = (u32)((array_args.buffer - args->buffer) /
>   				  args->element_size);
>   
> -	return 0;
> +	return ret;
>   }
>   
>   static int aie2_get_array(struct amdxdna_client *client,