Re: [PATCH 1/3] tee: qcomtee: call: Fix confusing cleanup.h syntax

[Sumit Garg <sumit.garg@kernel.org>]

On Mon, Dec 08, 2025 at 03:08:45AM +0100, Krzysztof Kozlowski wrote:
> Initializing automatic __free variables to NULL without need (e.g.
> branches with different allocations), followed by actual allocation is
> in contrary to explicit coding rules guiding cleanup.h:
> 
> "Given that the "__free(...) = NULL" pattern for variables defined at
> the top of the function poses this potential interdependency problem the
> recommendation is to always define and assign variables in one statement
> and not group variable definitions at the top of the function when
> __free() is used."
> 
> Code does not have a bug, but is less readable and uses discouraged
> coding practice, so fix that by moving declaration to the place of
> assignment.

Okay I see but..

> 
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
> ---
>  drivers/tee/qcomtee/call.c | 17 ++++++++---------
>  1 file changed, 8 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/tee/qcomtee/call.c b/drivers/tee/qcomtee/call.c
> index 65f9140d4e1f..8f8830f0df26 100644
> --- a/drivers/tee/qcomtee/call.c
> +++ b/drivers/tee/qcomtee/call.c
> @@ -395,9 +395,7 @@ static int qcomtee_object_invoke(struct tee_context *ctx,
>  				 struct tee_ioctl_object_invoke_arg *arg,
>  				 struct tee_param *params)
>  {
> -	struct qcomtee_object_invoke_ctx *oic __free(kfree) = NULL;
>  	struct qcomtee_context_data *ctxdata = ctx->data;
> -	struct qcomtee_arg *u __free(kfree) = NULL;
>  	struct qcomtee_object *object;
>  	int i, ret, result;
>  
> @@ -412,12 +410,14 @@ static int qcomtee_object_invoke(struct tee_context *ctx,
>  	}
>  
>  	/* Otherwise, invoke a QTEE object: */
> -	oic = qcomtee_object_invoke_ctx_alloc(ctx);
> +	struct qcomtee_object_invoke_ctx *oic __free(kfree) =
> +		qcomtee_object_invoke_ctx_alloc(ctx);
>  	if (!oic)
>  		return -ENOMEM;
>  
>  	/* +1 for ending QCOMTEE_ARG_TYPE_INV. */
> -	u = kcalloc(arg->num_params + 1, sizeof(*u), GFP_KERNEL);
> +	struct qcomtee_arg *u __free(kfree) = kcalloc(arg->num_params + 1, sizeof(*u),
> +						      GFP_KERNEL);

..this makes the code less readable with variable declarations floating
within the function. I would rather favor to not use the cleanup.h construct
but use explicit kfree() invocations instead like it's done in all other
allocations in the TEE subsystem.

-Sumit

>  	if (!u)
>  		return -ENOMEM;
>  
> @@ -562,9 +562,8 @@ static int qcomtee_supp_send(struct tee_context *ctx, u32 errno, u32 num_params,
>  
>  static int qcomtee_open(struct tee_context *ctx)
>  {
> -	struct qcomtee_context_data *ctxdata __free(kfree) = NULL;
> -
> -	ctxdata = kzalloc(sizeof(*ctxdata), GFP_KERNEL);
> +	struct qcomtee_context_data *ctxdata __free(kfree) = kzalloc(sizeof(*ctxdata),
> +								     GFP_KERNEL);
>  	if (!ctxdata)
>  		return -ENOMEM;
>  
> @@ -645,12 +644,12 @@ static void qcomtee_get_version(struct tee_device *teedev,
>  static void qcomtee_get_qtee_feature_list(struct tee_context *ctx, u32 id,
>  					  u32 *version)
>  {
> -	struct qcomtee_object_invoke_ctx *oic __free(kfree) = NULL;
>  	struct qcomtee_object *client_env, *service;
>  	struct qcomtee_arg u[3] = { 0 };
>  	int result;
>  
> -	oic = qcomtee_object_invoke_ctx_alloc(ctx);
> +	struct qcomtee_object_invoke_ctx *oic __free(kfree) =
> +		qcomtee_object_invoke_ctx_alloc(ctx);
>  	if (!oic)
>  		return;
>  
> -- 
> 2.51.0
>