Re: [PATCH v6 09/10] optee: FF-A: dynamic restricted memory allocation

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

On Wed, Mar 05, 2025 at 02:04:15PM +0100, Jens Wiklander wrote:
> Add support in the OP-TEE backend driver dynamic restricted memory
> allocation with FF-A.
> 
> The restricted memory pools for dynamically allocated restrict memory
> are instantiated when requested by user-space. This instantiation can
> fail if OP-TEE doesn't support the requested use-case of restricted
> memory.
> 
> Restricted memory pools based on a static carveout or dynamic allocation
> can coexist for different use-cases. We use only dynamic allocation with
> FF-A.
> 
> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
> ---
>  drivers/tee/optee/Makefile        |   1 +
>  drivers/tee/optee/ffa_abi.c       | 143 ++++++++++++-
>  drivers/tee/optee/optee_private.h |  13 +-
>  drivers/tee/optee/rstmem.c        | 329 ++++++++++++++++++++++++++++++
>  4 files changed, 483 insertions(+), 3 deletions(-)
>  create mode 100644 drivers/tee/optee/rstmem.c
> 
> diff --git a/drivers/tee/optee/Makefile b/drivers/tee/optee/Makefile
> index a6eff388d300..498969fb8e40 100644
> --- a/drivers/tee/optee/Makefile
> +++ b/drivers/tee/optee/Makefile
> @@ -4,6 +4,7 @@ optee-objs += core.o
>  optee-objs += call.o
>  optee-objs += notif.o
>  optee-objs += rpc.o
> +optee-objs += rstmem.o
>  optee-objs += supp.o
>  optee-objs += device.o
>  optee-objs += smc_abi.o
> diff --git a/drivers/tee/optee/ffa_abi.c b/drivers/tee/optee/ffa_abi.c
> index e4b08cd195f3..6a55114232ef 100644
> --- a/drivers/tee/optee/ffa_abi.c
> +++ b/drivers/tee/optee/ffa_abi.c
> @@ -672,6 +672,123 @@ static int optee_ffa_do_call_with_arg(struct tee_context *ctx,
>  	return optee_ffa_yielding_call(ctx, &data, rpc_arg, system_thread);
>  }
>  
> +static int do_call_lend_rstmem(struct optee *optee, u64 cookie, u32 use_case)
> +{
> +	struct optee_shm_arg_entry *entry;
> +	struct optee_msg_arg *msg_arg;
> +	struct tee_shm *shm;
> +	u_int offs;
> +	int rc;
> +
> +	msg_arg = optee_get_msg_arg(optee->ctx, 1, &entry, &shm, &offs);
> +	if (IS_ERR(msg_arg))
> +		return PTR_ERR(msg_arg);
> +
> +	msg_arg->cmd = OPTEE_MSG_CMD_ASSIGN_RSTMEM;
> +	msg_arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT;
> +	msg_arg->params[0].u.value.a = cookie;
> +	msg_arg->params[0].u.value.b = use_case;
> +
> +	rc = optee->ops->do_call_with_arg(optee->ctx, shm, offs, false);
> +	if (rc)
> +		goto out;
> +	if (msg_arg->ret != TEEC_SUCCESS) {
> +		rc = -EINVAL;
> +		goto out;
> +	}
> +
> +out:
> +	optee_free_msg_arg(optee->ctx, entry, offs);
> +	return rc;
> +}
> +
> +static int optee_ffa_lend_rstmem(struct optee *optee, struct tee_shm *rstmem,
> +				 u16 *end_points, unsigned int ep_count,
> +				 u32 use_case)
> +{
> +	struct ffa_device *ffa_dev = optee->ffa.ffa_dev;
> +	const struct ffa_mem_ops *mem_ops = ffa_dev->ops->mem_ops;
> +	const struct ffa_msg_ops *msg_ops = ffa_dev->ops->msg_ops;
> +	struct ffa_send_direct_data data;
> +	struct ffa_mem_region_attributes *mem_attr;
> +	struct ffa_mem_ops_args args = {
> +		.use_txbuf = true,
> +		.tag = use_case,
> +	};
> +	struct page *page;
> +	struct scatterlist sgl;
> +	unsigned int n;
> +	int rc;
> +
> +	mem_attr = kcalloc(ep_count, sizeof(*mem_attr), GFP_KERNEL);
> +	for (n = 0; n < ep_count; n++) {
> +		mem_attr[n].receiver = end_points[n];
> +		mem_attr[n].attrs = FFA_MEM_RW;
> +	}
> +	args.attrs = mem_attr;
> +	args.nattrs = ep_count;
> +
> +	page = phys_to_page(rstmem->paddr);
> +	sg_init_table(&sgl, 1);
> +	sg_set_page(&sgl, page, rstmem->size, 0);
> +
> +	args.sg = &sgl;
> +	rc = mem_ops->memory_lend(&args);
> +	kfree(mem_attr);
> +	if (rc)
> +		return rc;
> +
> +	rc = do_call_lend_rstmem(optee, args.g_handle, use_case);
> +	if (rc)
> +		goto err_reclaim;
> +
> +	rc = optee_shm_add_ffa_handle(optee, rstmem, args.g_handle);
> +	if (rc)
> +		goto err_unreg;
> +
> +	rstmem->sec_world_id = args.g_handle;
> +
> +	return 0;
> +
> +err_unreg:
> +	data = (struct ffa_send_direct_data){
> +		.data0 = OPTEE_FFA_RELEASE_RSTMEM,
> +		.data1 = (u32)args.g_handle,
> +		.data2 = (u32)(args.g_handle >> 32),
> +	};
> +	msg_ops->sync_send_receive(ffa_dev, &data);
> +err_reclaim:
> +	mem_ops->memory_reclaim(args.g_handle, 0);
> +	return rc;
> +}
> +
> +static int optee_ffa_reclaim_rstmem(struct optee *optee, struct tee_shm *rstmem)
> +{
> +	struct ffa_device *ffa_dev = optee->ffa.ffa_dev;
> +	const struct ffa_msg_ops *msg_ops = ffa_dev->ops->msg_ops;
> +	const struct ffa_mem_ops *mem_ops = ffa_dev->ops->mem_ops;
> +	u64 global_handle = rstmem->sec_world_id;
> +	struct ffa_send_direct_data data = {
> +		.data0 = OPTEE_FFA_RELEASE_RSTMEM,
> +		.data1 = (u32)global_handle,
> +		.data2 = (u32)(global_handle >> 32)
> +	};
> +	int rc;
> +
> +	optee_shm_rem_ffa_handle(optee, global_handle);
> +	rstmem->sec_world_id = 0;
> +
> +	rc = msg_ops->sync_send_receive(ffa_dev, &data);
> +	if (rc)
> +		pr_err("Release SHM id 0x%llx rc %d\n", global_handle, rc);
> +
> +	rc = mem_ops->memory_reclaim(global_handle, 0);
> +	if (rc)
> +		pr_err("mem_reclaim: 0x%llx %d", global_handle, rc);
> +
> +	return rc;
> +}
> +
>  /*
>   * 6. Driver initialization
>   *
> @@ -833,6 +950,8 @@ static const struct optee_ops optee_ffa_ops = {
>  	.do_call_with_arg = optee_ffa_do_call_with_arg,
>  	.to_msg_param = optee_ffa_to_msg_param,
>  	.from_msg_param = optee_ffa_from_msg_param,
> +	.lend_rstmem = optee_ffa_lend_rstmem,
> +	.reclaim_rstmem = optee_ffa_reclaim_rstmem,
>  };
>  
>  static void optee_ffa_remove(struct ffa_device *ffa_dev)
> @@ -941,7 +1060,7 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev)
>  				  optee->pool, optee);
>  	if (IS_ERR(teedev)) {
>  		rc = PTR_ERR(teedev);
> -		goto err_free_pool;
> +		goto err_free_shm_pool;
>  	}
>  	optee->teedev = teedev;
>  
> @@ -988,6 +1107,24 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev)
>  			       rc);
>  	}
>  
> +	if (IS_ENABLED(CONFIG_CMA) && !IS_MODULE(CONFIG_OPTEE) &&

The CMA dependency should be managed via Kconfig.

> +	    (sec_caps & OPTEE_FFA_SEC_CAP_RSTMEM)) {
> +		enum tee_dma_heap_id id = TEE_DMA_HEAP_SECURE_VIDEO_PLAY;
> +		struct tee_rstmem_pool *pool;
> +
> +		pool = optee_rstmem_alloc_cma_pool(optee, id);
> +		if (IS_ERR(pool)) {
> +			rc = PTR_ERR(pool);
> +			goto err_notif_uninit;
> +		}
> +
> +		rc = tee_device_register_dma_heap(optee->teedev, id, pool);
> +		if (rc) {
> +			pool->ops->destroy_pool(pool);
> +			goto err_notif_uninit;
> +		}
> +	}
> +
>  	rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES);
>  	if (rc)
>  		goto err_unregister_devices;
> @@ -1001,6 +1138,8 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev)
>  
>  err_unregister_devices:
>  	optee_unregister_devices();
> +	tee_device_unregister_all_dma_heaps(optee->teedev);
> +err_notif_uninit:
>  	if (optee->ffa.bottom_half_value != U32_MAX)
>  		notif_ops->notify_relinquish(ffa_dev,
>  					     optee->ffa.bottom_half_value);
> @@ -1018,7 +1157,7 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev)
>  	tee_device_unregister(optee->supp_teedev);
>  err_unreg_teedev:
>  	tee_device_unregister(optee->teedev);
> -err_free_pool:
> +err_free_shm_pool:
>  	tee_shm_pool_free(pool);
>  err_free_optee:
>  	kfree(optee);
> diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
> index 20eda508dbac..faab31ad7c52 100644
> --- a/drivers/tee/optee/optee_private.h
> +++ b/drivers/tee/optee/optee_private.h
> @@ -174,9 +174,14 @@ struct optee;
>   * @do_call_with_arg:	enters OP-TEE in secure world
>   * @to_msg_param:	converts from struct tee_param to OPTEE_MSG parameters
>   * @from_msg_param:	converts from OPTEE_MSG parameters to struct tee_param
> + * @lend_rstmem:	lends physically contiguous memory as restricted
> + *			memory, inaccessible by the kernel
> + * @reclaim_rstmem:	reclaims restricted memory previously lent with
> + *			@lend_rstmem() and makes it accessible by the
> + *			kernel again
>   *
>   * These OPs are only supposed to be used internally in the OP-TEE driver
> - * as a way of abstracting the different methogs of entering OP-TEE in
> + * as a way of abstracting the different methods of entering OP-TEE in
>   * secure world.
>   */
>  struct optee_ops {
> @@ -191,6 +196,10 @@ struct optee_ops {
>  			      size_t num_params,
>  			      const struct optee_msg_param *msg_params,
>  			      bool update_out);
> +	int (*lend_rstmem)(struct optee *optee, struct tee_shm *rstmem,
> +			   u16 *end_points, unsigned int ep_count,
> +			   u32 use_case);
> +	int (*reclaim_rstmem)(struct optee *optee, struct tee_shm *rstmem);
>  };
>  
>  /**
> @@ -285,6 +294,8 @@ u32 optee_supp_thrd_req(struct tee_context *ctx, u32 func, size_t num_params,
>  void optee_supp_init(struct optee_supp *supp);
>  void optee_supp_uninit(struct optee_supp *supp);
>  void optee_supp_release(struct optee_supp *supp);
> +struct tee_rstmem_pool *optee_rstmem_alloc_cma_pool(struct optee *optee,
> +						    enum tee_dma_heap_id id);
>  
>  int optee_supp_recv(struct tee_context *ctx, u32 *func, u32 *num_params,
>  		    struct tee_param *param);
> diff --git a/drivers/tee/optee/rstmem.c b/drivers/tee/optee/rstmem.c
> new file mode 100644
> index 000000000000..ea27769934d4
> --- /dev/null
> +++ b/drivers/tee/optee/rstmem.c
> @@ -0,0 +1,329 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) 2025, Linaro Limited
> + */
> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> +
> +#include <linux/errno.h>
> +#include <linux/genalloc.h>
> +#include <linux/slab.h>
> +#include <linux/string.h>
> +#include <linux/tee_core.h>
> +#include <linux/types.h>
> +#include "optee_private.h"
> +
> +struct optee_rstmem_cma_pool {
> +	struct tee_rstmem_pool pool;
> +	struct gen_pool *gen_pool;
> +	struct optee *optee;
> +	size_t page_count;
> +	u16 *end_points;
> +	u_int end_point_count;
> +	u_int align;
> +	refcount_t refcount;
> +	u32 use_case;
> +	struct tee_shm *rstmem;
> +	/* Protects when initializing and tearing down this struct */
> +	struct mutex mutex;
> +};
> +
> +static struct optee_rstmem_cma_pool *
> +to_rstmem_cma_pool(struct tee_rstmem_pool *pool)
> +{
> +	return container_of(pool, struct optee_rstmem_cma_pool, pool);
> +}
> +
> +static int init_cma_rstmem(struct optee_rstmem_cma_pool *rp)
> +{
> +	int rc;
> +
> +	rp->rstmem = tee_shm_alloc_cma_phys_mem(rp->optee->ctx, rp->page_count,
> +						rp->align);
> +	if (IS_ERR(rp->rstmem)) {
> +		rc = PTR_ERR(rp->rstmem);
> +		goto err_null_rstmem;
> +	}
> +
> +	/*
> +	 * TODO unmap the memory range since the physical memory will
> +	 * become inaccesible after the lend_rstmem() call.
> +	 */

What's your plan for this TODO? I think we need a CMA allocator here
which can allocate un-mapped memory such that any cache speculation
won't lead to CPU hangs once the memory restriction comes into picture.

> +	rc = rp->optee->ops->lend_rstmem(rp->optee, rp->rstmem, rp->end_points,
> +					 rp->end_point_count, rp->use_case);
> +	if (rc)
> +		goto err_put_shm;
> +	rp->rstmem->flags |= TEE_SHM_DYNAMIC;
> +
> +	rp->gen_pool = gen_pool_create(PAGE_SHIFT, -1);
> +	if (!rp->gen_pool) {
> +		rc = -ENOMEM;
> +		goto err_reclaim;
> +	}
> +
> +	rc = gen_pool_add(rp->gen_pool, rp->rstmem->paddr,
> +			  rp->rstmem->size, -1);
> +	if (rc)
> +		goto err_free_pool;
> +
> +	refcount_set(&rp->refcount, 1);
> +	return 0;
> +
> +err_free_pool:
> +	gen_pool_destroy(rp->gen_pool);
> +	rp->gen_pool = NULL;
> +err_reclaim:
> +	rp->optee->ops->reclaim_rstmem(rp->optee, rp->rstmem);
> +err_put_shm:
> +	tee_shm_put(rp->rstmem);
> +err_null_rstmem:
> +	rp->rstmem = NULL;
> +	return rc;
> +}
> +
> +static int get_cma_rstmem(struct optee_rstmem_cma_pool *rp)
> +{
> +	int rc = 0;
> +
> +	if (!refcount_inc_not_zero(&rp->refcount)) {
> +		mutex_lock(&rp->mutex);
> +		if (rp->gen_pool) {
> +			/*
> +			 * Another thread has already initialized the pool
> +			 * before us, or the pool was just about to be torn
> +			 * down. Either way we only need to increase the
> +			 * refcount and we're done.
> +			 */
> +			refcount_inc(&rp->refcount);
> +		} else {
> +			rc = init_cma_rstmem(rp);
> +		}
> +		mutex_unlock(&rp->mutex);
> +	}
> +
> +	return rc;
> +}
> +
> +static void release_cma_rstmem(struct optee_rstmem_cma_pool *rp)
> +{
> +	gen_pool_destroy(rp->gen_pool);
> +	rp->gen_pool = NULL;
> +
> +	rp->optee->ops->reclaim_rstmem(rp->optee, rp->rstmem);
> +	rp->rstmem->flags &= ~TEE_SHM_DYNAMIC;
> +
> +	WARN(refcount_read(&rp->rstmem->refcount) != 1, "Unexpected refcount");
> +	tee_shm_put(rp->rstmem);
> +	rp->rstmem = NULL;
> +}
> +
> +static void put_cma_rstmem(struct optee_rstmem_cma_pool *rp)
> +{
> +	if (refcount_dec_and_test(&rp->refcount)) {
> +		mutex_lock(&rp->mutex);
> +		if (rp->gen_pool)
> +			release_cma_rstmem(rp);
> +		mutex_unlock(&rp->mutex);
> +	}
> +}
> +
> +static int rstmem_pool_op_cma_alloc(struct tee_rstmem_pool *pool,
> +				    struct sg_table *sgt, size_t size,
> +				    size_t *offs)
> +{
> +	struct optee_rstmem_cma_pool *rp = to_rstmem_cma_pool(pool);
> +	size_t sz = ALIGN(size, PAGE_SIZE);
> +	phys_addr_t pa;
> +	int rc;
> +
> +	rc = get_cma_rstmem(rp);
> +	if (rc)
> +		return rc;
> +
> +	pa = gen_pool_alloc(rp->gen_pool, sz);
> +	if (!pa) {
> +		rc = -ENOMEM;
> +		goto err_put;
> +	}
> +
> +	rc = sg_alloc_table(sgt, 1, GFP_KERNEL);
> +	if (rc)
> +		goto err_free;
> +
> +	sg_set_page(sgt->sgl, phys_to_page(pa), size, 0);
> +	*offs = pa - rp->rstmem->paddr;
> +
> +	return 0;
> +err_free:
> +	gen_pool_free(rp->gen_pool, pa, size);
> +err_put:
> +	put_cma_rstmem(rp);
> +
> +	return rc;
> +}
> +
> +static void rstmem_pool_op_cma_free(struct tee_rstmem_pool *pool,
> +				    struct sg_table *sgt)
> +{
> +	struct optee_rstmem_cma_pool *rp = to_rstmem_cma_pool(pool);
> +	struct scatterlist *sg;
> +	int i;
> +
> +	for_each_sgtable_sg(sgt, sg, i)
> +		gen_pool_free(rp->gen_pool, sg_phys(sg), sg->length);
> +	sg_free_table(sgt);
> +	put_cma_rstmem(rp);
> +}
> +
> +static int rstmem_pool_op_cma_update_shm(struct tee_rstmem_pool *pool,
> +					 struct sg_table *sgt, size_t offs,
> +					 struct tee_shm *shm,
> +					 struct tee_shm **parent_shm)
> +{
> +	struct optee_rstmem_cma_pool *rp = to_rstmem_cma_pool(pool);
> +
> +	*parent_shm = rp->rstmem;
> +
> +	return 0;
> +}
> +
> +static void pool_op_cma_destroy_pool(struct tee_rstmem_pool *pool)
> +{
> +	struct optee_rstmem_cma_pool *rp = to_rstmem_cma_pool(pool);
> +
> +	mutex_destroy(&rp->mutex);
> +	kfree(rp);
> +}
> +
> +static struct tee_rstmem_pool_ops rstmem_pool_ops_cma = {
> +	.alloc = rstmem_pool_op_cma_alloc,
> +	.free = rstmem_pool_op_cma_free,
> +	.update_shm = rstmem_pool_op_cma_update_shm,
> +	.destroy_pool = pool_op_cma_destroy_pool,
> +};
> +
> +static int get_rstmem_config(struct optee *optee, u32 use_case,
> +			     size_t *min_size, u_int *min_align,
> +			     u16 *end_points, u_int *ep_count)

I guess this end points terminology is specific to FF-A ABI. Is there
any relevance for this in the common APIs?

-Sumit

> +{
> +	struct tee_param params[2] = {
> +		[0] = {
> +			.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT,
> +			.u.value.a = use_case,
> +		},
> +		[1] = {
> +			.attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT,
> +		},
> +	};
> +	struct optee_shm_arg_entry *entry;
> +	struct tee_shm *shm_param = NULL;
> +	struct optee_msg_arg *msg_arg;
> +	struct tee_shm *shm;
> +	u_int offs;
> +	int rc;
> +
> +	if (end_points && *ep_count) {
> +		params[1].u.memref.size = *ep_count * sizeof(*end_points);
> +		shm_param = tee_shm_alloc_priv_buf(optee->ctx,
> +						   params[1].u.memref.size);
> +		if (IS_ERR(shm_param))
> +			return PTR_ERR(shm_param);
> +		params[1].u.memref.shm = shm_param;
> +	}
> +
> +	msg_arg = optee_get_msg_arg(optee->ctx, ARRAY_SIZE(params), &entry,
> +				    &shm, &offs);
> +	if (IS_ERR(msg_arg)) {
> +		rc = PTR_ERR(msg_arg);
> +		goto out_free_shm;
> +	}
> +	msg_arg->cmd = OPTEE_MSG_CMD_GET_RSTMEM_CONFIG;
> +
> +	rc = optee->ops->to_msg_param(optee, msg_arg->params,
> +				      ARRAY_SIZE(params), params,
> +				      false /*!update_out*/);
> +	if (rc)
> +		goto out_free_msg;
> +
> +	rc = optee->ops->do_call_with_arg(optee->ctx, shm, offs, false);
> +	if (rc)
> +		goto out_free_msg;
> +	if (msg_arg->ret && msg_arg->ret != TEEC_ERROR_SHORT_BUFFER) {
> +		rc = -EINVAL;
> +		goto out_free_msg;
> +	}
> +
> +	rc = optee->ops->from_msg_param(optee, params, ARRAY_SIZE(params),
> +					msg_arg->params, true /*update_out*/);
> +	if (rc)
> +		goto out_free_msg;
> +
> +	if (!msg_arg->ret && end_points &&
> +	    *ep_count < params[1].u.memref.size / sizeof(u16)) {
> +		rc = -EINVAL;
> +		goto out_free_msg;
> +	}
> +
> +	*min_size = params[0].u.value.a;
> +	*min_align = params[0].u.value.b;
> +	*ep_count = params[1].u.memref.size / sizeof(u16);
> +
> +	if (msg_arg->ret == TEEC_ERROR_SHORT_BUFFER) {
> +		rc = -ENOSPC;
> +		goto out_free_msg;
> +	}
> +
> +	if (end_points)
> +		memcpy(end_points, tee_shm_get_va(shm_param, 0),
> +		       params[1].u.memref.size);
> +
> +out_free_msg:
> +	optee_free_msg_arg(optee->ctx, entry, offs);
> +out_free_shm:
> +	if (shm_param)
> +		tee_shm_free(shm_param);
> +	return rc;
> +}
> +
> +struct tee_rstmem_pool *optee_rstmem_alloc_cma_pool(struct optee *optee,
> +						    enum tee_dma_heap_id id)
> +{
> +	struct optee_rstmem_cma_pool *rp;
> +	u32 use_case = id;
> +	size_t min_size;
> +	int rc;
> +
> +	rp = kzalloc(sizeof(*rp), GFP_KERNEL);
> +	if (!rp)
> +		return ERR_PTR(-ENOMEM);
> +	rp->use_case = use_case;
> +
> +	rc = get_rstmem_config(optee, use_case, &min_size, &rp->align, NULL,
> +			       &rp->end_point_count);
> +	if (rc) {
> +		if (rc != -ENOSPC)
> +			goto err;
> +		rp->end_points = kcalloc(rp->end_point_count,
> +					 sizeof(*rp->end_points), GFP_KERNEL);
> +		if (!rp->end_points) {
> +			rc = -ENOMEM;
> +			goto err;
> +		}
> +		rc = get_rstmem_config(optee, use_case, &min_size, &rp->align,
> +				       rp->end_points, &rp->end_point_count);
> +		if (rc)
> +			goto err_kfree_eps;
> +	}
> +
> +	rp->pool.ops = &rstmem_pool_ops_cma;
> +	rp->optee = optee;
> +	rp->page_count = min_size / PAGE_SIZE;
> +	mutex_init(&rp->mutex);
> +
> +	return &rp->pool;
> +
> +err_kfree_eps:
> +	kfree(rp->end_points);
> +err:
> +	kfree(rp);
> +	return ERR_PTR(rc);
> +}
> -- 
> 2.43.0
>