[PATCH v2] iommu: fix smmu initialization memory leak problem

[Will Deacon]

On Mon, Nov 21, 2022 at 11:04:21AM +0800, Longfang Liu wrote:
> When iommu_device_register() in arm_smmu_device_probe() fails,
> in addition to sysfs needs to be deleted, device should also
> be disabled, and the memory of iopf needs to be released to
> prevent memory leak of iopf.
> 
> Changes v1 -> v2:
> 	-Improve arm_smmu_device_probe() abnormal exit function.
> 
> Signed-off-by: Longfang Liu <liulongfang at huawei.com>
> ---
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 16 +++++++++++-----
>  1 file changed, 11 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> index ab160198edd6..b892f5233f88 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -3815,7 +3815,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
>  	/* Initialise in-memory data structures */
>  	ret = arm_smmu_init_structures(smmu);
>  	if (ret)
> -		return ret;
> +		goto err_iopf;
>  
>  	/* Record our private device structure */
>  	platform_set_drvdata(pdev, smmu);
> @@ -3826,22 +3826,28 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
>  	/* Reset the device */
>  	ret = arm_smmu_device_reset(smmu, bypass);
>  	if (ret)
> -		return ret;
> +		goto err_iopf;
>  
>  	/* And we're up. Go go go! */
>  	ret = iommu_device_sysfs_add(&smmu->iommu, dev, NULL,
>  				     "smmu3.%pa", &ioaddr);
>  	if (ret)
> -		return ret;
> +		goto err_reset;
>  
>  	ret = iommu_device_register(&smmu->iommu, &arm_smmu_ops, dev);
>  	if (ret) {
>  		dev_err(dev, "Failed to register iommu\n");
> -		iommu_device_sysfs_remove(&smmu->iommu);
> -		return ret;
> +		goto err_sysfs_add;
>  	}
>  
>  	return 0;
> +err_sysfs_add:
> +	iommu_device_sysfs_remove(&smmu->iommu);
> +err_reset:
> +	arm_smmu_device_disable(smmu);
> +err_iopf:
> +	iopf_queue_free(smmu->evtq.iopf);
> +	return ret;

I previously suggested using devres_alloc() for this instead. Did that
not work?

Will