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

Will Deacon
2022-11-21T18:06:57Z

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@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