Re: [PATCH v5 13/23] iommu: introduce device fault report API
From: Jean-Philippe Brucker
Date: Tue Sep 25 2018 - 10:59:04 EST
Hi Jacob,
Just two minor things below, that I noticed while using fault handlers
for SVA. From my perspective the series is fine otherwise
On 11/05/2018 21:54, Jacob Pan wrote:
> +int iommu_unregister_device_fault_handler(struct device *dev)
> +{
> + struct iommu_param *param = dev->iommu_param;
> + int ret = 0;
> +
> + if (!param)
> + return -EINVAL;
> +
> + mutex_lock(¶m->lock);
Could we check that param->fault_param isn't NULL here, so that the
driver can call this function unconditionally in a cleanup path?
> + /* we cannot unregister handler if there are pending faults */
> + if (!list_empty(¶m->fault_param->faults)) {
> + ret = -EBUSY;
> + goto unlock;
> + }
> +
> + kfree(param->fault_param);
> + param->fault_param = NULL;
> + put_device(dev);
> +unlock:
> + mutex_unlock(¶m->lock);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(iommu_unregister_device_fault_handler);
> +
> +
> +/**
> + * iommu_report_device_fault() - Report fault event to device
> + * @dev: the device
> + * @evt: fault event data
> + *
> + * Called by IOMMU model specific drivers when fault is detected, typically
> + * in a threaded IRQ handler.
> + *
> + * Return 0 on success, or an error.
> + */
> +int iommu_report_device_fault(struct device *dev, struct
> iommu_fault_event *evt)
> +{
> + int ret = 0;
> + struct iommu_fault_event *evt_pending;
> + struct iommu_fault_param *fparam;
> +
> + /* iommu_param is allocated when device is added to group */
> + if (!dev->iommu_param | !evt)
Should probably be ||
Thanks,
Jean