Commit 7b8aa998 authored by Lu Baolu's avatar Lu Baolu Committed by Joerg Roedel
Browse files

iommu/vt-d: Remove unnecessary checks in iopf disabling path 



iommu_unregister_device_fault_handler() and iopf_queue_remove_device()
are called after device has stopped issuing new page falut requests and
all outstanding page requests have been drained. They should never fail.
Trigger a warning if it happens unfortunately.

Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20230324120234.313643-7-baolu.lu@linux.intel.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent fbcde5bb

drivers/iommu/intel/iommu.c

+8 −9
Original line number Diff line number Diff line
@@ -4707,7 +4707,6 @@ static int intel_iommu_disable_iopf(struct device *dev) 
{

	struct device_domain_info *info = dev_iommu_priv_get(dev);

	struct intel_iommu *iommu = info->iommu;

	int ret;



	if (!info->pri_enabled)

		return -EINVAL;
@@ -4723,15 +4722,15 @@ static int intel_iommu_disable_iopf(struct device *dev) 
	pci_disable_pri(to_pci_dev(dev));

	info->pri_enabled = 0;



	ret = iommu_unregister_device_fault_handler(dev);

	if (ret)

		return ret;



	ret = iopf_queue_remove_device(iommu->iopf_queue, dev);

	if (ret)

		iommu_register_device_fault_handler(dev, iommu_queue_iopf, dev);

	/*

	 * With PRI disabled and outstanding PRQs drained, unregistering

	 * fault handler and removing device from iopf queue should never

	 * fail.

	 */

	WARN_ON(iommu_unregister_device_fault_handler(dev));

	WARN_ON(iopf_queue_remove_device(iommu->iopf_queue, dev));



	return ret;

	return 0;

}



static int