driver should implement both set_dev_pasid and remove_dev_pasid op, otherwise it is a problem how to detach pasid. In reality, it is impossible that an iommu driver implements set_dev_pasid() but no remove_dev_pasid() op. However, it is better to check it. Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx> Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx> --- drivers/iommu/iommu.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 13fcd9d8f2df..1c689e57928e 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -3352,17 +3352,19 @@ int iommu_attach_device_pasid(struct iommu_domain *domain, struct iommu_attach_handle *handle) { /* Caller must be a probed driver on dev */ + const struct iommu_ops *ops = dev_iommu_ops(dev); struct iommu_group *group = dev->iommu_group; struct group_device *device; int ret; - if (!domain->ops->set_dev_pasid) + if (!domain->ops->set_dev_pasid || + !ops->remove_dev_pasid) return -EOPNOTSUPP; if (!group) return -ENODEV; - if (!dev_has_iommu(dev) || dev_iommu_ops(dev) != domain->owner || + if (!dev_has_iommu(dev) || ops != domain->owner || pasid == IOMMU_NO_PASID) return -EINVAL; -- 2.34.1