On Wed, Sep 20, 2023 at 01:28:41PM +0800, Baolu Lu wrote: > > > > diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c > > index 5db283c17e0d..491bcde1ff96 100644 > > --- a/drivers/iommu/intel/iommu.c > > +++ b/drivers/iommu/intel/iommu.c > > @@ -4074,6 +4074,25 @@ static struct iommu_domain *intel_iommu_domain_alloc(unsigned type) > > return NULL; > > } > > +static struct iommu_domain * > > +intel_iommu_domain_alloc_user(struct device *dev, u32 flags) > > +{ > > + struct iommu_domain *domain; > > + struct intel_iommu *iommu; > > + > > + iommu = device_to_iommu(dev, NULL, NULL); > > + if (!iommu) > > + return ERR_PTR(-ENODEV); > > + > > + if ((flags & IOMMU_HWPT_ALLOC_NEST_PARENT) && !ecap_nest(iommu->ecap)) > > + return ERR_PTR(-EOPNOTSUPP); There is a check missing for supported flags if (flags & (~IOMMU_HWPT_ALLOC_NEST_PARENT)) return ERR_PTR(-EOPNOTSUPP); > > + > > + domain = iommu_domain_alloc(dev->bus); > > No need to bounce between core and driver. Just, > > intel_iommu_domain_alloc(IOMMU_DOMAIN_UNMANAGED); > > and fully initialize it before return. If you are going to do that then intel_iommu_domain_alloc() should fully initialize the domain, not here. Jason