On Tue, Jul 12, 2022 at 10:21:14AM -0400, Anthony Krowiak wrote: > > +void vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn, > > + int npage) > > { > > struct vfio_container *container; > > struct vfio_iommu_driver *driver; > > - int ret; > > > > - if (!user_pfn || !npage || !vfio_assert_device_open(device)) > > - return -EINVAL; > > > You left out the check for !user_pfn? Yes. I mentioned in the commit log. And it's in response to Jason's remark: https://lore.kernel.org/kvm/20220707192210.GC1705032@xxxxxxxxxx/ Btw, user_pfn is removed in one of the following patches anyway. > > +static void vfio_iommu_type1_unpin_pages(void *iommu_data, > > + unsigned long *user_pfn, int npage) > > { > > struct vfio_iommu *iommu = iommu_data; > > bool do_accounting; > > int i; > > > > - if (!iommu || !user_pfn || npage <= 0) > > - return -EINVAL; > > > Is there a reason the checks above were not checked for WARN_ON? For pointers, same reason here. For npage, it's checked in its caller vfio_unpin_pages -- mentioned in the commit log too. The VFIO core is the only caller and it is unlikely to change. On the other hand, the plan is to replace this vfio_iommu_type1_unpin_pages with IOMMUFD implementation.