On Wed, Feb 05, 2025 at 04:17:21PM -0700, Alex Williamson wrote: > @@ -590,15 +592,23 @@ static int vaddr_get_pfns(struct mm_struct *mm, unsigned long vaddr, > vma = vma_lookup(mm, vaddr); > > if (vma && vma->vm_flags & VM_PFNMAP) { > - ret = follow_fault_pfn(vma, mm, vaddr, pfn, prot & IOMMU_WRITE); > + unsigned long pgmask; > + > + ret = follow_fault_pfn(vma, mm, vaddr, pfn, &pgmask, > + prot & IOMMU_WRITE); > if (ret == -EAGAIN) > goto retry; > > if (!ret) { > - if (is_invalid_reserved_pfn(*pfn)) > - ret = 1; > - else > + if (is_invalid_reserved_pfn(*pfn)) { > + unsigned long epfn; > + > + epfn = (((*pfn << PAGE_SHIFT) + ~pgmask + 1) > + & pgmask) >> PAGE_SHIFT; That seems a bit indirect epfn = ((*pfn) | (~pgmask >> PAGE_SHIFT)) + 1; ? > + ret = min_t(int, npages, epfn - *pfn); It is nitty but the int's here should be long, and npages should be unsigned long.. Jason