On Fri, Jul 17, 2020 at 01:00:26AM -0700, Ram Pai wrote:
> @@ -812,7 +842,7 @@ unsigned long kvmppc_h_svm_page_in(struct kvm *kvm, unsigned long gpa,
> struct vm_area_struct *vma;
> int srcu_idx;
> unsigned long gfn = gpa >> page_shift;
> - int ret;
> + int ret, repeat_count = REPEAT_COUNT;
>
> if (!(kvm->arch.secure_guest & KVMPPC_SECURE_INIT_START))
> return H_UNSUPPORTED;
> @@ -826,34 +856,44 @@ unsigned long kvmppc_h_svm_page_in(struct kvm *kvm, unsigned long gpa,
> if (flags & H_PAGE_IN_SHARED)
> return kvmppc_share_page(kvm, gpa, page_shift);
>
> - ret = H_PARAMETER;
> srcu_idx = srcu_read_lock(&kvm->srcu);
> - mmap_read_lock(kvm->mm);
>
> - start = gfn_to_hva(kvm, gfn);
> - if (kvm_is_error_hva(start))
> - goto out;
> -
> - mutex_lock(&kvm->arch.uvmem_lock);
> /* Fail the page-in request of an already paged-in page */
> - if (kvmppc_gfn_is_uvmem_pfn(gfn, kvm, NULL))
> - goto out_unlock;
> + mutex_lock(&kvm->arch.uvmem_lock);
> + ret = kvmppc_gfn_is_uvmem_pfn(gfn, kvm, NULL);
> + mutex_unlock(&kvm->arch.uvmem_lock);
Same comment as for the prev patch. I don't think you can release
the lock here.
> + if (ret) {
> + srcu_read_unlock(&kvm->srcu, srcu_idx);
> + return H_PARAMETER;
> + }
>
> - end = start + (1UL << page_shift);
> - vma = find_vma_intersection(kvm->mm, start, end);
> - if (!vma || vma->vm_start > start || vma->vm_end < end)
> - goto out_unlock;
> + do {
> + ret = H_PARAMETER;
> + mmap_read_lock(kvm->mm);
>
> - if (kvmppc_svm_migrate_page(vma, start, end, gpa, kvm, page_shift,
> - true))
> - goto out_unlock;
> + start = gfn_to_hva(kvm, gfn);
> + if (kvm_is_error_hva(start)) {
> + mmap_read_unlock(kvm->mm);
> + break;
> + }
>
> - ret = H_SUCCESS;
> + end = start + (1UL << page_shift);
> + vma = find_vma_intersection(kvm->mm, start, end);
> + if (!vma || vma->vm_start > start || vma->vm_end < end) {
> + mmap_read_unlock(kvm->mm);
> + break;
> + }
> +
> + mutex_lock(&kvm->arch.uvmem_lock);
> + ret = kvmppc_svm_migrate_page(vma, start, end, gpa, kvm, page_shift, true);
> + mutex_unlock(&kvm->arch.uvmem_lock);
> +
> + mmap_read_unlock(kvm->mm);
> + } while (ret == -2 && repeat_count--);
> +
> + if (ret == -2)
> + ret = H_BUSY;
>
> -out_unlock:
> - mutex_unlock(&kvm->arch.uvmem_lock);
> -out:
> - mmap_read_unlock(kvm->mm);
> srcu_read_unlock(&kvm->srcu, srcu_idx);
> return ret;
> }
> --
> 1.8.3.1
