Il 24/10/2013 03:56, Yang Zhang ha scritto:
> From: Yang Zhang <yang.z.zhang@xxxxxxxxx>
>
> In kvm_iommu_map_pages(), we need to know the page size via call
> kvm_host_page_size(). And it will check whether the target slot
> is valid before return the right page size.
> Currently, we will map the iommu pages when creating a new slot.
> But we call kvm_iommu_map_pages() during preparing the new slot.
> At that time, the new slot is not visible by domain(still in preparing).
> So we cannot get the right page size from kvm_host_page_size() and
> this will break the IOMMU super page logic.
> The solution is to map the iommu pages after we insert the new slot
> into domain.
>
> Signed-off-by: Yang Zhang <yang.z.zhang@xxxxxxxxx>
> Tested-by: Patrick Lu <patrick.lu@xxxxxxxxx>
> ---
> virt/kvm/kvm_main.c | 29 ++++++++++++++---------------
> 1 files changed, 14 insertions(+), 15 deletions(-)
>
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index d469114..9ec60a2 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -873,21 +873,6 @@ int __kvm_set_memory_region(struct kvm *kvm,
> goto out_free;
> }
>
> - /*
> - * IOMMU mapping: New slots need to be mapped. Old slots need to be
> - * un-mapped and re-mapped if their base changes. Since base change
> - * unmapping is handled above with slot deletion, mapping alone is
> - * needed here. Anything else the iommu might care about for existing
> - * slots (size changes, userspace addr changes and read-only flag
> - * changes) is disallowed above, so any other attribute changes getting
> - * here can be skipped.
> - */
> - if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
> - r = kvm_iommu_map_pages(kvm, &new);
> - if (r)
> - goto out_slots;
> - }
> -
> /* actual memory is freed via old in kvm_free_physmem_slot below */
> if (change == KVM_MR_DELETE) {
> new.dirty_bitmap = NULL;
> @@ -901,6 +886,20 @@ int __kvm_set_memory_region(struct kvm *kvm,
> kvm_free_physmem_slot(&old, &new);
> kfree(old_memslots);
>
> + /*
> + * IOMMU mapping: New slots need to be mapped. Old slots need to be
> + * un-mapped and re-mapped if their base changes. Since base change
> + * unmapping is handled above with slot deletion, mapping alone is
> + * needed here. Anything else the iommu might care about for existing
> + * slots (size changes, userspace addr changes and read-only flag
> + * changes) is disallowed above, so any other attribute changes getting
> + * here can be skipped.
> + */
> + if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
> + r = kvm_iommu_map_pages(kvm, &new);
> + return r;
> + }
> +
> return 0;
>
> out_slots:
>
Applied to kvm.git queue, thanks.
Paolo
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
