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Commit e0230e13 authored by Yang Zhang's avatar Yang Zhang Committed by Paolo Bonzini
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KVM: Mapping IOMMU pages after updating memslot 



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: default avatarYang Zhang <yang.z.zhang@Intel.com>
Tested-by: default avatarPatrick Lu <patrick.lu@intel.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent a294c9bb

virt/kvm/kvm_main.c

+14 −15
Original line number Diff line number Diff line
@@ -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: