From e0230e1327fb862c9b6cde24ae62d55f9db62c9b Mon Sep 17 00:00:00 2001 From: Yang Zhang Date: Thu, 24 Oct 2013 09:56:39 +0800 Subject: [PATCH] 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: Yang Zhang Tested-by: Patrick Lu Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 0d20c320a33d..9ca014da134d 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: -- 2.39.5