From 960c9d696b30cfed659cd56d4c7f1bfac7d9c424 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Mon, 10 Dec 2012 10:32:57 -0700 Subject: [PATCH] KVM: Fix iommu map/unmap to handle memory slot moves commit e40f193f5bb022e927a57a4f5d5194e4f12ddb74 upstream. The iommu integration into memory slots expects memory slots to be added or removed and doesn't handle the move case. We can unmap slots from the iommu after we mark them invalid and map them before installing the final memslot array. Also re-order the kmemdup vs map so we don't leave iommu mappings if we get ENOMEM. Reviewed-by: Gleb Natapov Signed-off-by: Alex Williamson Signed-off-by: Marcelo Tosatti [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- virt/kvm/kvm_main.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a31166097dc3..d83aa5e700d5 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -788,6 +788,8 @@ skip_lpage: old_memslots = kvm->memslots; rcu_assign_pointer(kvm->memslots, slots); synchronize_srcu_expedited(&kvm->srcu); + /* slot was deleted or moved, clear iommu mapping */ + kvm_iommu_unmap_pages(kvm, &old); /* From this point no new shadow pages pointing to a deleted, * or moved, memslot will be created. * @@ -803,14 +805,6 @@ skip_lpage: if (r) goto out_free; - /* map/unmap the pages in iommu page table */ - if (npages) { - r = kvm_iommu_map_pages(kvm, &new); - if (r) - goto out_free; - } else - kvm_iommu_unmap_pages(kvm, &old); - r = -ENOMEM; slots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL); if (!slots) @@ -820,6 +814,13 @@ skip_lpage: slots->nmemslots = mem->slot + 1; slots->generation++; + /* map new memory slot into the iommu */ + if (npages) { + 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 (!npages) { new.rmap = NULL; @@ -847,6 +848,8 @@ skip_lpage: return 0; +out_slots: + kfree(slots); out_free: kvm_free_physmem_slot(&new, &old); out: -- 2.39.2