KVM: unmap SMM memslots in vt-d table

[Qemu-devel] [PATCH] KVM: unmap SMM memslots in vt-d table

Posted by herongguang 7 years ago

or pages are not unmaped and freed

Signed-off-by: herongguang <herongguang.he@huawei.com>
---
 arch/x86/kvm/iommu.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

Well, do we should change pci-assign to not map SMM slots instead? Like vfio.
 
diff --git a/arch/x86/kvm/iommu.c b/arch/x86/kvm/iommu.c
index b181426..5b931bb 100644
--- a/arch/x86/kvm/iommu.c
+++ b/arch/x86/kvm/iommu.c
@@ -320,15 +320,17 @@ void kvm_iommu_unmap_pages(struct kvm *kvm, struct kvm_memory_slot *slot)
 static int kvm_iommu_unmap_memslots(struct kvm *kvm)
 {
 	int idx;
-	struct kvm_memslots *slots;
+	struct kvm_memslots *slots, *smm_slots;
 	struct kvm_memory_slot *memslot;
 
 	idx = srcu_read_lock(&kvm->srcu);
 	slots = kvm_memslots(kvm);
-
 	kvm_for_each_memslot(memslot, slots)
 		kvm_iommu_unmap_pages(kvm, memslot);
 
+	smm_slots = __kvm_memslots(kvm, 1);
+	kvm_for_each_memslot(memslot, smm_slots)
+		kvm_iommu_unmap_pages(kvm, memslot);
 	srcu_read_unlock(&kvm->srcu, idx);
 
 	if (kvm->arch.iommu_noncoherent)
-- 
1.7.12.4

[Qemu-devel] [PATCH v2] KVM: pci-assign: do not map smm memory slot pages

Posted by Herongguang (Stephen) 7 years ago

 From f6f0ee6831488bef7af841cb86f3d85a04848fe5 Mon Sep 17 00:00:00 2001
From: herongguang <herongguang.he@huawei.com>
Date: Mon, 27 Mar 2017 15:08:59 +0800
Subject: [PATCH] KVM: pci-assign: do not map smm memory slot pages
  in vt-d page table

or VM memory are not put thus leaked in kvm_iommu_unmap_memslots() when
destroy VM.

This is consistent with current vfio implementation.
---
  virt/kvm/kvm_main.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 482612b..9018d06 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1052,7 +1052,7 @@ int __kvm_set_memory_region(struct kvm *kvm,
  	 * changes) is disallowed above, so any other attribute changes getting
  	 * here can be skipped.
  	 */
-	if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
+	if ((as_id == 0) && ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE))) {
  		r = kvm_iommu_map_pages(kvm, &new);
  		return r;
  	}
-- 
1.7.12.4

On 2017/3/25 19:14, herongguang wrote:
> or pages are not unmaped and freed
>
> Signed-off-by: herongguang <herongguang.he@huawei.com>
> ---
>   arch/x86/kvm/iommu.c | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)
>
> Well, do we should change pci-assign to not map SMM slots instead? Like vfio.
>
> diff --git a/arch/x86/kvm/iommu.c b/arch/x86/kvm/iommu.c
> index b181426..5b931bb 100644
> --- a/arch/x86/kvm/iommu.c
> +++ b/arch/x86/kvm/iommu.c
> @@ -320,15 +320,17 @@ void kvm_iommu_unmap_pages(struct kvm *kvm, struct kvm_memory_slot *slot)
>   static int kvm_iommu_unmap_memslots(struct kvm *kvm)
>   {
>   	int idx;
> -	struct kvm_memslots *slots;
> +	struct kvm_memslots *slots, *smm_slots;
>   	struct kvm_memory_slot *memslot;
>
>   	idx = srcu_read_lock(&kvm->srcu);
>   	slots = kvm_memslots(kvm);
> -
>   	kvm_for_each_memslot(memslot, slots)
>   		kvm_iommu_unmap_pages(kvm, memslot);
>
> +	smm_slots = __kvm_memslots(kvm, 1);
> +	kvm_for_each_memslot(memslot, smm_slots)
> +		kvm_iommu_unmap_pages(kvm, memslot);
>   	srcu_read_unlock(&kvm->srcu, idx);
>
>   	if (kvm->arch.iommu_noncoherent)
>