[PATCH v2 2/5] KVM MMU: fix kvm_mmu_zap_page() and its calling path

[Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>]

- calculate zapped page number properly in mmu_zap_unsync_children()
- calculate freeed page number properly kvm_mmu_change_mmu_pages()

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
---
 arch/x86/kvm/mmu.c |   12 ++++++++----
 1 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index a23ca75..41cccd4 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1481,13 +1481,16 @@ static int mmu_zap_unsync_children(struct kvm *kvm,
 		struct kvm_mmu_page *sp;
 
 		for_each_sp(pages, sp, parents, i) {
+			if (list_empty(&kvm->arch.active_mmu_pages))
+				goto exit;
+
 			kvm_mmu_zap_page(kvm, sp);
 			mmu_pages_clear_parents(&parents);
+			zapped++;
 		}
-		zapped += pages.nr;
 		kvm_mmu_pages_init(parent, &parents, &pages);
 	}
-
+exit:
 	return zapped;
 }
 
@@ -1540,7 +1543,7 @@ void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages)
 
 			page = container_of(kvm->arch.active_mmu_pages.prev,
 					    struct kvm_mmu_page, link);
-			kvm_mmu_zap_page(kvm, page);
+			used_pages -= kvm_mmu_zap_page(kvm, page);
 			used_pages--;
 		}
 		kvm->arch.n_free_mmu_pages = 0;
@@ -1589,7 +1592,8 @@ static void mmu_unshadow(struct kvm *kvm, gfn_t gfn)
 		    && !sp->role.invalid) {
 			pgprintk("%s: zap %lx %x\n",
 				 __func__, gfn, sp->role.word);
-			kvm_mmu_zap_page(kvm, sp);
+			if (kvm_mmu_zap_page(kvm, sp))
+				nn = bucket->first;
 		}
 	}
 }
-- 
1.6.1.2