[PATCH v2] KVM: x86/mmu: Check every prev_roots in __kvm_mmu_free_obsolete_roots()

[shaoqin . huang]

From: Shaoqin Huang <shaoqin.huang@xxxxxxxxx>

When freeing obsolete previous roots, check prev_roots as intended, not
the current root.

Signed-off-by: Shaoqin Huang <shaoqin.huang@xxxxxxxxx>
Fixes: 527d5cd7eece ("KVM: x86/mmu: Zap only obsolete roots if a root shadow page is zapped")
---
Changes in v2:
  - Make the commit message more clearer.
  - Fixed the missing idx.

 arch/x86/kvm/mmu/mmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index f4653688fa6d..e826ee9138fa 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -5179,7 +5179,7 @@ static void __kvm_mmu_free_obsolete_roots(struct kvm *kvm, struct kvm_mmu *mmu)
 		roots_to_free |= KVM_MMU_ROOT_CURRENT;
 
 	for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) {
-		if (is_obsolete_root(kvm, mmu->root.hpa))
+		if (is_obsolete_root(kvm, mmu->prev_roots[i].hpa))
 			roots_to_free |= KVM_MMU_ROOT_PREVIOUS(i);
 	}
 
-- 
2.30.2