From 24cd19a28cb7174df502162641d6e1e12e7ffbd9 Mon Sep 17 00:00:00 2001 From: Lai Jiangshan Date: Thu, 11 Nov 2021 22:45:26 +0800 Subject: [PATCH] KVM: X86: Update mmu->pdptrs only when it is changed It is unchanged in most cases. Signed-off-by: Lai Jiangshan Message-Id: <20211111144527.88852-1-jiangshanlai@gmail.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index be3b4a0..d4f1dff 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -828,9 +828,12 @@ int load_pdptrs(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu, unsigned long cr3) } } - memcpy(mmu->pdptrs, pdpte, sizeof(mmu->pdptrs)); - kvm_register_mark_dirty(vcpu, VCPU_EXREG_PDPTR); - kvm_make_request(KVM_REQ_LOAD_MMU_PGD, vcpu); + kvm_register_mark_available(vcpu, VCPU_EXREG_PDPTR); + if (memcmp(mmu->pdptrs, pdpte, sizeof(mmu->pdptrs))) { + memcpy(mmu->pdptrs, pdpte, sizeof(mmu->pdptrs)); + kvm_register_mark_dirty(vcpu, VCPU_EXREG_PDPTR); + kvm_make_request(KVM_REQ_LOAD_MMU_PGD, vcpu); + } vcpu->arch.pdptrs_from_userspace = false; return 1; -- 2.7.4