On Tue, Jun 12, 2018 at 03:52:36PM -0700, Junaid Shahid wrote:
> Remove the implicit flush from the set_cr3 handlers, so that the
> callers are able to decide whether to flush the TLB or not.
>
> Signed-off-by: Junaid Shahid <junaids@xxxxxxxxxx>
> ---
> arch/x86/kvm/mmu.c | 2 ++
> arch/x86/kvm/mmu.h | 1 -
> arch/x86/kvm/svm.c | 4 ----
> arch/x86/kvm/vmx.c | 1 -
> 4 files changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
> index 94d4cf4cb743..41c5440067f2 100644
> --- a/arch/x86/kvm/mmu.c
> +++ b/arch/x86/kvm/mmu.c
> @@ -4059,6 +4059,7 @@ static bool fast_cr3_switch(struct kvm_vcpu *vcpu, gpa_t new_cr3,
>
> kvm_make_request(KVM_REQ_LOAD_CR3, vcpu);
> kvm_make_request(KVM_REQ_MMU_SYNC, vcpu);
> + kvm_x86_ops->tlb_flush(vcpu, true);
Shouldn't this be "kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu)" instead
of an immediate TLB flush since we're delaying the load and sync until
vcpu_enter_guest()?
> __clear_sp_write_flooding_count(
> page_header(mmu->root_hpa));
>
> @@ -4841,6 +4842,7 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu)
> if (r)
> goto out;
> kvm_mmu_load_cr3(vcpu);
> + kvm_x86_ops->tlb_flush(vcpu, true);
> out:
> return r;
> }
> diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
> index e8e439c19a74..9950c04e1239 100644
> --- a/arch/x86/kvm/mmu.h
> +++ b/arch/x86/kvm/mmu.h
> @@ -99,7 +99,6 @@ static inline int kvm_mmu_reload(struct kvm_vcpu *vcpu)
>
> static inline void kvm_mmu_load_cr3(struct kvm_vcpu *vcpu)
> {
> - /* set_cr3() should ensure TLB has been flushed */
> if (VALID_PAGE(vcpu->arch.mmu.root_hpa))
> vcpu->arch.mmu.set_cr3(vcpu, vcpu->arch.mmu.root_hpa);
> }
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index d9305f1723f5..9f12f67564ef 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -2875,7 +2875,6 @@ static void nested_svm_set_tdp_cr3(struct kvm_vcpu *vcpu,
>
> svm->vmcb->control.nested_cr3 = __sme_set(root);
> mark_dirty(svm->vmcb, VMCB_NPT);
> - svm_flush_tlb(vcpu, true);
> }
>
> static void nested_svm_inject_npf_exit(struct kvm_vcpu *vcpu,
> @@ -5740,7 +5739,6 @@ static void svm_set_cr3(struct kvm_vcpu *vcpu, unsigned long root)
>
> svm->vmcb->save.cr3 = __sme_set(root);
> mark_dirty(svm->vmcb, VMCB_CR);
> - svm_flush_tlb(vcpu, true);
> }
>
> static void set_tdp_cr3(struct kvm_vcpu *vcpu, unsigned long root)
> @@ -5753,8 +5751,6 @@ static void set_tdp_cr3(struct kvm_vcpu *vcpu, unsigned long root)
> /* Also sync guest cr3 here in case we live migrate */
> svm->vmcb->save.cr3 = kvm_read_cr3(vcpu);
> mark_dirty(svm->vmcb, VMCB_CR);
> -
> - svm_flush_tlb(vcpu, true);
> }
>
> static int is_disabled(void)
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index 9c85c6249280..90898442172c 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -4966,7 +4966,6 @@ static void vmx_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
> ept_load_pdptrs(vcpu);
> }
>
> - vmx_flush_tlb(vcpu, true);
> vmcs_writel(GUEST_CR3, guest_cr3);
> }
>
> --
> 2.18.0.rc1.242.g61856ae69a-goog
>
