----- junaids@xxxxxxxxxx wrote:
> kvm_mmu_invlpg() and kvm_mmu_invpcid_gva() only need to flush the TLB
> entries for the specific guest virtual address, instead of flushing
> all
> TLB entries associated with the VM.
>
> Signed-off-by: Junaid Shahid <junaids@xxxxxxxxxx>
> ---
> arch/x86/include/asm/kvm_host.h | 6 ++++++
> arch/x86/kvm/mmu.c | 6 +++---
> arch/x86/kvm/svm.c | 8 ++++++++
> arch/x86/kvm/vmx.c | 24 ++++++++++++++++++++++++
> 4 files changed, 41 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/include/asm/kvm_host.h
> b/arch/x86/include/asm/kvm_host.h
> index 7b93ea4e16f3..55aaf12c13ea 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -976,6 +976,12 @@ struct kvm_x86_ops {
>
> void (*tlb_flush)(struct kvm_vcpu *vcpu, bool invalidate_gpa);
>
> + /*
> + * Flush any TLB entries associated with the given GVA.
> + * Does not need to flush GPA->HPA mappings.
> + */
> + void (*tlb_flush_gva)(struct kvm_vcpu *vcpu, gva_t addr);
> +
> void (*run)(struct kvm_vcpu *vcpu);
> int (*handle_exit)(struct kvm_vcpu *vcpu);
> void (*skip_emulated_instruction)(struct kvm_vcpu *vcpu);
> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
> index 160dc84c15be..7cfc30409517 100644
> --- a/arch/x86/kvm/mmu.c
> +++ b/arch/x86/kvm/mmu.c
> @@ -5166,7 +5166,7 @@ void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t
> gva)
> if (VALID_PAGE(mmu->prev_root_hpa))
> mmu->invlpg(vcpu, gva, mmu->prev_root_hpa);
>
> - kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
> + kvm_x86_ops->tlb_flush_gva(vcpu, gva);
> ++vcpu->stat.invlpg;
> }
> EXPORT_SYMBOL_GPL(kvm_mmu_invlpg);
> @@ -5177,13 +5177,13 @@ void kvm_mmu_invpcid_gva(struct kvm_vcpu
> *vcpu, gva_t gva, unsigned long pcid)
>
> if (pcid == kvm_get_active_pcid(vcpu)) {
> mmu->invlpg(vcpu, gva, mmu->root_hpa);
> - kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
> + kvm_x86_ops->tlb_flush_gva(vcpu, gva);
> }
>
> if (VALID_PAGE(mmu->prev_root_hpa) &&
> pcid == kvm_get_pcid(vcpu, mmu->prev_cr3)) {
> mmu->invlpg(vcpu, gva, mmu->prev_root_hpa);
> - kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
> + kvm_x86_ops->tlb_flush_gva(vcpu, gva);
> }
>
> ++vcpu->stat.invlpg;
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index fd8b0dc5136f..ffc92aa2ebf5 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -5401,6 +5401,13 @@ static void svm_flush_tlb(struct kvm_vcpu
> *vcpu, bool invalidate_gpa)
> svm->asid_generation--;
> }
>
> +static void svm_flush_tlb_gva(struct kvm_vcpu *vcpu, gva_t gva)
> +{
> + struct vcpu_svm *svm = to_svm(vcpu);
> +
> + invlpga(gva, svm->vmcb->control.asid);
> +}
> +
> static void svm_prepare_guest_switch(struct kvm_vcpu *vcpu)
> {
> }
> @@ -7059,6 +7066,7 @@ static struct kvm_x86_ops svm_x86_ops
> __ro_after_init = {
> .set_rflags = svm_set_rflags,
>
> .tlb_flush = svm_flush_tlb,
> + .tlb_flush_gva = svm_flush_tlb_gva,
>
> .run = svm_vcpu_run,
> .handle_exit = handle_exit,
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index b11ec063564f..45bee828bc97 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -1393,6 +1393,11 @@ static inline bool
> cpu_has_vmx_invept_global(void)
> return vmx_capability.ept & VMX_EPT_EXTENT_GLOBAL_BIT;
> }
>
> +static inline bool cpu_has_vmx_invvpid_addr(void)
> +{
> + return vmx_capability.vpid & VMX_VPID_EXTENT_INDIVIDUAL_ADDR_BIT;
> +}
> +
> static inline bool cpu_has_vmx_invvpid_single(void)
> {
> return vmx_capability.vpid & VMX_VPID_EXTENT_SINGLE_CONTEXT_BIT;
> @@ -1754,6 +1759,16 @@ static void loaded_vmcs_clear(struct
> loaded_vmcs *loaded_vmcs)
> __loaded_vmcs_clear, loaded_vmcs, 1);
> }
>
> +static inline bool vpid_sync_vcpu_addr(int vpid, gva_t addr)
> +{
> + if (cpu_has_vmx_invvpid_addr()) {
> + __invvpid(VMX_VPID_EXTENT_INDIVIDUAL_ADDR, vpid, addr);
> + return true;
> + }
> +
> + return false;
> +}
> +
> static inline void vpid_sync_vcpu_single(int vpid)
> {
> if (vpid == 0)
> @@ -4553,6 +4568,14 @@ static void vmx_flush_tlb(struct kvm_vcpu
> *vcpu, bool invalidate_gpa)
> __vmx_flush_tlb(vcpu, to_vmx(vcpu)->vpid, invalidate_gpa);
> }
>
> +static void vmx_flush_tlb_gva(struct kvm_vcpu *vcpu, gva_t addr)
> +{
> + int vpid = to_vmx(vcpu)->vpid;
> +
> + if (!vpid_sync_vcpu_addr(vpid, addr))
> + vpid_sync_context(vpid);
> +}
If VPID is not supported or module parameter enable_vpid=0, then vmx_flush_tlb_gva() will do nothing.
I think that if !enable_vpid you should invlpg addr.
> +
> static void vmx_flush_tlb_ept_only(struct kvm_vcpu *vcpu)
> {
> if (enable_ept)
> @@ -12765,6 +12788,7 @@ static struct kvm_x86_ops vmx_x86_ops
> __ro_after_init = {
> .set_rflags = vmx_set_rflags,
>
> .tlb_flush = vmx_flush_tlb,
> + .tlb_flush_gva = vmx_flush_tlb_gva,
>
> .run = vmx_vcpu_run,
> .handle_exit = vmx_handle_exit,
> --
> 2.17.0.441.gb46fe60e1d-goog
