diff options
author | Liran Alon <liran.alon@oracle.com> | 2018-10-08 23:42:17 +0300 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2018-10-13 12:00:53 +0200 |
commit | 1438921c6dc1bbdce800bfc7db04bd15cb260fc0 (patch) | |
tree | 946aa91da25432305550deeb279c02c6e8e99703 /arch/x86/kvm/vmx.c | |
parent | 3de6347bf96abead5c5257b43a58ca0a057df894 (diff) |
KVM: nVMX: Flush TLB entries tagged by dest EPTP on L1<->L2 transitions
If L1 and L2 share VPID (because L1 don't use VPID or we haven't allocated
a vpid02), we need to flush TLB on L1<->L2 transitions.
Before this patch, this TLB flushing was done by vmx_flush_tlb().
If L0 use EPT, this will translate into INVEPT(active_eptp);
However, if L1 use EPT, in L1->L2 VMEntry, active EPTP is EPTP01 but
TLB entries populated by L2 are tagged with EPTP02.
Therefore we should delay vmx_flush_tlb() until active_eptp is EPTP02.
To achieve this, instead of directly calling vmx_flush_tlb() we request
it to be called by KVM_REQ_TLB_FLUSH which is evaluated after
KVM_REQ_LOAD_CR3 which sets the active_eptp to EPTP02 as required.
Similarly, on L2->L1 VMExit, active EPTP is EPTP02 but TLB entries
populated by L1 are tagged with EPTP01 and therefore we should delay
vmx_flush_tlb() until active_eptp is EPTP01.
Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/vmx.c')
-rw-r--r-- | arch/x86/kvm/vmx.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 022642da8c5c..a4fa15b8b1ae 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -12290,7 +12290,15 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12, __vmx_flush_tlb(vcpu, vmx->nested.vpid02, true); } } else { - vmx_flush_tlb(vcpu, true); + /* + * If L1 use EPT, then L0 needs to execute INVEPT on + * EPTP02 instead of EPTP01. Therefore, delay TLB + * flush until vmcs02->eptp is fully updated by + * KVM_REQ_LOAD_CR3. Note that this assumes + * KVM_REQ_TLB_FLUSH is evaluated after + * KVM_REQ_LOAD_CR3 in vcpu_enter_guest(). + */ + kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu); } } @@ -13188,10 +13196,14 @@ static void load_vmcs12_host_state(struct kvm_vcpu *vcpu, * Therefore, flush TLB only in case vmcs01 uses VPID and * vmcs12 don't use VPID as in this case L1 & L2 TLB entries * are both tagged with vmx->vpid. + * + * If vmcs12 uses EPT, we need to execute this flush on EPTP01 + * and therefore we request the TLB flush to happen only after VMCS EPTP + * has been set by KVM_REQ_LOAD_CR3. */ if (enable_vpid && !(nested_cpu_has_vpid(vmcs12) && to_vmx(vcpu)->nested.vpid02)) { - vmx_flush_tlb(vcpu, true); + kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu); } vmcs_write32(GUEST_SYSENTER_CS, vmcs12->host_ia32_sysenter_cs); |