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| author | Paolo Bonzini <pbonzini@redhat.com> | 2020-07-10 17:48:10 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-07-10 17:01:52 -0400 |
| commit | 8c4182bd27cafc2b0f94564485c89ed366c1572c (patch) | |
| tree | 4a1175a70e143b14d4c47a8ab90dd1cb1a8a3c78 /arch/x86/kvm/vmx/vmx.c | |
| parent | 1dbf5d68af6ffdb1c8b0d38ee565768e22e2c3ab (diff) | |
KVM: VMX: optimize #PF injection when MAXPHYADDR does not match
Ignore non-present page faults, since those cannot have reserved
bits set.
When running access.flat with "-cpu Haswell,phys-bits=36", the
number of trapped page faults goes down from 8872644 to 3978948.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200710154811.418214-9-mgamal@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/vmx/vmx.c')
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 5518f75c9b19..962a78c7dde5 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -4355,6 +4355,16 @@ static void init_vmcs(struct vcpu_vmx *vmx) vmx->pt_desc.guest.output_mask = 0x7F; vmcs_write64(GUEST_IA32_RTIT_CTL, 0); } + + /* + * If EPT is enabled, #PF is only trapped if MAXPHYADDR is mismatched + * between guest and host. In that case we only care about present + * faults. + */ + if (enable_ept) { + vmcs_write32(PAGE_FAULT_ERROR_CODE_MASK, PFERR_PRESENT_MASK); + vmcs_write32(PAGE_FAULT_ERROR_CODE_MATCH, PFERR_PRESENT_MASK); + } } static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) |