diff options
| author | Sean Christopherson <sean.j.christopherson@intel.com> | 2020-02-07 20:37:41 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-02-19 21:53:04 +0300 |
| commit | db6f68908bce8eb523297e663b92a9bc913e6915 (patch) | |
| tree | c3d9064d25f954cc33193032189fc2d43c484e23 /arch/x86/kvm/vmx/vmx.c | |
| parent | ce8b9b8032bddadb1ed8fcf946ba6482f4938c51 (diff) | |
| download | linux-db6f68908bce8eb523297e663b92a9bc913e6915.tar.xz | |
KVM: nVMX: Use correct root level for nested EPT shadow page tables
commit 148d735eb55d32848c3379e460ce365f2c1cbe4b upstream.
Hardcode the EPT page-walk level for L2 to be 4 levels, as KVM's MMU
currently also hardcodes the page walk level for nested EPT to be 4
levels. The L2 guest is all but guaranteed to soft hang on its first
instruction when L1 is using EPT, as KVM will construct 4-level page
tables and then tell hardware to use 5-level page tables.
Fixes: 855feb673640 ("KVM: MMU: Add 5 level EPT & Shadow page table support.")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/kvm/vmx/vmx.c')
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index dc7c166c4335..84b57b461ad6 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2975,6 +2975,9 @@ void vmx_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) static int get_ept_level(struct kvm_vcpu *vcpu) { + /* Nested EPT currently only supports 4-level walks. */ + if (is_guest_mode(vcpu) && nested_cpu_has_ept(get_vmcs12(vcpu))) + return 4; if (cpu_has_vmx_ept_5levels() && (cpuid_maxphyaddr(vcpu) > 48)) return 5; return 4; |