diff options
| author | Jan Kiszka <jan.kiszka@web.de> | 2013-12-28 16:31:52 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-01-09 12:25:12 -0800 |
| commit | 366aaa038f472c47493fb6502f58377363d100bc (patch) | |
| tree | fef9d3cfc4830d1c74ef8986588eed4b91d55ce4 /arch | |
| parent | d10d0a2337097fa907f22af6ad0ae0dc0ff39fbf (diff) | |
KVM: nVMX: Unconditionally uninit the MMU on nested vmexit
commit 29bf08f12b2fd72b882da0d85b7385e4a438a297 upstream.
Three reasons for doing this: 1. arch.walk_mmu points to arch.mmu anyway
in case nested EPT wasn't in use. 2. this aligns VMX with SVM. But 3. is
most important: nested_cpu_has_ept(vmcs12) queries the VMCS page, and if
one guest VCPU manipulates the page of another VCPU in L2, we may be
fooled to skip over the nested_ept_uninit_mmu_context, leaving mmu in
nested state. That can crash the host later on if nested_ept_get_cr3 is
invoked while L1 already left vmxon and nested.current_vmcs12 became
NULL therefore.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/vmx.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 2b2fce1b2009..6128914ee873 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -8218,8 +8218,7 @@ static void load_vmcs12_host_state(struct kvm_vcpu *vcpu, vcpu->arch.cr4_guest_owned_bits = ~vmcs_readl(CR4_GUEST_HOST_MASK); kvm_set_cr4(vcpu, vmcs12->host_cr4); - if (nested_cpu_has_ept(vmcs12)) - nested_ept_uninit_mmu_context(vcpu); + nested_ept_uninit_mmu_context(vcpu); kvm_set_cr3(vcpu, vmcs12->host_cr3); kvm_mmu_reset_context(vcpu); |