diff options
| author | Nadav Har'El <nyh@il.ibm.com> | 2011-05-25 23:03:24 +0300 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2011-07-12 11:45:10 +0300 |
| commit | 5e1746d6205d1efa3193cc0c67aa2d15e54799bd (patch) | |
| tree | 9234ab8fddb5e7a8d86b506a19d7697566d51cfb /arch/x86/kvm/svm.c | |
| parent | ec378aeef9dfc7c4ba72e9bd6cd4bd6f7d5fd0cc (diff) | |
KVM: nVMX: Allow setting the VMXE bit in CR4
This patch allows the guest to enable the VMXE bit in CR4, which is a
prerequisite to running VMXON.
Whether to allow setting the VMXE bit now depends on the architecture (svm
or vmx), so its checking has moved to kvm_x86_ops->set_cr4(). This function
now returns an int: If kvm_x86_ops->set_cr4() returns 1, __kvm_set_cr4()
will also return 1, and this will cause kvm_set_cr4() will throw a #GP.
Turning on the VMXE bit is allowed only when the nested VMX feature is
enabled, and turning it off is forbidden after a vmxon.
Signed-off-by: Nadav Har'El <nyh@il.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'arch/x86/kvm/svm.c')
| -rw-r--r-- | arch/x86/kvm/svm.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 506e4fe23ad..475d1c94850 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1496,11 +1496,14 @@ static void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) update_cr0_intercept(svm); } -static void svm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) +static int svm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) { unsigned long host_cr4_mce = read_cr4() & X86_CR4_MCE; unsigned long old_cr4 = to_svm(vcpu)->vmcb->save.cr4; + if (cr4 & X86_CR4_VMXE) + return 1; + if (npt_enabled && ((old_cr4 ^ cr4) & X86_CR4_PGE)) svm_flush_tlb(vcpu); @@ -1510,6 +1513,7 @@ static void svm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) cr4 |= host_cr4_mce; to_svm(vcpu)->vmcb->save.cr4 = cr4; mark_dirty(to_svm(vcpu)->vmcb, VMCB_CR); + return 0; } static void svm_set_segment(struct kvm_vcpu *vcpu, |