From 9ec38fcb983c4c11b7b2cebbc6dc4361ffdc58e2 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Wed, 5 May 2010 16:04:45 +0200 Subject: KVM: SVM: Don't allow nested guest to VMMCALL into host This patch disables the possibility for a l2-guest to do a VMMCALL directly into the host. This would happen if the l1-hypervisor doesn't intercept VMMCALL and the l2-guest executes this instruction. Signed-off-by: Joerg Roedel Signed-off-by: Avi Kivity Signed-off-by: Greg Kroah-Hartman (cherry picked from commit 0d945bd9351199744c1e89d57a70615b6ee9f394) --- arch/x86/kvm/svm.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'arch/x86/kvm/svm.c') diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 9b99342d75f..a2f839cbad0 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1829,8 +1829,13 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm) svm->vmcb->control.intercept_cr_write &= ~INTERCEPT_CR8_MASK; } - /* We don't want a nested guest to be more powerful than the guest, - so all intercepts are ORed */ + /* We don't want to see VMMCALLs from a nested guest */ + svm->vmcb->control.intercept &= ~(1ULL << INTERCEPT_VMMCALL); + + /* + * We don't want a nested guest to be more powerful than the guest, so + * all intercepts are ORed + */ svm->vmcb->control.intercept_cr_read |= nested_vmcb->control.intercept_cr_read; svm->vmcb->control.intercept_cr_write |= -- cgit