Messages in this thread Patch in this message | | | Date | Thu, 01 Jul 2010 10:35:45 -0700 | From | Greg KH <> | Subject | [patch 159/164] KVM: SVM: Dont allow nested guest to VMMCALL into host |
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2.6.33-stable review patch. If anyone has any objections, please let me know.
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From: Joerg Roedel <joerg.roedel@amd.com>
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 <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> (cherry picked from commit 0d945bd9351199744c1e89d57a70615b6ee9f394) --- arch/x86/kvm/svm.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
--- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1829,8 +1829,13 @@ static bool nested_svm_vmrun(struct vcpu 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 |=
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