[198/200] KVM: SVM: Dont allow nested guest to VMMCALL into host
diff mbox series

Message ID 20100701174303.227322053@clark.site
State New, archived
Headers show
  • stable review
Related show

Commit Message

Greg KH July 1, 2010, 5:44 p.m. UTC
2.6.34-stable review patch.  If anyone has any objections, please let me know.


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 |    3 +++
 1 file changed, 3 insertions(+)

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

diff mbox series

--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1854,6 +1854,9 @@  static bool nested_svm_vmrun(struct vcpu
 		svm->vmcb->control.intercept_cr_write &= ~INTERCEPT_CR8_MASK;
+	/* 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 |=