On 11/11/2015 13:47, Austin S Hemmelgarn wrote: >> > I just finished running a couple of tests in a KVM instance running > nested on a Xen HVM instance, and found no issues, so for the set as a > whole: > > Tested-by: Austin S. Hemmelgarn <ahferroin7@xxxxxxxxx> > > Now to hope the equivalent fix for Xen gets into the Gentoo repositories > soon, as the issue propagates down through nested virtualization and > ties up the CPU regardless (and in turn triggers the watchdog). Note that nested guests should _not_ lock up the outer (L0) hypervisor if the outer hypervisor has the fix. At least this is the case for KVM: a fixed outer KVM can protect any vulnerable nested (L1) hypervisor from malicious nested guests. A vulnerable outer KVM is also protected if the nested hypervisor has the workaround. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html