On 16/10/19 19:42, Sean Christopherson wrote: > KVM uses a locked cmpxchg in emulator_cmpxchg_emulated() and the address > is guest controlled, e.g. a guest could coerce the host into disabling > split-lock detection via the host's #AC handler by triggering emulation > and inducing an #AC in the emulator. Yes, that's a possible issue. Paolo