KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS
if (unlikely(gen & KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS))
WARN_ON_ONCE(gen & KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS);
if (unlikely(gen & KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS))
WARN_ON(gen & KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS);
slots->generation = gen | KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS;
gen = slots->generation & ~KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS;