On 29/04/2015 15:05, Jan Kiszka wrote: > > Yeah... I hear you. Ok, let me put it this way - Assume that we can > > defer this allocation up until the point that the nested subsystem is > > actually used i.e L1 tries running a guest and we try to allocate this > > area. If get_free_page() failed in that case, would we still want to > > kill L1 too ? I guess no. > > We could block the hypervisor thread on the allocation, just like it > would block on faults for swapped out pages or new ones that have to be > reclaimed from the page cache first. In that case we should avoid making the allocation GFP_ATOMIC to begin with. If a GFP_KERNEL allocation failed, returning -ENOMEM from KVM_RUN (which practically means killing the guest) would actually be a very real possibility. 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