The basic idea is to let userspace provide the desired maximal number of VCPUs and allocate only necessary memory for them. The goal is to freeze KVM_MAX_VCPUS at its current level and only increase the new KVM_MAX_CONFIGURABLE_VCPUS, probably directly to INT_MAX/KVM_VCPU_ID, so we don't have to worry about it for a while. PPC should be interested in this as they set KVM_MAX_VCPUS to NR_CPUS and probably waste few pages for every guest this way. Radim Krčmář (4): KVM: remove unused __KVM_HAVE_ARCH_VM_ALLOC KVM: allocate kvm->vcpus separately KVM: add KVM_CREATE_VM2 system ioctl KVM: x86: enable configurable MAX_VCPU Documentation/virtual/kvm/api.txt | 28 +++++++++++++++ arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/irq_comm.c | 4 +-- include/linux/kvm_host.h | 23 +++++------- include/uapi/linux/kvm.h | 8 +++++ virt/kvm/kvm_main.c | 76 +++++++++++++++++++++++++++++++++------ 6 files changed, 114 insertions(+), 26 deletions(-) -- 2.12.0
