I have a virtual infrastructure and openstack installed in it, the libvirt_type=qemu works fine, but when I change the libvirt_type=kvm the instances spawn up but no log is generated and I can't see the display in vnc. My compute nodes support kvm as determined from the command grep -E 'svm|vmx' /proc/cpuinfo the output is as follows:

flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl tsc_reliable nonstop_tsc aperfmperf pni pclmulqdq ssse3 cx16 sse4_1 sse4_2 x2apic popcnt aes xsave avx hypervisor lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw xop fma4 arat npt svm_lock nrip_save vmcb_clean flushbyasid decodeassists

What may be the issue?